Carbon fork and/or handlebar for tandem?
Monkey Boy
steel fork. I know carbon is lighter but would we see other benefits
going to carbon fork and/or handlebars? Input appreciated.
li...@jkassen.org
> My wife & I purchased a steel Co-Motion tandem this summer. It has a
> steel fork. I know carbon is lighter but would we see other benefits
> going to carbon fork and/or handlebars? Input appreciated.
FWIW, I commute on and have ridden brevets on the Nashbar cross carbon fork. It has mounts for a disk brake, which I use. The fork is just as if not heavier then my quality steel forks. I'd never trust anything less beefy then that hunk of plastic for a tandem, let alone my own single bikes.
As for carbon bars, are you really that interested in saving weight? Even the lightest carbon bars ain't that much heaver then decent aluminum bars.
I'm pretty anti-carbon for critical parts like forks and handlebars. I shudder to think of results of having a fork or bars shatter when riding a tandem -- you'd be hard pressed to find a more catastrophic failure mode. Stem or front wheel perhaps?
Jake "snap!" Kassen
li...@jkassen.org
> My wife & I purchased a steel Co-Motion tandem this summer. It has a
> steel fork. I know carbon is lighter but would we see other benefits
> going to carbon fork and/or handlebars? Input appreciated.
One more thing -- While I'm sure there are some great photos of busted steel and AL parts, the photos on the site linked below are pretty spectacular, if not humorous:
Jake "Not necessarily representative" Kassen
Donald Perley
switching to carbon.
Ingle, Bruce
Sheldon Brown once noted that the best fork for a frame is usually the
one that's supplied with it. It's probably not worth replacing unless
it's ridiculously heavy or been bent in a crash.
> ...Nashbar cross carbon fork. It has mounts for a disk brake,
> which I use. The fork is just as if not heavier then my
> quality steel forks. I'd never trust anything less beefy
> then that hunk of plastic
Apparently your trust is justified...from:
http://www.nashbar.com/bikes/Product_10053_10052_175019_-1_201511_10000_
201514
> I should note, I am so pleased, I got my brother one.
> In a sad twist of fate, my brother left his bike on top
> of his car and tried to drive into the garage, ouch! If
> you are wondering about the strength of this fork, The
> garage incident bent the roof rack, bent the head tube
> on the bike, bent the steer tube on the fork, But the
> carbon lowers were fine. No cracks, this is one tough cookie.
> I'm pretty anti-carbon for critical parts
Personally, I've managed to fracture critical components of the other
three commonly used structural materials since August (and luckily
stayed out of the ER). I've yet to fracture a carbon-reinforced plastic
component (knock on composite), and it's certainly not from lack of
opportunity; I made my best attempt at fracturing a CRP bar in 2005
after squashing it with a split-clamp stem, and had no luck.
I had been seriously considering replacing the all-CRP fork on my randon
bike with steel after snapping off a pedal, but I've since come to the
understanding that no material is immune to fracture. With my luck, I'd
pay big bucks for a "safer" lightweight steel fork only to have it snap
off instead. The fork I have has certainly survived any potential
infant mortality and rides fine; unless I can identify a potential
problem, I may as well keep using it.
- Bruce
DrCodfish
"....I know carbon is lighter but would we see other benefits going to
a few up spec parts at no addition cost.
It came with a Wound Up tandem fork. Just looking at it I was very
skeptical, I never thought much of the Wound Up design when they first
came out and I had the opinion that on a tendem it was a bad idea.
Still, the DeVinci is a pretty well thought out piece of equipment and
the dealer assured me that the fork was the "tandem model". I would
not say I am a retro-grouche, but considering my weight and our uses,
saving a half pound or so on the bike isn't rally going to make a big
difference in our times, or so I thought.
Probably right, but what I did not factor in was the performance
characteristics of the fork. I'm more rhino than gazelle so all the
talk af how tires, or forks, or bars 'feel' is lost on me, I'm just
not that sensitive. The Wound Up fork makes such a difference in
handling and performanace that even I can 'feel' it. That old
expression 'like riding on rails' comes to mind. the way it responds
to the inputs, the feed back it gives in a turn really increases my
confidence which is extremely important to me when I have my most
precious cargo in back pumping away on the pedals. It is rock solid in
a descending corner, but not like a brick wall, more like a well
suspended muscle car of the 70's. I don't know if you ever drove a
well tuned Dodge Challenger back in the late 60's or early 70's but
that's what came to my mind the first time we came off knee buster
pass. Solid, but really smooth.
I have no idea what it would cost but if you are dead set on upgrading
your fork, I would strongly recommend you look at the Wound Up. It
may even be as heay or heavier than your current fork I don't know,
but it would probably be an excellent 'performace' upgrade.
As for the bars I'm with Jake. This is similar to putting Titanium
chain ring bolts on to save weight, and if you care that much about
weight you should have just jumped off the cliff and gotten a Calfee
all carbon two seater.
Yr Pal Dr C
PS: Come to think of it those Ti bolts probably do work out: Not only
do you save the weight of those steel bolts, you also save the weight
of all those 20 dollar bills on your wallet.
PPS: Have you discovered tandem@Hobbs yet? You'll get a some good
info (and a lot of opinion) there.
PCH Rando
While I have put in some distance with a carbon fork on my single and
I am in no way anti-carbon, I would like to say that I am pretty
comfortable with my steel fork on my tandem.
We rode PBP with an aluminium Santana Sovereign with a steel fork.
Vibration was an issue, but with some Grand Bois tires and Specialized
Bar Phat handlebar tape, it had minimal impact. If someone purchased
a carbon fork for me I would put it on the Santana that we now use for
rides with the kids as stokers to see if it helps.
We purchased a custom Steve Rex steel tandem & fork with couplers
after coming back from PBP as we were pretty frustrated with the
Santana on PBP for a number of reasons. When we ordered the bike, we
told Steve that since we climb slow we tend to descend relatively
quickly we would like a geometry that would be stable at higher
speeds. We live in Southern California where descents of 25+ miles
near 5% are not unheard of. On these descents we tend to build up
some speed and hold it for a long time.
I can not tell you how happy I am with the stability at speed (20 to
holy crap!) that our Steve Rex has. I imagine it is a ride similar to
a Goldwing Motocycle - it is very smooth and stable at speed. Very
comfortable. Corners well. On the other hand it is a little more
difficult to control on the super steep uphill climbs (4 mph and
below) since it has a little more "flop" but I do not consider it to
be a significant issue since I am used to it now. At speeds between 4
and 20 it still has a better ride than any bike that I have, although,
my wife's Specialized Roubaix (full carbon) single gives it a good run
for its' money.
I guess what I am really saying is that while the frame/fork material
has a significant impact on ride quality, so does frame geometry.
That could also change when you change the fork. There is probably no
way to know for sure if it going to help until you try it.
If you feel lucky put your money down and roll the dice with the
fork.
As far as carbon bars go I have this thought...
Climb some steep climbs and put some stress fractures in the carbon
bars. Get over the top and descend. Build up some good speed - hit a
bump and break the handlebars. Now I think about trying to steer with
my wife on back while traveling at top speed. Then I think about
trying to explain what happened to the kids - if I can. Then I think
it is best to go with more durable handlebars.
Your results may vary.
Old5ten
Probably right, but what I did not factor in was the performance
characteristics of the fork.
It is rock solid in
a descending corner, but not like a brick wall, more like a well
suspended muscle car of the 70's. .... Solid, but really smooth.
As for the bars I'm with Jake. This is similar to putting Titanium
chain ring bolts on to save weight, and if you care that much about
weight you should have just jumped off the cliff and gotten a Calfee
all carbon two seater.
Old5ten
WMdeR
> I know carbon is lighter but would we see other benefits
> going to carbon fork and/or handlebars? Input appreciated.
(Kestrel, Zipp, Modolo) on my Calfee (single). The weight loss is
negligible--on the order of 20g a bar if you're riding a light
aluminum bar to begin with. I never had one fail (crashed on a
Kestrel EMS bar in 2006, though, and decided to retire it. No visible
damage to the bar, and I hit it hard enough to break an Ergo lever and
ground the other lever down a good bit). They tend to be built not
for ultimate light weight, but for increased stiffness in the hands of
powerful sprinters.
My conclusion: carbon-fiber handlebars are stiff. Really stiff.
Unfortunately, too stiff for long-distance comfort given my low power
output and eleven stone. I went back to lightweight aluminum
handlebars and noticed an immediate improvement in my impression of
how the bike handled on rough roads and less hand distress in the
second century of a long day. It is going to transmit more road shock
(though less vibration) to your hands and arms.
However, I know you two put out a fair bit of power, so if you don't
like the way the handlebar/stem flexes under your combined power when
sprinting or climbing out of the saddle, then it may be worthwhile.
Fork: Assuming you can get a fork with the same geometry, it is an
even trade in terms of handling, a different ride feel, and you can
lose a bit of weight of of your tandem with respect to the stock steel
fork. Is losing a pound on a 30+pound machine with 275lb+ of riders
worth the effort/money?
I'd suggest it is worthwhile only if you're correcting some deficiency
in the way your machine handles, or if the current fork is damaged or
missing a vital fitting.
Enjoy your rides this winter!
Best Regards,
Will
William M. deRosset
RUSA 2401
Fort Collins, CO
Ian Boehm
>> Input appreciated.
>
>
>> ...Nashbar cross carbon fork. It has mounts for a disk brake,
>> which I use. The fork is just as if not heavier then my
>> quality steel forks. I'd never trust anything less beefy
>> then that hunk of plastic
>
> Apparently your trust is justified...from:
>
> http://www.nashbar.com/bikes/Product_10053_10052_175019_-1_201511_10000_
> 201514
Hmmmm
Lobbed into the above site and saw a very familiar fork as I'd bought
one the same or VERY similar from a supplier in the UK. Mine was scored
to put on my recumbent [long story] but now graces my daughter's MTB.
Mine came unbranded but I've seen an identical one in a LBS (forget
brand name) but both have an identical sticker which says:
***************
"WARNING!
This fork is only to be used for off-road riding & guaranteed for 2
years from purchasing day. For more information please contact your dealer."
**************
I'm not sure what the implications of the above are or if the Nashbar
one is adorned with this sticker.
Surely off-road riding is a more testing end use than road duty. Perhaps
the legal advisors thought that there might be fewer casualties from a
failure off-road. My bet is that the dealers referred to would have no
more idea.
The daughter likes it (road only) as it significantly lightened the bike.
Dunno if I'd use it on a tandem.
--
Cheers
__o
_`\<,
...(*)/(*)
Ian Boehm
--
Cheers
__o
_`\<,
...(*)/(*)
Ian Boehm
Orin
There are some that say the Nashbar fork is the same. I wouldn't
know.
Anyway, the Winwood Muddy Disc Cross is the _only_ Winwood fork that
_doesn't_ have the following disclaimer: "This fork is not designed
nor tested for tandem use" and in fact Calfee list it as a fork to use
with their carbon fiber tandems, along with forks from Wound Up and
Alpha Q.
Orin.
Monkey Boy
Thanks for the input. Weight was never the issue. I tore my rotator
cuff several years ago and vibration coupled with the extra upper body
work as captain on a tandem sometimes bothers me. I was curious if
carbon would have less vibration.
I'm not changing the fork.
I have considered using a moustache bar & bar end shifters like I have
on my cyclocross/commuting/city bike.
I'm also considering Grand Bois or Jack Brown tires.
Any thoughts?
Bill Gobie
suspension if your frame has the clearance. Be sure to use an
appropriate pressure, i.e., not rock hard. See Berto's chart for a
good starting point:
http://sooper-genius.blogspot.com/2007/06/optimum-tire-pressure-35mm-tires.html
I can send you a formula if your tire width isn't on the graph.
Another option is a Pantour suspension hub. We have one on the front
of our Counterpoint tandem. The stoker sits over the front wheel in a
recumbent position on this bike. The hub makes a huge improvement in
the stoker's comfort. I have also tried a Pantour hub front wheel on
a Bacchetta recumbent. It completely transformed the ride. This was
with a super uncomfortable 650C Bontrager RaceLite HardCase "tough
enough to break your teeth" tire. If you also want a generator hub
then you have a tough decision.
http://www.pantourhub.com/products.html
Bill
PCH Rando
to the vibration from the road at around 300k. I switched from 28
Continental Gatorskins to 30 Grand Bois and finished PBP without
significant hand issues.
I was amazed at how much a difference the tires made.
A lot of riders who are more concerned about fashion rather than
function will tell you that the wider tires are slower. Try them and
then form your own opinion.
My opinion is that the wider tires are plenty fast and do a great job
in reducing vibration. It is a relatively cheap and easy fix.
Been there, done that, worked for me, maybe it will work for you.
WMdeR
> on my cyclocross/commuting/city bike.
> I'm also considering Grand Bois or Jack Brown tires.
> Any thoughts?
Does road vibration (the buzz from the embedded aggregate), or road
shock (bumps, potholes, expansion cracks, chipseal, etc) bother your
rotator cuff more? A carbon bar will cut vibration (the three I used
all felt "quiet" on a smooth, freshly paved road), but will pass more
shock, as they were more stiff than an aluminum bar.
However, bigger tires are easily the most cost-effective way to reduce
the road shock and vibration on a bike. I'd suggest trying the
biggest nice tires you can fit before going to more heroic measures
like suspension seatposts, stems, hubs, etc.
I've no experience with the Jack Brown tires. The Roly Poly's use the
same casing and design, but are narrower. They were round,
comfortable, tough, flat-resistant, long-wearing, cornered well, and
were decidedly slower than the narrower racing clinchers they
replaced. I switched back to narrow (Vittoria 24mm) tires until the
GB and Challenge P-R tires became available for my randonneuring
single.
The Grand Bois Cyprès (30-622) had some QC bobbles when they first
came out, reportedly since fixed. They are nice-riding tires and are
quite comfortable for their size and weight. They corner
exceptionally well and are reasonably durable. They're a good option
if you don't ride off pavement a lot. I tore two casings on gravel
roads.
Another tire to consider is the Panaracer Pasela. The 32-622 are
about the same width when inflated as the 30-622 Grand Bois. Without
the Tourguard belt, the Pasela rides similarly to the GB once they
wear in a bit, though it doesn't corner quite as nicely, and is not
available in kevlar bead (without the tourguard belt). The Paselas
are also readily available in 37-622 and 35-622 if your tandem can fit
them.
The key to comfort with these wider tires is to adjust the tire
inflation pressure to match the load and tire width. Others have
posted a link to Frank B's chart, which seems to provide reasonable
starting points for pressures in my load range.
I use the Challenge Paris-Roubaix 28mm tire for events, but the total
weight is under 175lb including the bike and my luggage. I use Pasela
32-622 or Grand Bois 30-622's in the winter, as they are more flat-
resistant than the Challenge tires.
If I were equipping a tandem, I'd seek wider tires than 30mm to get
the inflation pressures down into the 80psi range. Looking at Frank
B's chart:
http://www.vintagebicyclepress.com/images/TireDrop.pdf
I'd say 35mm tires would be about right for that pressure on a tandem--
if they fit! The 35mm Paselas (without tourguard) reportedly
performed about as well as an average 23-622 racing tire in Jan H.'s
roll-down tests.
Good luck.
Best Regards,
Will
William M. deRosset
RUSA 2401
Fort Collins, CO
Monkey Boy
Thanks for the info. Vibration, more than pounding from a hole or
bump, causes my shoulder problems. It doesn't happen all the time but
if we're going to expand riding the tandem into the 400K-600K range
it's something I need to address.
Our tandem has lots of room for wider tires than the 28mm Continental
Ultra GatorSkin that we currently use. I'll consider the 30mm Grand
Bois or 32mmPasela. Maybe even the 35mm Pasela.
Val
DrCodfish
I've settled on the JB's on my single bike. The best riding tires
were the Gran Bois hands down, but they were just not tough enough for
my riding. I ride a lot of country and farm roads, and I'm a big
load, probably pushing 250#+ total weight. The Contis were the most
durable, but the harshest ride. The Paselas were more comfortable
but, a little more prone to flats. The JB's at about 70psi are the
sweet spot for me. At 33mm they fit my bike, give a ride nearly as
comfortable as GB's but are very flat resistant, even the lighter wt
JB greens. We have the Paselas on the tandem, if it could fit wider
tires, I'd have the JB's on there.
If I am not mistaken the Paselas, GB's, and the JB's all are made by
the same manufacturer.
Yr Pal Dr C
WillemJ
bikes, also on gravel roads, I think the simple truth is the wider the
better. Quality tyres with flexible casings make a difference, but the
effect of tyre width is far greater. This also seems to be borne out
by Jan Heine's recent tests in Bicycle Quaterly. Moderately inflated
wide tyres are not only far more comfortable, but even on tarmac they
are faster. The smoothest tyre I have ever riddden was the 50 mm
Schwalbe Big Apple. If that is too much for your taste or if you do
not have the clearance, a 37 mm Pasela may be a good choice. Their
drawback for you is a relatively course tread pattern. I have the
26x1.75 for lightly loaded fast trips on my tourer, and on smooth
surfaces I can feel a slight vibration from the tread pattern. You
would not have this with a pure slick such as a Schwalbe Kojak.
Unfortuntely the widest they do in etrto 622 is 35 mm (in 559 they do
a full 50mm).
Willem
VinnieS
Up carbon fork several years ago. Knocked off about 1.5 pounds. What I
appreciated even more was improved handling. I believe the Wound-up
fork has 5mm less trail. Made the tandem quicker handling. We have
been riding a tandem for over 20 years. I like a tandem that handles
closer to my singles. Our first tandem was Lippy. Really noticed how
sluggish the Meridian felt when we first got it.
Carbon bars do not provide as much of a weight savings. I have them on
a couple of my single bikes but still an alloy on the tandem. Carbon
doesn't fatigue like aluminum. I wouldn't avoid carbon due to fear of
failure. In fact, carbon bars may be less likely to fail. I've had 3
single bike steel frames fail. My highest mileage single bike now is a
carbon Look.