Softride Frankenstem (MTB)
Peter Norquist
suspension system. From a pure "spec" vantage point, it appears superior to shocked forks in weight, price,
length of travel and maintenance.
Any opinions, facts or fantasies out there?
Thanks.
-Peter
Jim Collias
writes:
You just said it all.... It is indeed far superior to suspension forks with
independent slider-type legs. The AMP fork is the only one that I've tried
that's in Allsop's ballpark as far as simplicity, maintenance, and handling,
but the Allsop is still the winner in price, travel, and weight.
- Jim
Keith Erskine
> In article <2511v0$8...@lll-winken.llnl.gov>, norq...@llnl.gov (Peter Norquist)
> writes:
> You just said it all.... It is indeed far superior to suspension forks with
> independent slider-type legs. The AMP fork is the only one that I've tried
> that's in Allsop's ballpark as far as simplicity, maintenance, and handling,
> but the Allsop is still the winner in price, travel, and weight.
The Allsop is NOT far superior to suspension forks.
I have 2 Allsops & 1 RockShox Mag20.
The Allsop bobs horribly when sprinting out of the saddle. You cannot
use your upper body at all for power generation with the Allsop. A
Mag20 is much less annoying when pulling hard on the bars.
The Allsop does not provide benefit for the riders crotch and feet.
A shock fork provides suspension for the whole bike, not just the
riders hands.
Shock theory says "minimize unsprung weight". Obviously, the shock fork
is much closer to this ideal than a shock stem. The weight of the whole
bike & riders body helps smooth the ride on a shock fork bike, whereas
the riders hands do all of the work to smooth out the ride on a shock stem.
The front wheel tracks the ground better with a shock fork.
Keith Erskine
Gary W. Mahan
>> but the Allsop is still the winner in price, travel, and weight.
>The Allsop is NOT far superior to suspension forks.
Well, I am glad somebody finally said this!
>I have 2 Allsops & 1 RockShox Mag20.
>The Allsop bobs horribly when sprinting out of the saddle. You cannot
>use your upper body at all for power generation with the Allsop. A
>Mag20 is much less annoying when pulling hard on the bars.
>The Allsop does not provide benefit for the riders crotch and feet.
>A shock fork provides suspension for the whole bike, not just the
>riders hands.
>Shock theory says "minimize unsprung weight". Obviously, the shock fork
>is much closer to this ideal than a shock stem. The weight of the whole
>bike & riders body helps smooth the ride on a shock fork bike, whereas
>the riders hands do all of the work to smooth out the ride on a shock stem.
Very important concept, Imagine a car with a rigid suspension but a
suspended seat!
>The front wheel tracks the ground better with a shock fork.
Most definately!
There has been lots of talk about how Suspension stems are cheaper and weigh less.
Note: prices and specs are to the best of my memory from the latest performance catalog.
Suspension Stem
Price $~260 (Allsop Aluminum I think)
Weight ~500-600 grams (replaces stem of ~300 grams)
Net Weight gain = ~200-300 grams
Geometry Change: None
Suspension Fork
Price $~260 (Rox Shock Quadra)
Weight ~1460 grams (replaces Fork of ~1138 lbs (on my bike))
Net Weight Gain = ~322 grams
Geometry Change: Minimal(Really!)
Looks pretty close to me! So how is a supension stem so superior!
Mark Obsniuk
My RockShox Mag20s are doing fine with over 16months of hard use. Several oil
changes (just use Dextron ATF the other stuff is just crap and costs more) It
is easier to maintain then most forks. That comes from people who actually care
about there Manitou forks. An oil change takes less then 10 minutes from start
to finish. Do it at night pump em up and you are ready to go in the morning.
My stem weighs 180grams and it is not a clamp on. So that would be a lot of
weight gain for me to switch to the Frankenstem. My Rockshox perform so much
better then my friends Manitous. I am in very good control while he is getting
bounced around from the lack of dampining. And from what I here the new Mag 21
is both bullet proof and supple in most conditions.
Rockshoxs forever.
Mark
David Mackintosh
>Weight ~1460 grams (replaces Fork of ~1138 lbs (on my bike))
Man, that's one heavy fork!
Gary W. Mahan
Yes, it is very hard on the uphills, but I really fly on the downhills.
Handling is a little slow though.
Seriously, I meant 1138 grams.
Rick Brusuelas
> >use your upper body at all for power generation with the Allsop. A
> >Mag20 is much less annoying when pulling hard on the bars.
Funny, I have had my Allsop for over six months now, and I don't
"bob" at all when I climb, nor when I "stand and hammer" on
flats. Seems to me that the frame, fork, and wheel stay quite
rigid, which is definitely NOT true with a fork suspension. The
stem stays at the top position. Do forks even have a "top position"?
> >Shock theory says "minimize unsprung weight". Obviously, the shock fork
> >is much closer to this ideal than a shock stem. The weight of the whole
> >bike & riders body helps smooth the ride on a shock fork bike, whereas
> >the riders hands do all of the work to smooth out the ride on a shock stem.
> Very important concept, Imagine a car with a rigid suspension but a
> suspended seat!
Yikes, this argument (as well as the motorycle argument) just does
not apply with a bicycle, where the rider's weight is far greater than
the vehicle (in this case, a bike).
> >The front wheel tracks the ground better with a shock fork.
> Most definately!
Bzzzzzt! Wrong answer again. The wheel hits a bump (log, rock, rut,
whatever) and moves upwards, whether with a fork or a stem. The
Allsop's 2-3" travel is unhindered by fork tube stiction or
lockout threshold, so an argument could be made that it handles
and tracks better than a fork.
> There has been lots of talk about how Suspension stems are cheaper and weigh less.
Here's the weight and price differences in my experience (a 92 18" MB-3)
Rock Shock Mag 21* Allsop
fork 3.3 lbs 1.6 lbs (Ritchey Logic)
Stem 350 grams (Ritchey Force) 580 grams
Price: $389 (as low as $299 mail order) $250.
* RS Quadra price $260. Weight is 3.2 pounds. Never considered
the Quadra when I bought the Allsop.
Now converting to grams (1 lb av = 453 grams). Thus, the Rock
Shox equipped version of my bike would be 1495+350=1845 grams.
The Allsop verion of my bike would be 725+580=1305 grams.
The difference in weight is 1845-1305=540 grams or 1.2 pounds.
^^^^^^^^^^^
And the one (1) degree geometry change caused by the RS's added
length is significant in low speed steering. And this does not
even discuss the reliability and maintenance benefits of the
Allsop over air/oil or even elastomer shocks.
This is not to say that the Allsop is for everyone. But to dismiss
it as a suspension alternative is a mistake. Team Ritchey uses it
successfully. Leonard Zinn and Scot Nicol (Ibis) reviewed it
very favorably in Velo News. And Joe Murray (Kona) uses it on his
own bike over even his own suspension fork design (the Z-Link).
Rick Brusuelas
Sun Library
Gary W. Mahan
>Yikes, this argument (as well as the motorycle argument) just does
>not apply with a bicycle, where the rider's weight is far greater than
>the vehicle (in this case, a bike).
Unsprung weight will always be a factor and will always apply.
Maybe not as much as on a motorcycle but it is still important.
>Bzzzzzt! Wrong answer again. The wheel hits a bump (log, rock, rut,
>whatever) and moves upwards, whether with a fork or a stem. The
>Allsop's 2-3" travel is unhindered by fork tube stiction or
>lockout threshold, so an argument could be made that it handles
>and tracks better than a fork.
Bzzt!, Bzzt!, Bzzt!
With the stem, the bike and wheel will move upwards, with the
susp. fork the wheel will move more than the bike (depending
on stiffness). Sure stiction will lessen some of the advantage
but there still will be an advantage with the susp. fork.
One disadvantage of the susp fork would definately be the brake flex.
Not a major problem, but noticable nontheless.
>Here's the weight and price differences in my experience (a 92 18" MB-3)
> Rock Shock Mag 21* Allsop
>fork 3.3 lbs 1.6 lbs (Ritchey Logic)
>Stem 350 grams (Ritchey Force) 580 grams
>Price: $389 (as low as $299 mail order) $250.
> * RS Quadra price $260. Weight is 3.2 pounds. Never considered
> the Quadra when I bought the Allsop.
Well, it looks like you came out better(as far as weight). For my case, there
was no considerable weight difference. And I got the RS quadra for $219.
I think the difference between your case and mine was the weight of the fork (2.5# vs 1.6#). If I had your bike I probably would have chosen the allsop if weight was a major concern.
>And the one (1) degree geometry change caused by the RS's added
>length is significant in low speed steering. And this does not
>even discuss the reliability and maintenance benefits of the
>Allsop over air/oil or even elastomer shocks.
The geometry change will vary from bike to bike. The handling
difference will also vary. It all depends on the original fork!
BTW, who goes slow (not me). Seriously, I cannot notice any significant!!!
difference in slow speed handling. I just have to adjust (if needed)
Well I can let you know on the reliability of the quadra's in a few years.
As far as maintenance (what maintenance!)
>This is not to say that the Allsop is for everyone. But to dismiss
>it as a suspension alternative is a mistake. Team Ritchey uses it
>successfully. Leonard Zinn and Scot Nicol (Ibis) reviewed it
>very favorably in Velo News. And Joe Murray (Kona) uses it on his
>own bike over even his own suspension fork design (the Z-Link).
To also classify it as superior to susp. forks is also a mistake.
This is what I was originaly responding to. Both have their pros and cons
Look at all the people who uses susp. forks (too many to list)
BTW, quadras get good reviews also. I just had to throw that one in!
Jim Collias
|> Very important concept, Imagine a car with a rigid suspension but a
|> suspended seat!
That comment makes no sense. A car can weigh almost 10 times more than the
weight of it's occupant, while the opposite holds true with bicycles. It makes
more sense to suspend only the rider when the weight of the bike is only about
1/8 the total weight of the system.
|> >The front wheel tracks the ground better with a shock fork.
Really? Then why are there such aftermarket products as Monster Fork Braces and
SupperBubba Front Hubs? It's to make up for the slop introduced by the
independent fork legs. A ridgid fork will ALWAYS be more accurate than a
suspension fork. How you choose to absorb the bumps is up to you.
And when it comes to replacing a high-performance rigid fork of 700 grams with a
suspension fork, geometry isn't the only aspect that will be tweeked.
- Jim
ps. An aluminum Allsop stem can be had for about $190 if you do your homework.
Jim Collias
|> The stem is a bad idea. As far as I know it sucks.
And if MBA told you to jump off a bridge, would you?
Bill Broadley
change the frame geometry.
But as far as weight reduction keep in mind that you need to compare
frankenstem vs stem weight for the weight penalty, vs suspension fork
vs fork wieght penalty.
Not suspension stem vs suspension fork, which is a misleading figure.
I found that if your in the high end that in each case you lose approximately
the same amount of weight.
In general the stem seems more oriented towards rider comfort, the
fork more for performance.
The fork suspends the bike not just the handlebars, and most of the weight
of a rider is typically on the seat/pedals. Granted that neither moves
as much relative to the handlebars given the same size bump.
--
Bill 1st> Broa...@neurocog.lrdc.pitt.edu
Broa...@schneider3.lrdc.pitt.edu <2nd 3rd> Broa...@pitt.edu
Linux is great. Bike to live, live to bike. PGP-ok
bui tho xuan
As I understood it, the principle problem with stem suspensions is
that they change the rider's geometry when activated, i.e., as the
stem drops, the rider must pivot at the hip. Supposedly, this interfere
with a smooth cadence. This makes sense to me, but since I've never
used one, I'd like to get more input.
tho
Rick Brusuelas
> With the stem, the bike and wheel will move upwards, with the
> susp. fork the wheel will move more than the bike (depending
> on stiffness). Sure stiction will lessen some of the advantage
> but there still will be an advantage with the susp. fork.
*LOUD BZZZZZZZT* (boy this is fun;-)
Your conclusion would be tough to prove. Bicycling Magazine
(and now Mountain Bike) attempts to measure suspension
effectiveness with a device they call MONSTER which measures
handlebar and fork movement in Gs over time over a
2" bump. Their analysis showed the Allsop worked quite well,
better than many suspension forks (although I can't say I
have seen the review/graph on the Quadra).
I would also submit that the best bike for climbing is the lighter
bike. My MB-3 started out fairly heavy, so I definitely
wanted to avoid adding more weight on the bike.
I guess you have to "weigh" (Allop is lighter ;-) the travel
(amount and smoothness) of the Allsop versus the stiction and
flex of the suspension fork. I preferred the feel of the Allsop.
> One disadvantage of the susp fork would definately be the brake flex.
> Not a major problem, but noticable nontheless.
Heck, my rigid Ritchey fork suffers from brake flex... a sliding
tube fork must exhibit greater flex (if not, why do many people
add weight and expense with a brake booster up top and a suspension hub
below?).
> The geometry change will vary from bike to bike. The handling
> difference will also vary. It all depends on the original fork!
> BTW, who goes slow (not me). Seriously, I cannot notice any significant!!!
> difference in slow speed handling. I just have to adjust (if needed)
>
> Well I can let you know on the reliability of the quadra's in a few years.
> As far as maintenance (what maintenance!)
All sliding tube suspension forks (will) require some degree of
maintenance. I know two people with Manitous who had to dissassemble
when they "froze". Even elastomer forks have seals that may fail.
I tend to like to ride through creeks, so this was a factor in my
decision.
> To also classify it as superior to susp. forks is also a mistake.
> This is what I was originaly responding to. Both have their pros and cons
Agreed. I tell people that *I* prefer the Allsop to any of the air/oil
or elastomer-based forks that I have tried so far (this list includes
RS Mag21, Mag20, Quadra, Manitou, Scott, ProForx, and Trek). I have
tried the AMP once and I liked it. I have yet to try the Halson, and
it has a few things that seem smart (like less flex).
Rick Brusuelas
Sun Library
Mark Obsniuk
No but I would ride down it on my Rockshoxs.
Mark, Rockshox forever
Gary W. Mahan
> This is what I was originaly responding to. Both have their pros and cons
>Agreed. I tell people that *I* prefer the Allsop to any of the air/oil
>or elastomer-based forks that I have tried so far (this list includes
>RS Mag21, Mag20, Quadra, Manitou, Scott, ProForx, and Trek). I have
>tried the AMP once and I liked it. I have yet to try the Halson, and
>it has a few things that seem smart (like less flex).
BZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZTTTTTTTTTTTT! (Damn mosquitos)
I relly like the "concept" (no pun intended) of the AMP fork.
This was the original fork I had planned on getting. The geometry
change would have been to dramatic (IMHO) on my bike. The price was
also a consideration.
It seems that a suspended fork like on the cannondales would be a good
compromise offering lower unsprung weight with a rigid fork and easily
adjustable. I think "Hannebrink" makes one of these (MBA article on
"monster bike").
Halson? what is this!
Rick Brusuelas
> I relly like the "concept" (no pun intended) of the AMP fork.
> This was the original fork I had planned on getting. The geometry
> change would have been to dramatic (IMHO) on my bike. The price was
> also a consideration.
Agreed again. The AMP (or Concept) fork adds over 1" to the
height of your bike, and changes the bike's geometry between
1-2 degree. The strengths (very limited fork flex, 2" travel,
lightweight) have to be balanced by the effect on geometry. Price
is fairly steep ($350-375), but if it works...
> It seems that a suspended fork like on the cannondales would be a good
> compromise offering lower unsprung weight with a rigid fork and easily
> adjustable. I think "Hannebrink" makes one of these (MBA article on
> "monster bike").
The Cannondale, Hanebrink, and ActionTec forks share the air/oil
design at the head tube design. Thus, they share the benefits
of rigid forks. But they also share the negatives of seal problems,
leakage. Plus, the Cannondale requires you to buy the Cannondale
bike (not that the bike is not a good one), and the Hanebrink and
ActionTec are both very expensive. Plus, I believe they may require
other changes in your bike.
> Halson? what is this!
Halson Inversion fork... the fork tubes are reversed so that the larger
tube is "on top". The "upper tube" has cut outs so that it can use
cantilevers. The Halson is similar to the Quadra in that it uses one long
elastomer instead of a stack. The fork has a "built-in" rubber sleeve
instead of boots and/or seals to protect the elastomer. Around $300.
Received good reviews... supposed to have fairly plush travel. Scot
Nicol (Ibis) has one on his personal bike.
Rick Brusuelas
Sun Library
Mark Erickson
Didn't Frishknecht (sp must be wrong) win the World Cup
on a Frankenstem? They must pay Team Ritchey a lot of dough
to use the stems if they really suck....
-maarrrk
p.s. I don't own an Allsop stem.
Rick Brusuelas
Ruthie Mathes also races for Team Ritchey, using a chromomly version
of the Allsop Frankenstem. She also won the 1992 World Cup. Other
Team Ritchey racers who use the Allsop include Tim Rutherford and
Warren Sallenbach. Henrik Djernis of Team Ritchey (and a leading
racer) used to use the Allsop, then switched to a fork (Tange Shockblades),
but I don't know if he switched back or not.
Carol Waters (Masters Div) races using the Girvin Flexstem on her Merlin.
She was quoted as saying the large front tire and the Girvin give her
enough suspension, but more importantly, she thought it insane to put
a fork on her bike that weighed more than the frame. She has recently
been signed to Team Mongoose, so I don't know what bike or suspension
she will use (perhaps the full-suspension Amplifier).
It is sometimes misleading to judge a product just by who races
with it. Most racers place greater demands on the product than most
of us will ever place. At the same time, they have mechanics dedicated
to making them work well, and also they get many new parts for each ride.
And some change products more for the commercial aspects. Afterall,
John Tomac has used Manitou, then Rock Shox, and now Tioga forks,
all in the last 3 years.
Rick Brusuelas
Sun Library
p.s. I *do* own an Allsop stem.
Stefan Scherrer
Yes, btw, I saw him (Thomas Frischknecht) winning the EUROPEAN Cross Country Championship last weekend. He did really well. I know from interviews that he principally prepares his bikes himself. You can take it for granted that he would not use an Allsop if it sucked!
p.s. I don't own an Allsop stem as well, but might intend to buy one.
--
---
Stefan Scherrer Phone : +41 1 257 45 76
Institut fuer Informatik Fax : +41 1 363 00 35
Universitaet Zuerich Telex : 817 251 unii ch
Michael M. Lee
>
[stuff deleted...]
>>
>> Didn't Frishknecht (sp must be wrong) win the World Cup
>> on a Frankenstem? They must pay Team Ritchey a lot of dough
>> to use the stems if they really suck....
>>
>It is sometimes misleading to judge a product just by who races
>with it. Most racers place greater demands on the product than most
>of us will ever place. At the same time, they have mechanics dedicated
>to making them work well, and also they get many new parts for each ride.
>And some change products more for the commercial aspects. Afterall,
>John Tomac has used Manitou, then Rock Shox, and now Tioga forks,
>all in the last 3 years.
>
I agree with this last statement. Riders are sponsered (read: paid) to use
certain products. I sometimes wonder how much a rider actually likes a product
versus how much the company is paying him/her. For example, when Wayne Croasda
le jumped ship from KHS to Specialized, was it because he didn't like the way
KHS bikes ride? or was it because Specialized offered more money? (or some oth
er reason) Does a rider nescessarily use equipment that s/he likes or is spons
ered to use? I'm not, however, saying that the two are mutually exclusive.
Gary W. Mahan
> >|> The stem is a bad idea. As far as I know it sucks.
> >
> >And if MBA told you to jump off a bridge, would you?
>
> on a Frankenstem? They must pay Team Ritchey a lot of dough
> to use the stems if they really suck....
>
>
> p.s. I don't own an Allsop stem.
>Yes, btw, I saw him (Thomas Frischknecht) winning the EUROPEAN Cross Country >Championship last weekend. He did really well. I know from interviews that he >principally prepares his bikes himself. You can take it for granted that he >would not use an Allsop if it sucked!
And if Thomas Frischknecht or Team Ritchey told you to jump off a bridge
would you? 8^)
>p.s. I don't own an Allsop stem as well, but might intend to buy one.
p.s I don't own a Allsop but I play one on TV!
Just a little Friday morning humor.
Keith Erskine
> > >The Allsop bobs horribly when sprinting out of the saddle. You cannot
> > >use your upper body at all for power generation with the Allsop. A
> > >Mag20 is much less annoying when pulling hard on the bars.
>
> Funny, I have had my Allsop for over six months now, and I don't
> "bob" at all when I climb, nor when I "stand and hammer" on
> flats. Seems to me that the frame, fork, and wheel stay quite
> rigid, which is definitely NOT true with a fork suspension. The
> stem stays at the top position. Do forks even have a "top position"?
I simply don't believe the stem doesn't bob when you stand and sprint
out of the saddle. If this really is the case, then you must not be
exerting any upper body torque, in which case you might as well just
stay in the saddle.
With a suspension fork, the connection from the handlebar to the pedals
IS rigid, so upper body force can be used to counteract the downward
thrust of the leg during a sprint, WITHOUT the stem bobbing up and down.
Yes, the fork will bob a little due to weight distribution changes, but
your upper body exertion does NOT go directly into moving the stem up
and down.
I should mention I am using these stems on road bikes as well as mountain
bikes. I used to be able to accelerate fairly powerfully on my road
bike to cover jumps and attacks, and I had a good sprint. After putting
the Allsop stem on, I had a hard time bridging gaps and sprinting because
I couldn't use my upper body effectively.
A fascinating data point: There was about as much techno-geek suspense
(hyuk, hyuk) as could be hoped for approaching the conclusion of the
'93 Paris Roubaix. Gilbert Duclos-Lasalle, a 36? year old rider for
GAN on Rock Shox, was in a 2 man break with Franco Ballerini, riding
an Allsop stem with a special lockout to make the stem rigid for sprints.
Gilbert didn't work the last several miles, sucking Ballerini's wheel.
Ballerini, a noted sprinter and young at ~26 years, was so sure he
could beat D-L he did nothing to try to shed D-L from his wheel.
Once in the stadium, with ~500m to the finish, D-L came around Ballerini
hard and took the lead. Ballerini began to close the gap, and they
were within 1" at the finish. Gilbert Duclos-Lasalle won!!!!!
An old rider with a shock fork beat a young sprinter with a rigid
fork and presumably locked out Allsop stem!!!!!
>
> > >Shock theory says "minimize unsprung weight". Obviously, the shock fork
> > >is much closer to this ideal than a shock stem. The weight of the whole
> > >bike & riders body helps smooth the ride on a shock fork bike, whereas
> > >the riders hands do all of the work to smooth out the ride on a shock stem.
> > Very important concept, Imagine a car with a rigid suspension but a
> > suspended seat!
>
> Yikes, this argument (as well as the motorycle argument) just does
> not apply with a bicycle, where the rider's weight is far greater than
> the vehicle (in this case, a bike).
This argument DOES apply. The weight of the rider is NOT all on the
handlebars, in fact very little of the weight is on the handlebars.
> > >The front wheel tracks the ground better with a shock fork.
> > Most definately!
>
> Bzzzzzt! Wrong answer again. The wheel hits a bump (log, rock, rut,
> whatever) and moves upwards, whether with a fork or a stem. The
> Allsop's 2-3" travel is unhindered by fork tube stiction or
> lockout threshold, so an argument could be made that it handles
> and tracks better than a fork.
I've never noticed stiction as a problem for anything except small
shocks that don't get absorbed. For a big 2-3" obstacle, the entire
bike gets jarred, and slowed down, with an Allsop stem. This
costs precious momentum. With a shock fork, the front wheel moves
up, and the momentum of the bike and rider is retained.
For rough terrain a shock fork is far superior to a shock stem.
One of my friends removed his Allsop stem and replaced it with a shock
fork for the very same reasons I'm going back to shock forks.
>
> And the one (1) degree geometry change caused by the RS's added
> length is significant in low speed steering. And this does not
> even discuss the reliability and maintenance benefits of the
> Allsop over air/oil or even elastomer shocks.
The Allsop stem requires maintenance. My aluminum Allsop squeaks badly
if I don't oil the pivot points every week.
>
> This is not to say that the Allsop is for everyone. But to dismiss
> it as a suspension alternative is a mistake. Team Ritchey uses it
> successfully. Leonard Zinn and Scot Nicol (Ibis) reviewed it
> very favorably in Velo News. And Joe Murray (Kona) uses it on his
> own bike over even his own suspension fork design (the Z-Link).
>
The stem works and is better than no suspension at all.
However, it is not far superior to shock forks, which is the
claim I was rebutting.
BTW, I LOVE the Allsop beam seat - that is an excellent concept,
excellently engineered, and makes for an incredibly soft ride.
My dream road bike is an Allsop PowerV frame, with beam seat, and a
BRC road shock fork up front.
Keith "suspension geek" Erskine
Keith Erskine
> |> >The front wheel tracks the ground better with a shock fork.
>
> Really? Then why are there such aftermarket products as Monster Fork Braces and
> SupperBubba Front Hubs?
Why are there products like titanium chains and titanium cogs? Because
somebody will pay $$$$$ if they think it is a competitive advantage.
I race mtbs and descend very aggresively. I never noticed independent
fork flex as a problem, except when I had the damping mismatched from
one side to the other.
The main reason a wheel tracks better with a shock fork is because
it is on the ground more, not getting bounced around on each obstacle.
It hugs the ground better is a better way of saying it.
Keith Erskine
kro...@cyberden.sf.ca.us
> >
> > >Mark Obsniuk sez:
> > >|> The stem is a bad idea. As far as I know it sucks.
> > >
> > >And if MBA told you to jump off a bridge, would you?
> >
> > Didn't Frishknecht (sp must be wrong) win the World Cup
> > on a Frankenstem? They must pay Team Ritchey a lot of dough
> > to use the stems if they really suck....
> >
> > -maarrrk
> >
> > p.s. I don't own an Allsop stem.
>
> Yes, btw, I saw him (Thomas Frischknecht) winning the EUROPEAN Cross Country
>
> --
> ---
> Stefan Scherrer Phone : +41 1 257 45 76
> Institut fuer Informatik Fax : +41 1 363 00 35
> Universitaet Zuerich Telex : 817 251 unii ch
My experience with the Allsop is pretty cool, though it clearly has its
drawbacks. Firstly, it provides a kind of floating support on the
handlebars. You just don't feel most of the small road shocks that a
stiff stem transmits so readily, and suspension forks probably do as well
given their natural stiction. On single track it's way cool, but when you
hit the really big stuff, craters and the like, it doesn't cope all that
well. Everything else is buffered pretty well with little loss of fork
rigidity (none in fact), but there is some lateral play in the
handlebars, which can affect your control, mine is a well-used stem
though and the newer ones may be much better in this respect.
Finally, though the bike geometry is unchanged, the rider positioning is
changed, so when you hit that sudden unexpected bump in the trail your
weight is thrown forward onto a spring loaded mechanism which can have
some surprising effects, meaning hold on to yer hats. All in all, I love
my stem for its all around usefulness, but for straight downhill bomber
runs there are times I wouldn't mind that air/oil cushion!
|||||||||||||*****************************||||||||||||||||||||||||||||
:::::::::TL Reed: Kro...@Cyberden.sf.ca.us :::::::::::::::::::::::::::
-----------(((((This Space For Rent - Cheap!)))))---------------------
Phil Calvin
>g...@spl1.spl.loral.com (Gary W. Mahan) writes:
>|> >The front wheel tracks the ground better with a shock fork.
>
>Really? Then why are there such aftermarket products as Monster Fork Braces and
>SupperBubba Front Hubs?
Pure hype, that's why! There will always be people with too much money
and not enough sense. That's why there is a market for titanium fork
braces. Titanium? it's flexible, so why would you want a brace made of it?
>It's to make up for the slop introduced by the
>independent fork legs. A ridgid fork will ALWAYS be more accurate than a
>suspension fork.
Maybe at the speed you ride. When I'm cruising with my suspension
forks over the rocky, rutted root-strewn single track around here,
watching my friends with rigid forks get bounced into the trees,
I have a hard time calling their forks more "accurate". I go where
I point the bike, regardless of the bumps. They don't!
> How you choose to absorb the bumps is up to you.
>
Again, RockShox work.
Phil
--
The opinions expressed are not necessarily those of the University of
North Carolina at Chapel Hill, the Campus Office for Information
Technology, or the Experimental Bulletin Board Service.
internet: laUNChpad.unc.edu or 152.2.22.80
bui tho xuan
an activated suspension stem might affect smooth cadence due to
the changing of the rider's body geometry (I read this in a mag.).
I got no answer, so I thought I'd repost.
Is it a real problem or is it just a rumor? I'd really like to know.
thanks.
tho
Rick Brusuelas
I this a serious question? I know a few of us that use Allsop's
reported that we do not notice performance-robbing "bobbing action"
when using the stem. Other riders, who prefer forks, argued that
the stem does result in a "bobbing action" (including a person who
said he used both and preferred the fork).
Which magazine article do you cite? MBA gave the Allsop a poor review,
concluding that it was an expensive comfort item, and not much better
than riding a rigid fork. Velo News (written by Leonard Zinn and
Scot Nicol of IBIS) reviewed it very positively, as did John
Kukoda of Bicycling Magazine).
It seems that the best, rather only way to settle this for yourself
is to try to ride one (preferably on the trail). Seemed to me
that there were a number of fine shops that sell the Allsop, and
most seemed quite helpful when it came to letting me test ride
bikes with it (most shops had at least one employee with the
stem on their bike who would offer to let me ride their bikes).
Plus, everybody I met on the trail let me try their bike (this
seems true of most people).
Rick Brusuelas
Sun Library
Christopher Solar
[snip]
: ...When I'm cruising with my suspension
: forks over the rocky, rutted root-strewn single track around here,
: watching my friends with rigid forks get bounced into the trees,
: I have a hard time calling their forks more "accurate". I go where
: I point the bike, regardless of the bumps. They don't!
Forgive me if I'm wrong, but...isn't it part of the idea of off-road
riding to use one's skill as a rider to manouver around the
various obstacles? I mean, if one had such a supple suspension system
that one could just plow straight through a trail, why bother? Why
not just take the bus tour?
--
Christopher Solar Bell-Northern Research Ltd. (613) 763-2862
"Lady, It's Bingo. You can't cheat at bingo. If I could, I would, but I can't.
I'm just lucky -- lucky to be in a town full of losers." -Satan in Highway 61
abwi...@bcsc02.gov.bc.ca
caused by a drop in the stem is almost un-noticeable. In fact, I would think
that the only way your cadence should be disrupted would be if the seat
height was changing???
al
Mark Obsniuk
and litespeed ti fork. But as I have just read about what really goes on and
have come back to reality I again say Frankenstem would suck.
Here goes a sort of recap of plus/minus of both types.
Forks/suspension
A-Better tracking of front wheel by means of being directly dampend(rockshox)
A-Better ability to sprint/climb/desend by means of the rider interface to the
bike does not change in realation ie pedal/bar/seat. ie: I like to ride trails
that when it is even but still somewhat rocky I stay on the seat and just
power away using my arms to pull back on the bars, push against the seat(ti
seat and post) so if the angles and distance was to change when going over
bumps that would cause problems.
A-Just feels right(Rockshox)
D-Can weigh more (2.4lb Mag 21 advertised)
D-Flex only to poor designs. Sure add oversized axle hub(cartridge bearings over come the friction of Shity Shimano hubs) I have a Kingsberry front hub(3 years old by the way with a mondo sized front hub axle) Brodie brace and brake brace I can ride with a setting of 1 and 6 and no brake rub at all and I really
rank on the bars when I ride.
Stem stuff
A-Weights less
A-Allows no height change in frame geometry
A-Neat to watch as you ride out of control in downhills.
D-Changes geometry if rider in relation to everything such as seat and pedals.
D-Unless you weight the stem it will not deflect on hits.
So it is sure easy to see that forks are better for all folks even roadies.
Here is a senerio for you which of the two gizmos will react better. You are
riding down a trail you are in a straight line up ahead there are some stutter
bumps and loose rock as you are about to enter a hairpin turn. You shift your
weight back to brake. So you now have your weight shifted back relative to a
normal riding position. As you come into the bumps the stem has less weight on
it so it it was the suspension it would move a proportionally small amount but
the fork is still bearing a good deal of the riders weight so when the bump
comes up it will have sufficient force to travel.
I hope that this makes sense and clears up the confusion so we can get back to
the battle of why there are companies who are wasting there time competing
against RockShox Mag 21 which is the most supperior fork on the market. Yes I
have riden many a forks.
RockShox forever
Mark
Mr. S.J. Wooding
: On a previous note, I posted a question on whether the motion of
It's a rumor, with little foundation. Moany of the people who perpetrate
such rumors haven't ridden a 'boingy' stem. Sure, it changes the riders
geometry, but by the time that change gets all the way from the bars to the
hips, it's negligible. If the stem is on an MtB, you get more drastic changes
just trail riding and shifting your weight around.
Don't believe the lies. Try one, you might like it!
Steve JW (MadBritishMountainBikerAndMaterialsScientist)
!faster and faster until the thrill of speed overcomes the fear of death!
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
S.J. Wooding (Yahoo!)
Radiation Damage Group __._. __.. O
Dept. of Materials Science and Engineering ____ ._.. /\,
University of Liverpool -|~(*)
PO Box 149 :::::::::. (*)
L69 3BX :::::::::::............
fax: (051) 794-4675 tel: (051) 794-5384 radd...@liv.ac.uk
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Rick Brusuelas
> Here goes a sort of recap of plus/minus of both types.
> Forks/suspension
>
What??? RS Mag 21 weighs 3.3 pounds!! How much money was required
to bring a RS down to 2.4 pounds??
> D-Flex only to poor designs. Sure add oversized axle hub(cartridge bearings
> overcome the friction of Shity Shimano hubs) I have a Kingsberry front hub
> (3 years old by the way with a mondo sized front hub axle) Brodie brace
> and brake brace I can ride with a setting of 1 and 6 and no brake rub at
> all and I really rank on the bars when I ride.
And how much more money was required to add the additional braces and rigid hub???
And what about:
D- raised front end of bike 3/4" to 1". This can effect low-speed
handling, ie. singletrack riding.
D- Costs more, even stock (and especially after all the ebove fixes to
problems caused by its very design)
D- Potential seal problems, preventive maintenance need
> Stem stuff
>
> A-Weights less
> A-Allows no height change in frame geometry
> A-Neat to watch as you ride out of control in downhills.
What??
> D-Changes geometry if rider in relation to everything such as seat and pedals.
> D-Unless you weight the stem it will not deflect on hits.
>
> So it is sure easy to see that forks are better for all folks even roadies.
>
> Here is a senerio for you which of the two gizmos will react better. You are
> riding down a trail you are in a straight line up ahead there are some stutter
> bumps and loose rock as you are about to enter a hairpin turn. You shift your
> weight back to brake. So you now have your weight shifted back relative to a
> normal riding position. As you come into the bumps the stem has less weight on
> it so it it was the suspension it would move a proportionally small amount but
> the fork is still bearing a good deal of the riders weight so when the bump
> comes up it will have sufficient force to travel.
If the rider is moving back to prepare to brake, how would more of his
weight stay on either suspension? In reality, the Allsop handles
stutter bumps than any suspension out there. The light action of the
Allsop reacts much faster than air/oil (see Bicyclings review of
Allsop, especially the MONSTER graph). Even most elastomer-based
suspension forks handle stutter bumps better than air/oil designs.
>
> I hope that this makes sense and clears up the confusion so we can get back to
> the battle of why there are companies who are wasting there time competing
> against RockShox Mag 21 which is the most supperior fork on the market. Yes I
> have riden many a forks.
>
> RockShox forever
>
> Mark
>
Paul Turner's son.
Mark Obsniuk
So I guess the lighter action of the stem would really help alot when you are
traveling at 40mph and you go over a couple of small rocks but how does it
handle large rocks say on the order of 6 inches in diameter. I ride a lot of
fast rock terrain.
So some people think that you weight the bars more then the pedals. When you
are riding you have the majority of your weight on the pedals. So the fork will
have an chance to be at work at all times. The stem needs a certain amount
of force if it is too easy to have travel then that is no good. The main
problem that I would have with the stem is fact that it does not allow the same
degree of bike control in terms of keeping the wheel in contact with the ground.
When the rear wheel hits a bump that causes the fork to slightly depress. A stem
would not do that unless the rider was stupid enough to have all his weight on
the bloody thing. My Litespeed stem takes out alot of the small stuff that my
forks don't. I can not wait to get my 2.4 lb Mag 21s.
RockShox forever
Mark
Rick Brusuelas
> So I guess the lighter action of the stem would really help alot when you are
> traveling at 40mph and you go over a couple of small rocks but how does it
> handle large rocks say on the order of 6 inches in diameter. I ride a lot of
> fast rock terrain.
The Allsop gets between 2-3" of travel (versus less than 2" for most fork
suspensions), so it has plenty of ability to take on the large stuff
as well. I would concede that Mag21 take on big hits better than
the Allsop, but at what cost (both in overall ride and $$$)?
Incidentally, in my experience I have found that the fastest line
is the smoothest line. I tend to try to avoid the truly gigantic rocks.
> So some people think that you weight the bars more then the pedals. When you
> are riding you have the majority of your weight on the pedals. So the fork will
> have an chance to be at work at all times. The stem needs a certain amount
> of force if it is too easy to have travel then that is no good. The main
> problem that I would have with the stem is fact that it does not allow the same
> degree of bike control in terms of keeping the wheel in contact with the ground.
> When the rear wheel hits a bump that causes the fork to slightly depress. A stem
> would not do that unless the rider was stupid enough to have all his weight on
> the bloody thing. My Litespeed stem takes out alot of the small stuff that my
> forks don't. I can not wait to get my 2.4 lb Mag 21s.
Well, its nice to see that your expensive bike and probably equally expensive
modified RS Mag21 ride well :-). Most of us can't afford this, so we
will limp along with our steel bikes and affordable suspension ;-).
But you never answered the question, how much (on top of the RS Mag21
fork price) are you spending to get suspension that is light as the Allsop?
Rick Brusuelas
Sun Library
Mark Obsniuk
>In article 7469...@sfu.ca, mobs...@malibu.sfu.ca (Mark Obsniuk) writes:
>> So I guess the lighter action of the stem would really help alot when you are
>> traveling at 40mph and you go over a couple of small rocks but how does it
>> handle large rocks say on the order of 6 inches in diameter. I ride a lot of
>> fast rock terrain.
>The Allsop gets between 2-3" of travel (versus less than 2" for most fork
>suspensions), so it has plenty of ability to take on the large stuff
>as well. I would concede that Mag21 take on big hits better than
>the Allsop, but at what cost (both in overall ride and $$$)?
>Incidentally, in my experience I have found that the fastest line
>is the smoothest line. I tend to try to avoid the truly gigantic rocks.
That is avoiding the truly gigantic rocks.
>
>> So some people think that you weight the bars more then the pedals. When you
>> are riding you have the majority of your weight on the pedals. So the fork will
>> have an chance to be at work at all times. The stem needs a certain amount
>> of force if it is too easy to have travel then that is no good. The main
>> problem that I would have with the stem is fact that it does not allow the same
>> degree of bike control in terms of keeping the wheel in contact with the ground.
>> When the rear wheel hits a bump that causes the fork to slightly depress. A stem
>> would not do that unless the rider was stupid enough to have all his weight on
>> the bloody thing. My Litespeed stem takes out alot of the small stuff that my
>> forks don't. I can not wait to get my 2.4 lb Mag 21s.
>Well, its nice to see that your expensive bike and probably equally expensive
>modified RS Mag21 ride well :-). Most of us can't afford this, so we
>will limp along with our steel bikes and affordable suspension ;-).
>But you never answered the question, how much (on top of the RS Mag21
>fork price) are you spending to get suspension that is light as the Allsop?
I have not spent very much I baught my ti stem and paid $195 Canadian. All of
my stuff for my bike has been purchased over the last three years. I am just as
frugal as the next guy is. I have purchased the following shit from the cheapest
source available.
Litespeed 17" frame - $1300 a
Syncros ti bb - $100 c
Sncros crankomatic - $20
Syncros ti post - $95 c
Scott at-slf bar - $100 c(couldn't wait)
Litespeed stem - $195
Kinsberry hubs - $175 c but front only now
ultegra rear 8sp - $75
XTR cassette - $60
XT crank - $100
Clipless xt - $ 150?
Rockshox - $450
flite seat - $ ?
grip shift - $70a
Dia-compe ss-7 - $35 c
986 rear brake - $ 20 a
the list goes for a while yet but that is not my point.
I have stated that the 2.4 lb is coming out and I might get it. But now that mytop out bushing is warrantied I think that I will keep it for a while yet.
I just can not believe in a system that operates only by the weight on the bars
if I am missing something in that theory please let me know but until then I
will be adement on my theory that forks will be more active while riding then
the stem in terms of consructive travel. Such as when the rear wheel hits an
object, you are on a flat and you are not weighting the bars much but you still
have some weight on the pedals which in turn weigh down the fork allowing it to
have suffiecent force to move. Sure if a rider was standing and desending the
stem could easily move. But that never happens the rider is sitting standing
forward and backwards on the bike so the stem would be inactive for what could
amount to at least %50 of the time.
But the other point is the triangular relationship between bar/pedals/seat. The
stem does not allow for this to occur it will change up to 3". I don't know
about you but that is a big change. Sure a fork will weigh more but I don't
recall people rushing out and buying one for doing downhills. Try some real
single track and you will see that changing the relationship of the rider to
bike as in the stem will make for poor handling. The fork if dialed in right
will sage on hits and severe braking but the rider will still maintain a
constant ratio with the bike itself.
Mark
ron g macdonald
>Forgive me if I'm wrong, but...isn't it part of the idea of off-road
>riding to use one's skill as a rider to manouver around the
>various obstacles? I mean, if one had such a supple suspension system
>that one could just plow straight through a trail, why bother? Why
>not just take the bus tour?
I'd say yes, that is PART of the idea. Going fast over things you can't
avoid is another part. That's when I'm glad to have 2" of elastomer
between me and the obstacle.
Ron MacDonald
Rick Brusuelas
> I have not spent very much I baught my ti stem and paid $195 Canadian. All of
> my stuff for my bike has been purchased over the last three years. I am just as
> frugal as the next guy is. I have purchased the following shit from the cheapest
> Rockshox - $450 ****
> Kinsberry hubs - $175 c but front only now *****
> Syncros ti post - $95 c
>
> I have stated that the 2.4 lb is coming out and I might get it. But now that
Whew! Looks like a nice bike, and should be at its dollar value (not
criticizing you, mind you, rather envious). But keep in mind the dollar
outlay required to get a nice *light* suspended bike (especially note
the initial outlay on the RS, then the additional $175 to resolve
the hub problem, then another $95 to lighten the front end further).
I spent:
92 Bridgestone MB-3 $650 (big sale)
Scott AT3 LF 40 (needed bar-ends, and like the shape)
Ritchey ZMAX WCS 60 (lighter and better grip)
Avocet Air O@ (ti) 80 (my only titanium concession, but very comfy)
Allsop 250 (included installation)
Total $1,000 (yikes... I spent a grand?!) @ 27 pounds
Now, my point is that there is no one suspension that is perfect
for everyone. The Allsop added minimal weight on my fairly heavy
bike. The Rock Shox would have added more, and would have
effected the bike's handling adversely in the one area I like
to ride the most... singletrack. Where the Mag21 works better
(downhill big hits) I will either slow down, steer around, or
just take the bump head on and ride on.
I had a nice light fork, a relatively heavy stem, and a fairly
absorbant frame. The stem seemed to make sense. If I had a
heavy stiff fork, and a light stem, then I would have considered
a suspension fork.
I rode Rock Shox (Quadra and Mag21). I rode Manitou. I rode
ProForx. I chose Allsop.
Rick Brusuelas
Sun Library
PS: If Rock Shox could really come out with a lighter
version of the Mag21, without charging big $$$, then
even I would be interested ;-). But I fear a 2.4 lb
version would be ti-intensive, and thus cost mucho
dinero.
PPS: Sorry to use up so many cycles on this. I imagine
Mark will throw in one more ad for Rock Shox, and then
we can return you all to the sleeping crotch and
highest gear ratio postings. :-)
Rick Brusuelas
> I'd say yes, that is PART of the idea. Going fast over things you can't
> avoid is another part. That's when I'm glad to have 2" of elastomer
> between me and the obstacle.
2 inches in travel?? The Halson is supposed to get 1.9 inches
from a fairly large elastomer. The Manitous probably max out
at 1 3/4". I have heard that the Quadras get 2", but in my
two tries with it it measured less than 1 3/4". The
ProForx got the closest in my test rides. The Tange Shockblades/
Antigravity/Struts are lucky to get 1.5".
Did you uncover a new elastomer shock that really got 2"?? What
brand?
Rick Brusuelas
Sun Library
PS: suspension travel, like fork weight, must be one of the
least honest specs reported (see MBA article a few months back
on actual weights of forks).
Daniel MacDougall
: PS: If Rock Shox could really come out with a lighter
: even I would be interested ;-). But I fear a 2.4 lb
: version would be ti-intensive, and thus cost mucho
: dinero.
Yes, the new RS "SL" has some ti in it -- ti steerer, Easton aluminum
stanchions, etc... see MBA, July 1993, page 15. In July, the expected
price was going to be around $600! And how 'bout this -- same page,
Scott forks with carbon fiber legs, at 2.3 lb!! :P
: help
Gary W. Mahan
>riding to use one's skill as a rider to manouver around the
>various obstacles? I mean, if one had such a supple suspension system
>that one could just plow straight through a trail, why bother? Why
>not just take the bus tour?
Yes that is the fundamental principle, but as you raise your speed
you cant avoid as much and tend to hit more (especially on a new trail).
So the idea is to hit as "little as possible". The more your bike will absorb
the "little as possible" stuff, the faster you can go and the less you can avoid etc..........
Mark Beardslee
Just to add a little information to the discussion, I talked to a
Rock Shox guy at Mammoth last month about the new light weight
fork they are coming out with.
It is called the SL, I assume for "super light" and sould be out soon.
The differences between the SL and MAG 21 are:
1. It uses thick aluminum tubes in the steerer and the sanction (sp?)
tubes. He said that titanium was to flexy and that Al is stiff
and still lighter even at the required thickness.
2. Light weight fork crown -- I'm not sure about the material.
3. Light weight fork brace made out of Al Metal matrix material.
4. Titanium bolts etc.
As for non-functional differences, it uses the magnesium sliders from
the MAG 21 except that they are polished to a shiny gold color instead
of painted. They look pretty cool.
They are also going to have a retro-fit kit for the MAG 21, but I
don't know about any other RS models.
He said that the SL is a pound less that the mag 21 so the 2.4 Lb
weight is probably fairly accurate (as far as any manufacturers claimed
weights can be believed.)
Now for the bad part, the price will be "about 200 dollars more than
the MAG 21" (his quote.) Which makes the list price... drum roll
please.. $589. Maybe less from some mail order places.
SIX HUNDRED DOLLARS for a fork.
From a personal perspective, after dissassembly, it seemed to me that
most of the weight of the mag 21 is in the steerer tube and fork
crown, so maybe just replacing these parts would be a major win for a
reasonable price.
-Mark
Mark Chandler
>
>Just to add a little information to the discussion, I talked to a
>Rock Shox guy at Mammoth last month about the new light weight
>fork they are coming out with.
>
>It is called the SL, I assume for "super light" and sould be out soon.
>The differences between the SL and MAG 21 are:
>
>1. It uses thick aluminum tubes in the steerer and the sanction (sp?)
> tubes. He said that titanium was to flexy and that Al is stiff
> and still lighter even at the required thickness.
Is it AheadSet-only? I'd be *very* leery of an Al steerer paired
with a conventional (expanding) stem.
> -Mark
--
Mark Chandler Novell, Inc. 510/975-4522
chan...@wc.novell.com Walnut Creek, CA AOL: Crosswords
===============================================================
The opinions expressed above are mine, not my employer's.
Mark Beardslee
chan...@wc.novell.com (Mark Chandler) writes:
> In article <265b0r$k...@agate.berkeley.edu> bea...@curry.Berkeley.EDU (Mark Bea
rd
> slee) writes:
> >
> >Just to add a little information to the discussion, I talked to a
> >Rock Shox guy at Mammoth last month about the new light weight
> >fork they are coming out with.
> >
> >It is called the SL, I assume for "super light" and sould be out soon.
> >The differences between the SL and MAG 21 are:
> >
> >1. It uses thick aluminum tubes in the steerer and the sanction (sp?)
> > tubes. He said that titanium was to flexy and that Al is stiff
> > and still lighter even at the required thickness.
>
> Is it AheadSet-only? I'd be *very* leery of an Al steerer paired
> with a conventional (expanding) stem.
Good point, the one I saw was ahead-set style. There might
be a problem with using stem expander, and there also might be a
problem with threading the steerer for a regular headset. The threads
in an Al steerer might not be rugged enough. I am sure that he said
the steerer is Al, in fact the one I saw had such a thick steerer that
the standard stem quil might not even fit inside it. However, this is
speculation.
-Mark
Rick Brusuelas
$600!! Almost more than my current bike (and *more* than the
frame I hope to buy soon). Oh well...
Rick Brusuelas
Sun Library
Matt Bushore
A merely academic point, I dont believe the 21SL I fondled last thursday
had a Ti steerer. The steerers are 7000 series aluminum, and available only
for Aheadset.All bolts are Ti
Threading them would cause a stress riser (how do you use that in context?)
anyway, make them weak where they are threaded. They said they have
been tested, and may be stronger than the 21's. Also have
a mag brace, The AL upper tubes are available as a retrofit on the 21's.
--
Matt Bushore
'Don't worry about life, it's not permanent'
--
Matt Bushore
'Don't worry about life, it's not permanent'
bui tho xuan
>Just to add a little information to the discussion, I talked to a
>Rock Shox guy at Mammoth last month about the new light weight
>fork they are coming out with.
>It is called the SL, I assume for "super light" and sould be out soon.
> tubes. He said that titanium was to flexy and that Al is stiff
> and still lighter even at the required thickness.
Hi y'all.
if I understand the above correctly, then the guy is wrong; and I hope
that he's not the designer of the fork.
The geometrical constraints of the steerer tube for most forks are
fixed: the outside must be small enough to fit the bearing races,
and the inside must be large enough for the handlebar stem.
As such, a steerer tube out of Ti will be considerably stiffer than
one made of aluminum alloys.
The only possible option is to use Ahead systems only steerer tubes,
and then increase the thickness of the aluminum tube. But I doubt if
there is any change in stiffness with respect to weight. The strength
is decreased.
The driving force for the choice of material used is most likely
(their) cost reduction, not (your) performance.
Opinions, anyone?
tho
Mark Obsniuk
>Whew! Looks like a nice bike, and should be at its dollar value (not
>criticizing you, mind you, rather envious). But keep in mind the dollar
>outlay required to get a nice *light* suspended bike (especially note
>the initial outlay on the RS, then the additional $175 to resolve
>the hub problem, then another $95 to lighten the front end further).
>I spent:
I baught the hubs becuase I did not want a steel axle, by the way this was
before I even new there was Rockshox or any other fork. And I have a rear hub
with that so it is not $174 for a front hub. The stem same thing no suspension
just something to change from what I had before suspension came out.
>92 Bridgestone MB-3 $650 (big sale)
>Scott AT3 LF 40 (needed bar-ends, and like the shape)
>Ritchey ZMAX WCS 60 (lighter and better grip)
>Avocet Air O@ (ti) 80 (my only titanium concession, but very comfy)
>Allsop 250 (included installation)
>Total $1,000 (yikes... I spent a grand?!) @ 27 pounds
My bike weighs under 21 lbs and it is not wimpy by any means. I weigh 180lbs
and have riden on the thing for 3 years now and not a single part failure. I am
now running 15 gauge double butted Wheelsmith spokes in the rear. Not a single
problem so far. My front wheel is three years old and only trued 5 times. I havespent alot of money on my bike but it is only for something that would improve
its ride or make it perform better.
>Now, my point is that there is no one suspension that is perfect
>for everyone. The Allsop added minimal weight on my fairly heavy
>bike. The Rock Shox would have added more, and would have
>effected the bike's handling adversely in the one area I like
>to ride the most... singletrack. Where the Mag21 works better
>(downhill big hits) I will either slow down, steer around, or
>just take the bump head on and ride on.
Single track should show the problems of the stem the most.
>I had a nice light fork, a relatively heavy stem, and a fairly
>absorbant frame. The stem seemed to make sense. If I had a
>heavy stiff fork, and a light stem, then I would have considered
>a suspension fork.
>I rode Rock Shox (Quadra and Mag21). I rode Manitou. I rode
>ProForx. I chose Allsop.
>Rick Brusuelas
>Sun Library
>PS: If Rock Shox could really come out with a lighter
>version of the Mag21, without charging big $$$, then
>even I would be interested ;-). But I fear a 2.4 lb
>version would be ti-intensive, and thus cost mucho
>dinero.
>PPS: Sorry to use up so many cycles on this. I imagine
>Mark will throw in one more ad for Rock Shox, and then
>we can return you all to the sleeping crotch and
>highest gear ratio postings. :-)
Well on that front I have not bothered to read those but here is my say since
you asked.
Highest gear you ask take a metal pulley wheel attach it to the cassete ( there
is always a way ) And then find the biggest front chain ring available. I think
that I heard that that might be at least 68. So that works out to a ratio of
6.8 or mtb - 176 or roadie - 190 or so.
Sleeping crotch well you should get off the bloddy seat once in a while lame
brains.
Oh I just thought of a variation to that idea of the gear ratio but that will
have to wait.
Mark
Bruce Rowen
Having niether a suspension fork or stem (but seriously considering
one), what would be the best device in this situation:
Some of the trails I ride are severly washboard. Sometimes when I am
at a paticular speed, the washboard will cut my speed down just as
fast as running into soft sand. It's almost like running into a wall,
you go from 30 mph to 5 mph in a fraction of a second. Almost to the
point of going over the bars. It does not make any difference how much
weight I am putting on the bars. (MB-2 with Logic fork)
My guess is that a suspension fork would work to not only soften the
blows to the rider, but also allow the bike to glide over the
washboard without resonating. A suspension stem seems like it is just
a suspension for the rider; it does nothing to help improve the bikes
ability to track over bumps.
On a side note:
Where do these plow operators go to school? At least one local operator
has the uncanny ability to produce washboard surfaces in soft sand!
The two things I hate most riding are washboard and soft sand, now
they can produce it in combination! Is there special instruction for
this? Can we hang the instructor?
--
-------------------------------------------------------------------------------
Bruce Rowen National Radio Astronomy Observatory
Scientific Programmer Array Operations Center
bro...@aoc.nrao.edu P.O. Box O Socorro, NM 87801
(505)385-7329 (505)385-7000
-------------------------------------------------------------------------------
Yu-Shan Chin
|> In article H...@world.std.com, r...@world.std.com (ron g macdonald) writes:
|> > I'd say yes, that is PART of the idea. Going fast over things you can't
|> > avoid is another part. That's when I'm glad to have 2" of elastomer
|> > between me and the obstacle.
|>
|> 2 inches in travel?? The Halson is supposed to get 1.9 inches
|> from a fairly large elastomer. The Manitous probably max out
|> at 1 3/4". I have heard that the Quadras get 2", but in my
|> two tries with it it measured less than 1 3/4". The
|> ProForx got the closest in my test rides. The Tange Shockblades/
|> Antigravity/Struts are lucky to get 1.5".
I've maxed out my Manitou I several times and each time
that I measured it, it was about 1.9 inches.
Sam
Jim Collias
6" rocks at 40 mph? You must win every race.
Rick Brusuelas
>
> My guess is that a suspension fork would work to not only soften the
> blows to the rider, but also allow the bike to glide over the
> washboard without resonating. A suspension stem seems like it is just
> a suspension for the rider; it does nothing to help improve the bikes
> ability to track over bumps.
Well, true to a certain extent, but not completely. Remember that your
body is by far the heaviest "part" attached to your bike. Since the impact
is being lessened by the give between you and your bike, the "shock"
to the bike frame will be reduced to a certain extent. And the bike will
then be able to "track over the bumps" better.
At the same time, a suspension fork will also only absorb some of the
"shock" tranmsitted through the frame. But I concede a fork will
absorb more than a stem will.
Yes, the amount of "abuse" my bike takes now is greater now that I
use the Allsop, since I ride much faster through the rough stuff
with the suspension stem. But the bike seems to be no worse for
wear in the eight months I have ridden with it (no increase in the
need for spoke truing, no sudden cracks in the frame, etc). I
did notice the cages "rattled" more (until I removed them when I
bought a Camelback :-).
Gary W. Mahan
>one), what would be the best device in this situation:
>Some of the trails I ride are severly washboard. Sometimes when I am
>at a paticular speed, the washboard will cut my speed down just as
>fast as running into soft sand. It's almost like running into a wall,
>you go from 30 mph to 5 mph in a fraction of a second. Almost to the
>point of going over the bars. It does not make any difference how much
>weight I am putting on the bars. (MB-2 with Logic fork)
>My guess is that a suspension fork would work to not only soften the
>blows to the rider, but also allow the bike to glide over the
>washboard without resonating. A suspension stem seems like it is just
>a suspension for the rider; it does nothing to help improve the bikes
>ability to track over bumps.
Both should allow you to go faster (Wow, hitting washboard surface
slows you from 30 to 5). The fork will probably have a slight edge.
You will still get resonance from the bike with either setup. But
moreso (sp? or just bad english) with the stem(a very careful IMHO).
I still get resonance from my bike with RS Quadra (boooh, hisss)
but now it starts at the back tire. The fact that I am
traveling much faster 8^),8^) (big smily face) might also be a
major contributing factor.
Mike Fike, Manchester, Maine
In article <BROWEN.93...@lyapunov.aoc.nrao.edu>, bro...@lyapunov.aoc.nrao.edu (Bruce Rowen) writes...
>
>Having niether a suspension fork or stem (but seriously considering
>one), what would be the best device in this situation:
>
>Some of the trails I ride are severly washboard. Sometimes when I am
>at a paticular speed, the washboard will cut my speed down just as
>fast as running into soft sand. It's almost like running into a wall,
>you go from 30 mph to 5 mph in a fraction of a second. Almost to the
>point of going over the bars. It does not make any difference how much
>weight I am putting on the bars. (MB-2 with Logic fork)
>
>My guess is that a suspension fork would work to not only soften the
>blows to the rider, but also allow the bike to glide over the
>washboard without resonating. A suspension stem seems like it is just
>a suspension for the rider; it does nothing to help improve the bikes
>ability to track over bumps.
I chose an AMP fork. It is similar in concept to the Allsop stem
(parallelogram), except that the suspension parts are mounted between the
rigid one-piece fork and the headtube. I find it extremely useful on the
washboard dirt roads. I ride with a friend who has no suspension and he has
to practically stop to be able to ride on washboard because his eyes can
barely focus- the bumps come so fast- and he has come close to losing control
of the steering due to the stutter bumps. I still feel the stutter bumps, but
nowhere near what it used to be like; I can still maintain speed and pedaling
motion. It's not plush, but very ridable. I also like the fact that the AMP
tracks very nicely on the singletrack- It feels as responsive a my rigid did.
So as not to spray gas on the Allsop/Mag21 fires let me say this;
The AMP works, the Mag21 works, the Allsop works, the Manitou works- It comes
down to how you ride, what you ride, where you ride, how much you want to
spend and what qualities are most important to you. Suspension will now cost
you anywhere from $159 (very low end stuff) to $600 (VERY high end stuff) with
lots of good choices in the $250-$350 range. Get what pleases you. Don't get
hung up in what's "best". It's different for everyone.
Mike
********************************************************************************
Mike Fike * No comment until I see a lawyer....
17 Myrtle St. *
Manchester, Maine, 04351 *
********************************************************************************
Akkana Peck
I get the impression that suspension stems might have an advantage
for lighter riders. Maybe that's just a function of the suspension
systems I've been able to test-ride: the Trek fork (the one that comes
stock on a 9800, whatever that is), Mag20, Mag21, AMP, and Frankenstem.
All of the above were ridden on bikes that were too big for me, which
affects the test significantly; the Mag20 and AMP were on bikes that were
WAY too big for me. All were set up for heavier riders.
I should mention that I was somewhat prejudiced in favor of the AMP,
because it's light and generally cool and I really wanted to like it,
and against the Frankenstem, because I have a healthy appreciation for
the difference between spring/unsprung weight and logically I can't
convince myself that a suspension stem should work as well as a fork.
After riding each of these, though, I found that the stem was the only
one of the bunch that made a noticable difference to the way the bike
handled. None of the suspension forks gave any significant compression
when I rode them, no matter how hard I sought out bumps. If I stand over
a bike with one of these forks, apply the front brake and push down
sharply with all my weight, I can get a slight deflection (half an inch?)
but while riding, I've trained myself not to put much weight on the bars
(downhill bombing runs on a rigid Cannondale do teach you some good
habits :-), and unless you lean on the bars, suspension forks don't seem
to do anything. The Frankenstem did make a noticable difference, though;
I'm not sure whether that was because it was very soft compared to the
forks (which it was) or because the forks have too much stiction.
Someday I'd like to try riding a suspension-fork bike that's the right
size for me, and see if that makes a difference (think Lisa Muhich might
be willing to loan me her bike for a few hours? :-) Dream on ...
I'm not a complete convert to the Allsop camp (partly because I'm
becoming increasingly convinced that suspension is a crutch and I
shouldn't get any form of suspension until I've learned all this rigid
bike has to teach me), but riding the stem definitely made me consider
it much more seriously as an alternative to suspension forks.
...Akkana akk...@moab.wpd.sgi.com
Cannondale M700 "Killer Vee" pilot akk...@netcom.com
Charles (skip) W. Manry Jr.
>
> So as not to spray gas on the Allsop/Mag21 fires let me say this;
>The AMP works, the Mag21 works, the Allsop works, the Manitou works- It comes
>down to how you ride, what you ride, where you ride, how much you want to
>spend and what qualities are most important to you. Suspension will now cost
>you anywhere from $159 (very low end stuff) to $600 (VERY high end stuff) with
>lots of good choices in the $250-$350 range. Get what pleases you. Don't get
>hung up in what's "best". It's different for everyone.
>
Yea! I have been wanting to say something like this for awhile now. Ride it
all, if possible, and then make your choice. For me I got the stem due to
cost, weight, ease of maintainence, PLUS: the type of trails around here.
If I were in an area that had tons o' roots and rocks I would have chosen
the RS Quadra, but I don't. Where I live and ride the trails are mostly dirt
with the occasional rock, root, etc. Thus the stem!
--
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Charles (skip) W. Manry / cma...@eecs.wsu.edu % Nothin's worse than %
% Dept of Electrical Engineering and Computer Sci. % having a scratch you %
% Washington State University, Pullman WA 99164-2752 % can't itch! %
% ** Opinions expressed here do not in any way ** % %
% ** reflect that of my department or supervisors ** % From: Bladerunner %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Brooke Fabricant
: 6" rocks at 40 mph? You must win every race.
...your 6" might not be his 6"....
brooke.
Mark Obsniuk
from the author about how he discovered Tom Ritcheys idea about suspesion.
The referance was about how you could ride a cross bike in the areas that he
rides in. If you recall Tom has also staed that he has ridden his "road" bike
in these trails also. I would really like to see Tom here in Vancouver riding
some real trails.
Mark