off center rims (hype or helpful)?
LF
building up a rear wheel with a 7-speed rear freewheel or cassette.
In theory, OC rims make for a stronger wheel, with less dish.
Detractors note: 1) the lack of eyelettes on OC rims and 2) some
report that at least some Synergy rims (a 36-hole eyeletted OC rim I'm
considering <http://tinyurl.com/yf6ophk>) can have too small a
diameter for many 700C tires.
For a strong and durable rear wheel, on a lightweight steel
transportation bike, with 25cm to 28cm tires, what currently available
rims should I consider?
Thanks much,
Larry
thirty-six
> I'm wondering about the utility of off-center rims. I'm thinking of
> building up a rear wheel with a 7-speed rear freewheel or cassette.
> In theory, OC rims make for a stronger wheel, with less dish.
Will they be best suited to your tyre choice?
> Detractors note: 1) the lack of eyelettes on OC rims
lets you examine around the nipple holes for cracks and you either
reject the rim or burnish them away if they are small enough.
Use fibre washers for nipple support if the rim is not dimpled or
otherwise supplied with washers to provide a good seat for the nipple
head.
> and 2) some
> report that at least some Synergy rims (a 36-hole eyeletted OC rim I'm
> considering <http://tinyurl.com/yf6ophk>) can have too small a
> diameter for many 700C tires.
Choose your tyre, then your rim.
>
> For a strong and durable rear wheel, on a lightweight steel
> transportation bike, with 25cm to 28cm tires, what currently available
> rims should I consider?
I think your dimensions should be in millimetres. If this is true,
which I suspect, then you should probably be thinking of something
wider if you are "transporting". The minimum width for a care free
rim is around 22mm over the outside walls, this is usually entirely
suitable for a tyre from 25mm to 32mm. Depending on your roads, speed
and load, you may want a tyre anywhere between 25mm to 38mm. The
advantage of a wider tyre is that you run it at a lower pressure,
giving better cornering power and a more comfortable ride with less
rider fatigue. Only experience will tell you which is your preferred
level of comfort.
LF
> > For a strong and durable rear wheel, on a lightweight steel
> > transportation bike, with 25cm to 28cm tires, what currently available
> > rims should I consider?\
>
Nov 22, 4:10 pm, thirty-six <thirty-...@live.co.uk> replied : <snip>
I think your dimensions should be in millimetres.
Yes, I stand corrected.
If this is true <snip>
> Only experience will tell you which is your preferred
> level of comfort.
I like 25mm -28mm width tires (tyres).
thanks.
Best,
Larry
landotter
Sun CR18, Salsa Delgado, and VO PBP come to mind. The VOs can come
laced with DT spokes to a 105 hub for $112 or you can build them
yourself.
For durability, running a 28-32 mm tire will make a bigger different
than rim brand.
dusto...@mac.com
Velocity Aerohead OC's have done very well for me.
They are pretty light; you might want to consider heavier rims if
available, but the only problem I've had is one machined-sidewall rim
cracking out, sidewall from rim bed, pretty "early", probably due to
"too much machining", as the other two rims have covered more miles
with no problem.
A non-machined model is offered, I'd go with those just to prolong
service life.
Tire fit with 25 Conti's is fine. 23mm Michelin, Vredestein, possibly
Hutchinson also very good. None "too loose", none too tight.
I rode these "well over 200lbs" in 32 and 36h, they stayed tight and
true very well on 9sp, 130mm OLD hubs-- if you're going 7sp freewheel,
your hub might be 126mm and that would make a stronger-yet rear wheel.
No eyelets doesn't seem to be an issue. Not discounting an expert
wheel build by Bobby of Bobby's Bikes here in Austin. --D-y
Qui si parla Campagnolo
Not hype but a great idea. Even the ones DESIGNED to have no eyelets
work fine, like the Aerohead OC. But that's a pretty light rim. I
would look at this one-
http://www.velocityusa.com/default.asp?contentID=591
Great rim with the understanding that with a 7s rear wheel the L/R
tension will almost be equal. They work just fine with tires in the
23-32 range.
Peter Howard
"Qui si parla Campagnolo" <pe...@vecchios.com> wrote in message
news:baef44e3-05ce-4bd8...@x25g2000prf.googlegroups.com...
http://www.velocityusa.com/default.asp?contentID=591
My input
xxxxxxxx
(something weird when replying in Outhouse Express to posts originating in
Google groups. Doesn't put in the quote >> thingys)
Anyway, agree that Velocity Synergy OC with eyelets is a great rim. Built three
wheelsets so far using these, one in 26", two 700c and never noticed any fit
troubles with Vittoria, Schwalbe, Kenda or Maxxis tyres. With modern rims and
spokes there's nothing actually WRONG with considerable dish and consequent
difference in left/right spoke tension but it's confidence-inspiring to build
on an OC rim and measure less tnan 10% difference. They're pretty much my rim of
choice these days. And they look nice too.
PH
N8N
Unfortunately, the VO rear wheels haven't been available for a while.
I bought one of the dynohub fronts, but ended up having a LBS make me
a matching rear wheel as I was tired of waiting for VO to get them
back in stock, if they ever will :(
nate
Tom Sherman °_°
>
> [...]
> (something weird when replying in Outhouse Express to posts originating
There are better alternatives, some of which are free, e.g.
<http://www.mozillamessaging.com/en-US/>.
--
Tom Sherman - 42.435731,-83.985007
I am a vehicular cyclist.
landotter
CR18 or PBP? They just got some pallets in that include the 105/PBP
wheels according to the blog.
bfd
nipple. My rear wheel had a 32h Mavic Open Pro rim, DT db spokes
(14/15 or 2.0/1.8) and Shimano DA 9 rear hub. I had the wheel about
12 year and estimated it had somewhere between 20-25K miles on it. I
had a spare Mavic MA2 rim hanging in my garage and am having the wheel
rebuilt with it.
Similarly, I also have a wheel build with 32h Ritchey OCR rim, DT db
spokes and Chorus rear hub. I had maybe 1000 miles on the rear wheel
and found the Ritchey rim cracked around the right/drive side spoke
hole. Needless to say, I'm very disappointed with the Ritchey rim (as
well as the built as I think it might have been over tensioned.
Sigh. I'm thinking about having the chorus rear wheel rebuild. I have
another Mavic MA2 rim, but was advised against using it with Campy
Chorus rear hub because of the offset of the hub. Therefore, I'm
thinking of using a Mavic Open Pro rim. Good Luck!
dusto...@mac.com
> Similarly, I also have a wheel build with 32h Ritchey OCR rim, DT db
> spokes and Chorus rear hub. I had maybe 1000 miles on the rear wheel
> and found the Ritchey rim cracked around the right/drive side spoke
> hole. Needless to say, I'm very disappointed with the Ritchey rim (as
> well as the built as I think it might have been over tensioned.
> Sigh. I'm thinking about having the chorus rear wheel rebuild. I have
> another Mavic MA2 rim, but was advised against using it with Campy
> Chorus rear hub because of the offset of the hub. Therefore, I'm
> thinking of using a Mavic Open Pro rim. Good Luck!
Suggestion: Query the group, especially the shop owners IRT the
longevity and/or general "goodness" of those rims.
If they get a passing grade, and if you can get another Ritchey OCR
rim cheap or reasonable, have it rebuilt with one of those same items
by someone who has and knows how to use and uses a tensionometer <g>.
Save yourself the cost of a set of spokes. Maybe new nipples, brass,
if the old ones were alloy.
--D-y
bfd
wrote:
Thanks. I thought of that, but it appears the Ritchey OCR rim has been
discontinued and no longer available. Having said that, maybe one of
the shop owners here may have a 32h Ritchey OCR rim laying around for
me to consider. Alternatively, since I do have a couple of rims
hanging in my garage, one is an Mavic MA2 and the other is an Open
Pro, I may just use one of those, although because of the offset of
Campy rear hubs (its a Chorus from around 2001 with the oversized
axle), I've been advised NOT to use the MA2.
dusto...@mac.com
> Thanks. I thought of that, but it appears the Ritchey OCR rim has been
> discontinued and no longer available.
There's a list of rims here, where you might find a rim that uses the
same spoke lengths as the Ritchey:
<http://www.sheldonbrown.com/rinard/spocalc.htm>
Yes, I've seen advice to not use the MA2 on rear wheels with large
offset (assuming 130mm OLD or more).
I wouldn't know from trying it myself but I offered up the Velocity
Aerohead OC partly as a testimony that OC
design apparently allows light rims (425g approx. for the A-head OC on
Weight Weenies) to stand up under heavy riders,
including in 32 spoke configuration. --D-y
AMuzi
>> Thanks. I thought of that, but it appears the Ritchey OCR rim has been
>> discontinued and no longer available.
dusto...@mac.com wrote:
> There's a list of rims here, where you might find a rim that uses the
> same spoke lengths as the Ritchey:
>
> <http://www.sheldonbrown.com/rinard/spocalc.htm>
>
> Yes, I've seen advice to not use the MA2 on rear wheels with large
> offset (assuming 130mm OLD or more).
> I wouldn't know from trying it myself but I offered up the Velocity
> Aerohead OC partly as a testimony that OC
> design apparently allows light rims (425g approx. for the A-head OC on
> Weight Weenies) to stand up under heavy riders,
> including in 32 spoke configuration. --D-y
Where values for 'heavy' fall below about 200lbs. A bit
higher with a 25mm+ tire. Otherwise use a Synergy OC.
We like Aerohead OC; round, reliable and only 400g but a bit
light for 'big guys'.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
Chalo
>
> [re: Aerohead OC]
> Where values for 'heavy' fall below about 200lbs. A bit
> higher with a 25mm+ tire. Otherwise use a Synergy OC.
>
> We like Aerohead OC; round, reliable and only 400g but a bit
> light for 'big guys'.
I want to have access to a Chukker OC. That is something tandemists
and I would be able to use with confidence, whether for dished
cassette rear wheels or dished disc fronts.
Velocity rims, despite all their details that leave room for
improvement, are amazingly flat, round and uniform. They are a
pleasure to build with. If all rims were so consistent, wheelbuilding
might not have such a reputation for being a black art.
Chalo
AMuzi
>> [re: Aerohead OC]
>> Where values for 'heavy' fall below about 200lbs. A bit
>> higher with a 25mm+ tire. Otherwise use a Synergy OC.
>> We like Aerohead OC; round, reliable and only 400g but a bit
>> light for 'big guys'.
Chalo wrote:
> I want to have access to a Chukker OC. That is something tandemists
> and I would be able to use with confidence, whether for dished
> cassette rear wheels or dished disc fronts.
>
> Velocity rims, despite all their details that leave room for
> improvement, are amazingly flat, round and uniform. They are a
> pleasure to build with. If all rims were so consistent, wheelbuilding
> might not have such a reputation for being a black art.
We're using Chukkers including 48h on tandems since they
came out. So far very impressive but I do not believe they
are offered in OC format.
thirty-six
>
> > For a strong and durable rear wheel, on a lightweight steel
> > transportation bike, with 25cm to 28cm tires, what currently available
> > rims should I consider?
>
> I too use 25mm wide tires and recently had a rear rim crack around the
> nipple.
Overtensioned spokes.
> My rear wheel had a 32h Mavic Open Pro rim, DT db spokes
> (14/15 or 2.0/1.8) and Shimano DA 9 rear hub. I had the wheel about
> 12 year and estimated it had somewhere between 20-25K miles on it. I
> had a spare Mavic MA2 rim hanging in my garage and am having the wheel
> rebuilt with it.
A robust enough rim when put into goosd hands.
>
> Similarly, I also have a wheel build with 32h Ritchey OCR rim, DT db
> spokes and Chorus rear hub. I had maybe 1000 miles on the rear wheel
> and found the Ritchey rim cracked around the right/drive side spoke
> hole.
Poor build, including overtensioned spokes.
> Needless to say, I'm very disappointed with the Ritchey rim (as
> well as the built as I think it might have been over tensioned.
> Sigh. I'm thinking about having the chorus rear wheel rebuild. I have
> another Mavic MA2 rim, but was advised against using it with Campy
> Chorus rear hub because of the offset of the hub. Therefore, I'm
> thinking of using a Mavic Open Pro rim. Good Luck!
Tat may compensate for a poor build if you are lucky.
thirty-six
Hoogywotsits dont' help wheelbuilding.
thirty-six
Choose something of 450-480g in a wired-on rim for reliability
(without too much dead load).
Qui si parla Campagnolo
Use the MA-2, no reason not to on a 'Campagnolo' hubs. The 'offset' is
only 1mm farther to the left when compared to a shimano hub. I have
build more than a few wheels using Campagnolo hubs on a variety of rims
(including MA2 and MA40) w/o any issues.
Qui si parla Campagnolo
Yep, knowing the true tension doesn't help wheelbuilders at all.
Torque wrenches don't help car mechanics either. Scales don't help
chemists, measuring tools are silly, what are you thinking.
dusto...@mac.com
> Hoogywotsits dont' help wheelbuilding.
Never tried one of those.
IRT to tensionometers, if that's the "H-s" reference, didn't you just
bring up "over-tensioned"?
Maybe that was someone else...
--D-y
bfd
wrote:
Thanks. On the wheel with the Chorus rear hub, DT db spokes and
Ritchey OCR rim that MAYBE had 1000 miles on it, I agree, it was
probably incorrectly built and resulted in the rim cracking around the
spoke hole. Jobst may argue that it was the anodizing (black rim) or
maybe even lack of eyelets, but I'm agreeing with you guys that it was
overtensioned.
However, on my other rear wheel where the rim cracked, it had a
Shimano DA 7700 rear hub DT db spokes and Mavic Open Pro rim, the
drive side spoke was pulling thru the rim. Since that wheel was over
12 years old and had between 20-25K miles on it, I'm thinking the
anodizing caused the rim to crack. Note, when I bought the wheel, it
was a pre-build from a shop. I had the shop initially true, dish and
stress relieve the wheel. NEVER had a problem with it! It was a well
built wheel. Good Luck!
bfd
wrote:
This is interesting. On another forum, a *well-known* internet
wheelbuilder named Peter White, claims just the opposite:
I wrote:
> Are you telling me that the 1mm or so offset of the Campy rear hub is
> going to make that much of a difference that I can't use a Mavic MA2
> or Open Pro rim?
Peter responded:
<<Of course you can use whatever you like. I recommend against it. The
reason I recommend against it is the extraordinary number of cracked
right rear spoke holes in Open Pro/Reflex/Open 4, MA-40/MA-2, and
various Campy rims I've seen since the introduction of Campy's eight
speed cassette hub. In my opinion, it's a really really really really
really really really really really really really really bad
combination. While none of those rims is a great choice for a heavy
rider with a Shimano hub, the differrence in the frequency of rim
cracks between Campy and Shimano hubbed rear wheels is dramatic. If
you keep the right side tension low enough to prevent the cracking,
the left side tension is way too low, and you end up with lots of
broken left side spokes, unless you're a featherweight, or typical Cat
1 racer type. And even those guys don't often get high mileage out of
them. >>
thirty-six
Ignore it. Use 15swg spokes (or 14) and remove the spoke bows and
you will not need to take the spoke tension so high. Use some wax or
boiled linseed to secure the nipples.
thirty-six
> > Hoogywotsits dont' help wheelbuilding.
>
> Yep, knowing the true tension doesn't help wheelbuilders at all.
> Torque wrenches don't help car mechanics either. Scales don't help
> chemists, measuring tools are silly, what are you thinking.
A hoogywotsit wont give you true tension only an indication. Better
to compare builds by rim displacement.
thirty-six
If you build with appropriate components without bows in the spokes
and to a good wheel response, the spokes will not be so tight as to
cause pull through or fatigue.
dusto...@mac.com
I was thinking of published info from manufacturers IRT tension
measured with a tensionometer. Which is comparing apples to apples,
when you measure tension with a calibrated instrument, with the same
method ("systematic procedure"). "Not perfect", but the best you can
do.
Sorry, 36, my dad started out as a toolmaker's apprentice, and had a
long career that included supervising the manufacture of millions and
millions of "screw fasteners". He had professional, fraternal respect
for able mechanics and machine operators. And he bought me a torque
wrench to work on my bike with-- because, as he explained, in spite of
materials differences, manufacturing tolerances, lubrication, which
way the wind is coming from or what you had for lunch, "that's the
best you can do". IOW, it's best to use your experience *and* a
measuring tool in this imperfect world.
--D-y
Chalo
>
> thirty-six wrote:
> >
> > Hoogywotsits dont' help wheelbuilding.
>
> Never tried one of those.
>
> IRT to tensionometers, if that's the "H-s" reference, didn't you just
> bring up "over-tensioned"?
>
> Maybe that was someone else...
Homecheese insists that slack spokes are preferable as long as you
bend them *just so*.
The rest of us should consider using adequate tension, and letting the
tension (predictably) dictate the shape of the spokes.
Chalo
thirty-six
The appropriate method also tests the rim and is relevant to load
carried. This is attained using a test load and either checking the
length of the arc which is pushed inward, by the number of spokes
exhibiting reduced tension, or checking for rim displacement at the
wheel's base, which could be with a depth gauge or the point at which
a spoke becomes loose. This is not a diificult system to set up, it's
benefits are that wheel response can be compared between different
component choices and adjusted appropriately for different load
requirements.
dusto...@mac.com
I feel like someone just tried to baffle me with bullshit. First, a
pretty simple, straightforward measurement tool is derided, then an
elaborate test rig that measures (I think) three different parameters
is postulated.
Nothing like measuring for yourself, of course, but we have a couple
of shop owners here sharing experience via recommendations that name
certain rims as being suitable for a given use.
Following, a pro buildup with measured tension, per manufacturer specs
(tempered by "field results", as I understand Mavic's recommended
specs might be a little high <g>) would seem to be a straightforward
program. --D-y
Jobst Brandt
>>>>>> Hoogywotsits dont' help wheelbuilding.
>>>>> IRT to tensionometers, if that's the "H-s" reference, didn't you
>>>>> just bring up "over-tensioned"?
>>>>> Maybe that was someone else...
>>>> If you build with appropriate components without bows in the
>>>> spokes and to a good wheel response, the spokes will not be so
>>>> tight as to cause pull through or fatigue.
>>> I was thinking of published info from manufacturers IRT tension
>>> measured with a tensionometer. Which is comparing apples to
>>> apples, when you measure tension with a calibrated instrument,
>>> with the same method ("systematic procedure"). "Not perfect", but
>>> the best you can do.
>>> Sorry, 36, my dad started out as a toolmaker's apprentice, and had
>>> a long career that included supervising the manufacture of
>>> millions and millions of "screw fasteners". He had professional,
>>> fraternal respect for able mechanics and machine operators. And
>>> he bought me a torque wrench to work on my bike with-- because, as
>>> he explained, in spite of materials differences, manufacturing
>>> tolerances, lubrication, which way the wind is coming from or what
>>> you had for lunch, "that's the best you can do". IOW, it's best
>>> to use your experience *and* a measuring tool in this imperfect
>>> world.
>> The appropriate method also tests the rim and is relevant to load
>> carried. This is attained using a test load and either checking
>> the length of the arc which is pushed inward, by the number of
>> spokes exhibiting reduced tension, or checking for rim
>> displacement at the wheel's base, which could be with a depth gauge
>> or the point at which a spoke becomes loose. This is not a
>> diificult system to set up, it's benefits are that wheel response
>> can be compared between different component choices and adjusted
>> appropriately for different load requirements.
> I feel like someone just tried to baffle me with bullshit. First, a
> pretty simple, straightforward measurement tool is derided, then an
> elaborate test rig that measures (I think) three different
> parameters is postulated.
> Nothing like measuring for yourself, of course, but we have a couple
> of shop owners here sharing experience via recommendations that name
> certain rims as being suitable for a given use.
> Following, a pro buildup with measured tension, per manufacturer
> specs (tempered by "field results", as I understand Mavic's
> recommended specs might be a little high <g>) would seem to be a
> straightforward program.
I think I gave a reasonably accurate way of testing maimum spoke
tension and show an insrument fo measuring that tension.
Jobst Brandt
thirty-six
A set single test load may be used and the spokes adjusted so this
load makes one loose. The load may be applied using a lever, fulcrum
and the most complicated bit of kit, the wheelbuilders mass. If
you've a solid building and truing jig this is easily done. Otherwise
you need to fabrcate something up. I used a steel strap hooked under
the tail stock of a bench vice and used the vice jaws as the fulcrum.
If I'm building more than a pair of rims, I get a feel for them and
can judge pretty well without necessarily resorting to static
testing. If I have time, I usually put the wheels on one of my own
bikes and do a dynamic test. If the rider is significantly lighter
than me, I will knock off up to 1/2 turn from my ideal setting as
tested over cobbles. The dynamic testing and adjusting can take a
little time if I decide I like the wheels.
>
> Nothing like measuring for yourself, of course, but we have a couple
> of shop owners here sharing experience via recommendations that name
> certain rims as being suitable for a given use.
>
> Following, a pro buildup with measured tension, per manufacturer specs
> (tempered by "field results", as I understand Mavic's recommended
> specs might be a little high <g>) would seem to be a straightforward
> program. --D-y
If you use exactly the same build detail and the rim carience is
within about 4%
landotter
> AMuzi wrote:
>
> > [re: Aerohead OC]
> > Where values for 'heavy' fall below about 200lbs. A bit
> > higher with a 25mm+ tire. Otherwise use a Synergy OC.
>
> > We like Aerohead OC; round, reliable and only 400g but a bit
> > light for 'big guys'.
>
> I want to have access to a Chukker OC. That is something tandemists
> and I would be able to use with confidence, whether for dished
> cassette rear wheels or dished disc fronts.
Heh, the Chukker 650g mass should be a potent ingredient in a tough
wheel, regardless of dish. With a NDS half radial built, it might even
satisfy a Chalo. ;-)
Qui si parla Campagnolo
He had some sort of hardon for Campagnolo hubs. I have build hundreds
of OpenPro/Open4 rears with Campagnolo cassette hubs and dozens
probably of MA-2 w/o any problem whatsoever. Proper right side tension
(100 kgf), makes for sufficient left side tension. Wheel stays true,
spokes don't break. I think the BIG issue is hard anodized rims which
DO crack more often becaue of the micro cracks created by installing
the eyelets after hard anodizing. I try to not use those. Mavic Reflex
rims were of a soft aluminum that mavic recognized, why they were only
around 1 year. MA-3s as well. OpenSport work fine. If he sees a lot
more cracks in Campagnolo hubbed wheels than shimano, then it's his
wheelbuilder, not the hub. He also has some sort of huge problem with
DT since the AWFUL change in their spoke bend a few years ago. Right
up there with other worldwide problems, in his eyes. BUT I have used
DT exclusively since this 'change', have built probably 2500-3000
wheels
since with no problems. One thing that is a given in retail, if a
customer is unhappy, you hear about it.
thirty-six
If you dont form the spokes at the interlace you require greater
tension on the spokes in an attempt to stabilise the wheel. This can
be in excess of what the rim can withstand and desroy the rim within a
couple of thousand miles. The 'solution' to use a heavier rim is an
error itself as it results in a wheel with too much axial rigidity for
smooth running. The 'solution' to this is a bigger tyre, which wont
fit the frame. The 'solution' to this is longer chainstays which
results in a long wheelbase bicycle which wont fit in the cupboard.
The 'solution' to this is to build a bigger cupboard. Easy really.
thirty-six
> He had some sort of hardon for Campagnolo hubs. I have build hundreds
> of OpenPro/Open4 rears with Campagnolo cassette hubs and dozens
> probably of MA-2 w/o any problem whatsoever. Proper right side tension
> (100 kgf), makes for sufficient left side tension. Wheel stays true,
> spokes don't break. I think the BIG issue is hard anodized rims which
> DO crack more often becaue of the micro cracks created by installing
> the eyelets after hard anodizing.
Do you mean surface cracking or splitting, and for ferruled rims?
dusto...@mac.com
wrote:
(trimmed and snipped a little):
> I have build hundreds
> of OpenPro/Open4 rears with Campagnolo cassette hubs and dozens
> probably of MA-2 w/o any problem whatsoever. Proper right side tension
> (100 kgf), makes for sufficient left side tension. Wheel stays true,
> spokes don't break. I think the BIG issue is hard anodized rims which
> DO crack more often becaue of the micro cracks created by installing
> the eyelets after hard anodizing. I try to not use those.
> If he sees a lot
> more cracks in Campagnolo hubbed wheels than shimano, then it's his
> wheelbuilder, not the hub. He also has some sort of huge problem with
> DT since the AWFUL change in their spoke bend a few years ago. Right
> up there with other worldwide problems, in his eyes. BUT I have used
> DT exclusively since this 'change', have built probably 2500-3000
> wheels
> since with no problems. One thing that is a given in retail, if a
> customer is unhappy, you hear about it.
Not much for mystique there, are you, Mr. Chisholm? <g>
Grazie tanto, Signor Vecchio.
--D-y
bfd
Unfortunately, Peter White is not the only one who doesn't like
Campagnolo hubs. Piaw Na, an Engineer, and his friend Pardo (of
Pardo's broken bike part fame), tested several hubs and concluded that
Campy hubs were the weakest of the ones tested:
http://piaw.blogspot.com/2009/07/hubs.html
They claim: "if you're running Campy wheels, you have to run OC rims
to have any wheel strength at all." What's interesting is Campy hubs
are used by thousands, if not tens of thousands of people and if the
hubs were that weak, you would hear horror stories of broken hubs
causing death and destruction. For whatever reason, you don't. I
believe the oversized axles on the Campy hubs (1999-current) solve any
problem with axles breaking. And, as you suggested, if the wheel is
*well-built* and NOT over-tensioned, you don't have broken spoke
problems. Of course, using an OC type rim helps too. Good Luck!
thirty-six
Who says "I consider use of loctite/spoke-prep bad practice" and so
overstresses hub and rim to prevent nipple unwinding and reduce active
spoke bending at the flange juncture. Even Campag hubs are over
engineered for their purposes, as they always have been. If you get
failures with Campag' hubs you are doing it wrong.
It should be remembered that the left and right side of the wheel both
play their part in restraining the lateral deviation of a rim no
matter which side the force is placed.
dusto...@mac.com
You don't have to capitalize the first letter in doctor, lawyer,
garbageman, etc. etc. when the job title in the above and similar
sentence positions.
Doctors, lawyers, engineers, and garbagemen are all a dime a dozen and
they all are just people, nothing special in a broader frame of
reference/no reverence. Just people = subject to all frailties incl.
error and appealing to a sense of mystique in order to build a
customer base.
Lemme go look at my list of Rhetorical Appeals and see where this
Piaw, Pard, and Maybe stuff fits. "Impending danger", off the top of
my head.
"Possessed of superior knowledge", etc. etc. Back later...
Dang, I can't quite put my finger on it... there was a custom frame
maker, might have had two main "operators" (yup, he said operators),
one of whom wrote into one of the paper media, 'way back in the late
70's, going on and on about magical properties of Reynolds 531 tubing.
And manganese <g>. Don't want to name any names for fear of impugning
the unworthy, but I think they were located in Colorado. I'd love to
have that, and the rebuttal, to post here in rbt, it was a classic.
Anyone remember? --D-y
thirty-six
I think that went along the lines of, wind up the spokes until the
rim buckles and is unusable, then back it off a bit until the buckle
goes. Only thing is, it doesn't always disappear and the resulting
spoke tension will still likely be too high for good tracking and
comfortable running and still has a relatively high risk of buckling.
Chalo
>
> Proper right side tension
> (100 kgf), makes for sufficient left side tension. Wheel stays true,
> spokes don't break.
Do you use some kind of threadlocker? My experience with building and
repairing (mostly repairing) Mavic SUP-era rims has been so
consistently disappointing that I just avoid them. They build up
pretty, but they have trouble early and often.
Pinned Mavic rims have given me no trouble, but I avoid them too (on
the principle of "the way you do one thing reflects the way you do
everything").
Chalo
Chalo
>
> http://piaw.blogspot.com/2009/07/hubs.html
>
> They claim: "if you're running Campy wheels, you have to run OC rims
> to have any wheel strength at all." What's interesting is Campy hubs
> are used by thousands, if not tens of thousands of people and if the
> hubs were that weak, you would hear horror stories of broken hubs
> causing death and destruction. For whatever reason, you don't.
Most wheels are overbuilt for most riders and the purposes to which
they are put. This is normal and proper, but it does tend to allow
bad designs to hide among good ones because of overall low failure
rates.
Where the truth really comes out is in technically challenging
applications, like tandems, trials bikes, and downhill bikes, or bikes
for heavyweight riders. Tandemists and big riders like myself often
use fewer grams of wheel per kilogram of payload than even the most
fanatical weight weenie. When we can find something that performs
reliably, you know it's good.
I can't use a wheel that's dished as much as a 130mm 10-speed hub, let
alone a Campy hub that is dished even more than necessary for its
configuration. And yet with less offset, I can plausibly use a wheel
with the same rim, hub shell, and spoke count-- at least for a while.
I have gotten good long-term service from well-built and sturdy 32
spoke symmetrical wheels, but for an 8/9-speed cassette hub, I have to
use 48 spokes to get comparable reliability.
That implies to me that a Campy 10-speed wheel would have to be laced
with 52 or 56 spokes to offer the sort of reliability I'm accustomed
to. It would make much better sense to design in more right side
flange offset and fix the problem where it is most economical to do
so.
Chalo
Ozark Bicycle
That would be Jobst "the Great and Mighty" Brandt.
[...]
Ozark Bicycle
That *may* have been viable in the days of lightweight/flexible box
section rims such as the Mavic MA-2. And in the days before affordable
and reliable spoke tensiometers were available. And before rim makers
speced maximum spoke tensions.
Today, with modern rims, it *is* a recipe for an overtensioned rim
which will fail prematurely due to cracks around the spoke holes.
[...]
Chalo
>
> thirty-six wrote:
> >
> > I think that went along the lines of, wind up the spokes until the
> > rim buckles and is unusable, then back it off a bit until the buckle
> > goes.
>
> That *may* have been viable in the days of lightweight/flexible box
> section rims such as the Mavic MA-2. And in the days before affordable
> and reliable spoke tensiometers were available. And before rim makers
> speced maximum spoke tensions.
>
> Today, with modern rims, it *is* a recipe for an overtensioned rim
> which will fail prematurely due to cracks around the spoke holes.
Today's Mavic rims offer the unprecedented opportunity for cracked
spoke holes at normal, even specified tensions. This saves us a time-
consuming step in the product cycle between handing over too much
money and throwing the wasted rim in the trash.
Chalo
AMuzi
Although our preferred rim and spoke products differ, we
agree wholeheartedly with on your conclusion.
Despite much ranting about 'bad rims' or 'bad spokes' or
'inadequate hub spacing', a couple thousand satisfied
customer iterations on any given wheel means to us that the
product is good.
New wheel customers are tough critics. It works or it
doesn't and I sure hear when it's not right.
--
Andrew Muzi
<www.yellowjersey.org/>
Open every day since 1 April, 1971
thirty-six
<bicycleatel...@ozarkbicycleservice.com> wrote:
>
> > Who says "I consider use of loctite/spoke-prep bad practice" and so
> > overstresses hub and rim to prevent nipple unwinding
>
That would be Jobst "the Great all Tightly" Brandt.
It was posted by Piaw Na @ 9:56 PM Sunday, July 12, 2009 on "Piaw's
Blog" as "Bicycle Wheels: Loctite or Not"
http://piaw.blogspot.com/2009/07/bicycle-wheels-loctite-or-not.html
Not attributed to JB. So Piaw can claim it completely as his own
error.
Ozark Bicycle
Far be it from me to defend the current crop of Mavic aftermarket
rims. I find them over-priced, over-hyped and gimmicky. A 50% price
reduction is in order....
That said, if you follow Mavic's tension spec, cracks around the spoke
holes aren't a real problem. E.g., the spec for an Open Pro is
100kgf ; if you build them to that spec, no premature cracks (assuming
the rim is suitable for the load and duty cycle). You might have other
problems, such as keeping the NDS spokes from going slack - especially
if you follow Brandt's advice and eschew any type of threadlock on the
nipples (I use linseed oil with good results - YMMV).
Ozark Bicycle
> On 25 Nov, 22:58, Ozark Bicycle
>
> <bicycleatel...@ozarkbicycleservice.com> wrote:
>
> > > Who says "I consider use of loctite/spoke-prep bad practice" and so
> > > overstresses hub and rim to prevent nipple unwinding
>
> That would be Jobst "the Great all Tightly" Brandt.
What I wrote was: "That would be Jobst 'the Great and Mighty'
Brandt".
Great all Tightly is funny (and might refer to Brandt's bowels!), but
it is not what i wrote.
>
> It was posted by Piaw Na @ 9:56 PM Sunday, July 12, 2009 on "Piaw's
> Blog" as "Bicycle Wheels: Loctite or Not"http://piaw.blogspot.com/2009/07/bicycle-wheels-loctite-or-not.html
>
> Not attributed to JB. So Piaw can claim it completely as his own
> error.
It came from Brandt - part of the Commandments.
thirty-six
Not true. I used JB decribed method on a MA40 rimmed front wheel using
the recommended double butted DT spokes and it buckled severely when I
sprinted on it. Apparently to JB, bicycle wheels dont experience
significant side loads. In the real world this is simply not true.
> And in the days before affordable
> and reliable spoke tensiometers were available. And before rim makers
> speced maximum spoke tensions.
So, rim makers spec maximum spoke tension, that doesn't mean you
should go tyhere or that you need a hoogywotsit to build excellent
wheels. In my opinion, the use of a hoogywotsit is detrimental to the
development of good wheelbuilding practice for it highlights a
relatively insignificant part of building bicycle wheels, that of
reproducibility in ahigh production environment.
>
> Today, with modern rims, it *is* a recipe for an overtensioned rim
> which will fail prematurely due to cracks around the spoke holes.
The JB rant is a recipe for disaster on plenty of rims because he
focussed on one tiny little part of a spoke and didn't b0other to
look where it led to. Just looking 4" along the spoke and it is clear
to anyone with eyes looking at an interlaced spoke wheel that the
spokes are diverted and need to bend around each other. But the
engineer ignored this for he had this false idea that overtensioning
spokes saved them from fatigue. WRONG. And so the tale is told again
and again. Spokes break, build tighter, wheel buckles, build tighter,
rim splits, oh well maybe not quite that tigtght, but real tight
because the FEA and hanging/standing and T&S and you're looking at it
gozzy. DUH, it doesnt work. Especially with stainless spokes which
do not self set when interlacing as do softer carbon steel spokes.
AMuzi
http://www.yellowjersey.org/photosfromthepast/CANEWHUB.JPG
http://www.yellowjersey.org/photosfromthepast/yeasowat.jpg
True but not an absolutely critical dimension for most riders.
thirty-six
It's a ridiculous idea NOT to use threadlock on a double wall rim. It
is the first threaded part of the bike subjected to the highest level
of vibration. There is no locking nut to adjust the spoke length and
there is so inbuilt facility for wiring. As the nipple needs to be
adjusted precisely then threadlock performs the function of securing
the length of the spoke. The alternative is to use a rubber rim tape
on a single wall rim. In the days before high pressure rims, the rim
tape secured the nipple position on wired-on rims and the alternative
was generally track rims which had their nipples secured by dabbing
the cement on the ends of the spoke and nipple when applying the first
tyre. With mastic used on road tubs this technique does not work so
well and the use of linseed is ideal if you dont want to crack open
the can of track cement..
Qui si parla Campagnolo
My Aunt Matilda's mustache.
I have seen one broken axle on a Campagnolo freehub type rear hub. Of
the steel, 12mm cassette type axles. I have build hundreds(thousand?)
rear wheels using Campagnolo hubs, DT spokes and 'standard' rims of a
variety of manufacturers and they work just fine. I am very
conservative in my wheelbuilding philosophy, if the rider is heavier,
either in technique or gross tonnage, I use a heavier rim, more spokes
and double butted spokes. I don't build wheels that I KNOW will not be
appropriate for the rider. 4 spokes here and there, 50-100 grams make
no real difference in rider performance unless the wheel goes to hell
and that has a BIG impact on rider performance, as he stops and gets
his cellie out for a rescue.
z
I had the DS "cone" break in half on a '97 rear hub. Which, of course,
damaged the finish on the corresponding race.
thirty-six
>
> My Aunt Matilda's mustache.
>
> I have seen one broken axle on a Campagnolo freehub type rear hub. Of
> the steel, 12mm cassette type axles. I have build hundreds(thousand?)
> rear wheels using Campagnolo hubs, DT spokes and 'standard' rims of a
> variety of manufacturers and they work just fine. I am very
> conservative in my wheelbuilding philosophy, if the rider is heavier,
> either in technique or gross tonnage, I use a heavier rim, more spokes
> and double butted spokes.
What sort of radial displacement do you aim for with load in order to
protect the hub from shock loading?
Qui si parla Campagnolo
Very unusual. Seen more than a few get pitted and of course, they are
easy to change but breaking one is unusual.
Jobst Brandt
>>> My Aunt Matilda's mustache.
>>> I have seen one broken axle on a Campagnolo freehub type rear hub.
>>> Of the steel, 12mm cassette type axles. I have build hundreds
>>> (thousand?) rear wheels using Campagnolo hubs, DT spokes and
>>> 'standard' rims of a variety of manufacturers and they work just
>>> fine. I am very conservative in my wheelbuilding philosophy, if
>>> the rider is heavier, either in technique or gross tonnage, I use
>>> a heavier rim, more spokes and double butted spokes. I don't
>>> build wheels that I KNOW will not be appropriate for the rider. 4
>>> spokes here and there, 50-100 grams make no real difference in
>>> rider performance unless the wheel goes to hell and that has a BIG
>>> impact on rider performance, as he stops and gets his cellie out
>>> for a rescue.
>> I had the DS "cone" break in half on a '97 rear hub. Which, of
>> course, damaged the finish on the corresponding race.
> Very unusual. Seen more than a few get pitted and of course, they
> are easy to change but breaking one is unusual.
The main cause of bearing failures on QR hubs is axial compression
from tightly closing the QR. The "over center" force one feels as the
lever closes is stretch in the skewer and compression of the axle
(about half as much as the skewer) less than 0.1 mm usually. That
occurring on "perfectly adjusted cones" is enough to exceed their load
bearing abilities and it occurs more often than it should because
riders try to be safe from wheel separation by overtightening their
QR's.
The way to test for this is to lift the wheel and allow it to rotate
slowly about its heavy position and watch that it doesn't come to an
oscillating (binding) stop. I came across this many years ago when
riders with loose bearings wanted to make an adjustment before a ride,
to which I just tightened their Campagnolo QR and we all got on the
ride, subito, with no loose bearings.
Jobst Brandt
bfd
wrote:
> > I had the DS "cone" break in half on a '97 rear hub. Which, of course,
> > damaged the finish on the corresponding race.
>
> Very unusual. Seen more than a few get pitted and of course, they are
> easy to change but breaking one is unusual.
Broken cones are not restricted to Campy hub. I had a left cone on a
Dura Ace FRONT hub crack. When I went in to overhaul the bearings, I
found the cone cracked in half. It wasn't cheap either:
http://aebike.com/page.cfm?action=details&Affiliate=3&PageID=30&SKU=HU3561
I didn't realize later that DA had a 3 year warranty. It broke at
about 2 and 1/2 year, so maybe I could have had this warranty? Oh
well, bought a replacement and haven't had a problem since. Good Luck!
thirty-six
> The main cause of bearing failures on QR hubs is axial compression
> from tightly closing the QR.
Rarely do people overtighten QR's because its simply not possible
unless you add leverage.
Inadequate lubrication and poorly adjusted bearings are the cause of
bearing failure.
> The "over center" force one feels as the
> lever closes is stretch in the skewer and compression of the axle
> (about half as much as the skewer) less than 0.1 mm usually. That
> occurring on "perfectly adjusted cones" is enough to exceed their load
> bearing abilities and it occurs more often than it should because
> riders try to be safe from wheel separation by overtightening their
> QR's.
BECAUSE of incorresct cone adjustment and low lubricity of lubricant
under increased pressure. Better lubricants cope with the increased
pressure. That is not meant to encourage poor adjustment, it merely
gives more leeway.
>
> The way to test for this is to lift the wheel and allow it to rotate
> slowly about its heavy position and watch that it doesn't come to an
> oscillating (binding) stop. I came across this many years ago when
> riders with loose bearings wanted to make an adjustment before a ride,
> to which I just tightened their Campagnolo QR and we all got on the
> ride, subito, with no loose bearings.
Use oil and you will see the wheel turn at a slow rate for ten minutes
if it is balanced in and in still air. The obvious effortlessness
compared to greasing is easy to see. A poor adjustment is easier to
see when oiled. If you cant regularly use an oil can for whatever
peculier reason or belief, then find a way of removing the bearing
caps with the axle in place to clean and grease up, or use a fluid
pumping grease and inject from the inside (wrt wheel) of the bearing
shell.