dishing 120mm rear wheel to 126mm: can it be done?
Brad Carlson
It is becoming harder and harder to find 120mm freewheels, and I am
considering (gently) cold-setting the dropouts to 126mm and redishing
the wheels 3mm towards the freewheel. I have trued my own wheels for
a while, but have never had to do any serious dishing. Also, I'm not
sure the spokes with their present tensions would even allow for such
a large change using normal truing techniques.
Should I loosen all the spokes and start over "from scratch" with
untensioned spokes? Is this all a crazy idea, and should I resign myself
to a fate of scrounging for "Schwinn-approved" 120mm era freewheels and
a life within ten speeds?
-Brad
--
PAPER-NET:c/o Saint Olaf College, 1500 St.Olaf Ave., Northfield MN 55057-1001
APPLIANCE-NET: (507) 663-6445 *REAL*-NET: carl...@stolaf.edu
Dave Hall (Sverdrup)
>I have a couple of nice older frames that have 120mm rear dropouts.
>It is becoming harder and harder to find 120mm freewheels, and I am
>considering (gently) cold-setting the dropouts to 126mm and redishing
>the wheels 3mm towards the freewheel. I have trued my own wheels for
>a while, but have never had to do any serious dishing. Also, I'm not
>sure the spokes with their present tensions would even allow for such
>a large change using normal truing techniques.
>
between the outermost cone retention nuts had better be 126 mm too. You
MAY be able to insert shims/washers, but this could leave you without
enough axle
shaft protruding to allow proper mounting of the wheel in the dropouts.
Replacing the axle shaft is probably best, IF you can find one that is
compatible with your hub bearings, yet longer than the original (good
luck). The alternative is to replace the whole hub. This is a great time
to also replace (possibly worn) spokes. So, if you are going to replace the
hub and spokes, and if your rims are the same vintage as the frame, why not
buy a whole new wheel?
>
>Should I loosen all the spokes and start over "from scratch" with
>untensioned spokes? Is this all a crazy idea, and should I resign myself
>to a fate of scrounging for "Schwinn-approved" 120mm era freewheels and
>a life within ten speeds>
Perhaps the oracle (Jobst) can speak to this better than I.
Dave H.
andrew.vida-szucs
>I have a couple of nice older frames that have 120mm rear dropouts.
>It is becoming harder and harder to find 120mm freewheels, and I am
>considering (gently) cold-setting the dropouts to 126mm and redishing
>the wheels 3mm towards the freewheel. I have trued my own wheels for
>a while, but have never had to do any serious dishing. Also, I'm not
>sure the spokes with their present tensions would even allow for such
>a large change using normal truing techniques.
First of all be careful when bending your stays. Obviously you want
to bend each stay equally outward so your wheel alignment doesn't go
to hell on you. This takes great care because these thin walled
cold drawn tubes fatigue rather quickly once their elastic limit has
been exceeded, meaning that you can't keep bending them back and forth
too many times.
Ragarding the wheels... Re-dish??? I assume you mean to use new hubs,
which means building a wheel from scratch, unless I am misunderstanding
your post. I tend to think new spokes will be in order because the
lengths will probably not be right, though you could try to relace
with the old ones if you don't mind the possibility of having to take it
all apart again if you find out they are too short.
Jim Delwiche
>
> Ragarding the wheels... Re-dish??? I assume you mean to use new hubs,
> which means building a wheel from scratch, unless I am misunderstanding
> your post.
I assumed he meant he was going to insert a longer axle and a spacer
on the right side of the wheel to make the offset correct.
I agree that the touchy part is bending the rear dropouts apart
without trashing the frame. I think it would be safer to use a torch
and remove the rear brake hanger before bending anything.
Tom Reingold
$ I assumed he meant he was going to insert a longer axle and a spacer
$ on the right side of the wheel to make the offset correct.
$ I agree that the touchy part is bending the rear dropouts apart
$ without trashing the frame. I think it would be safer to use a torch
$ and remove the rear brake hanger before bending anything.
I would recommend against this. It's not a big deal to spread the
frame this small amount. I've done it to a few bikes without any
problems. Taking a torch to the bike would ruin the paint job. It is
unnecessary trouble. You don't need to remove the brake bridge.
--
Tom Reingold
t...@samadams.princeton.edu OR ...!princeton!samadams!tr
"Warning: Do not drive with Auto-Shade in place. Remove
from windshield before starting ignition."
jobst_b...@hp1900.desk.hp.com
> I have a couple of nice older frames that have 120mm rear dropouts.
> It is becoming harder and harder to find 120mm freewheels, and I am
> considering (gently) cold-setting the dropouts to 126mm and redishing
> the wheels 3mm towards the freewheel. I have trued my own wheels for
> a while, but have never had to do any serious dishing. Also, I'm not
> sure the spokes with their present tensions would even allow for such
> a large change using normal truing techniques.
>
> Should I loosen all the spokes and start over "from scratch" with
> untensioned spokes? Is this all a crazy idea, and should I resign myself
> to a fate of scrounging for "Schwinn-approved" 120mm era freewheels and
> a life within ten speeds?
I look at this as two separate problems. How to offset a rear wheel and
whether a bike should be widened from 120 to 126 mm dropout spacing.
About the wheel: This is a simple matter if you spoke wheels at all but
since you ask I might guess that you don't. Yes, loosen the spokes on
the left side a half turn and then tighten the ones on the right a half
turn and check the center with a centering bridge. Note that the steeper
angle on the right spokes means that they are getting proportionally
tighter than the left ones are getting looser in absolute force. If
these are older wheels, put a drop of light weight oil on every nipple
at the penetration into the rim.
There is little reason to change from a 120 spacing because an Ultra-six
Sun Tour New Winner Pro (wow what a name) is about the same width as the
five speed standard spaced freewheel around which the 120 spacing was
designed. Because the disparity in spoke tension goes asymptotically to
infinity with increasing offset, the shift to more sprockets is not a good
course to follow. To reduce this disparity with 7 and 8 sprocket clusters,
new cassette hubs use diminishingly narrower flange spacing. This reduces
tension differences but also makes a weaker rear wheel laterally.
You may scoff at this suggestion but since no one is taking data, we have
no numerical proof but it is my impression that there are more rear wheel
collapses these days than in the days of 5 speed Campagnolo wheels. This
observation isn't worth much because there is a completely different
range of riders now than then. However, what makes me believe there must
be more than there would otherwise be, is that measured and calculated,
these wheels are substantially softer laterally.
I find that my old Campagnolo Record hubs with 5 speed axles and 120 mm
dropout spacing work fine and allow a great selection of gears from
Sun Tour. I like these hubs and see no need to scrap them. Unless
riding on a 30 year old design goes against your grain, this arrangement
is hard to beat. In fact, had Regina freewheels not failed me so
miserably, I probably would still be riding a 5 speed.
Tom Reingold
are getting very hard to find. Is this really true? It seems to me
that if you can still find them, you are better off sticking with
five-speed spacing and ultra-six freewheels.
William Warburton
|> It's called cold setting, and is the accepted method for all steel
|> frames (including the $1000+ racing frames). I assume it is acceptable
.....
|> I recomend sending it to the pros.
I'd like to extend this discussion a bit for my own ends.
I have an old Reynolds touring frame (it was my father's, built in the 60s by
a London based builder called "McLean") which has a narrow rear triangle.
I had a fair bit of work done to it a couple of years ago when I sheared a
dropout- It was going to need respraying anyway so I got braze-ons put on it
for cantilevers and some other stuff (I can hear the traditionalists' appalled
gasps from here!) but I didn't take the opportunity to get the triangle
widened.
I am using a suntour winner pro freewheel on the bike now. This is a six-cog
compact cluster (same width as standard five) on a campy record hub and the
back wheel is set up off-centre in the dropouts in order to get room for the
freewheel. I think I probably have some chain line problems too :-). However
it all works quite well (No indexing simplifies things hugely!).
I think I will probably get the triangle spread quite soon in order to
simplify the setup (it's a bit of a pain juggling the rear hub to make it all
work at the moment) but I am not really sure what size to get it set to.
Is it safe to get it widened to 130mm? (I don't actually know what size it is
at the moment- I think it's less than 120mm. The bike had a three speed 1/8"
derailleur setup originally if that's any help)
Should I get it set to 120mm? 126mm? 130mm? something else?
There seems to be something to be said for using ATB sizing (since good tour-
ing parts are becoming harder to find and ATB parts are closest in function)
but I am worried about overdoing things- especially since ATB parts are
designed for different frame geometry.
Thanks for your input,folks.
W.
PS I am going to Ireland for two weeks on Saturday- I apologise in advance for
the delay in responding to anyone who sends me an answer. I am not entirely
sure how long rec.bikes articles will stay active here (Scott?) so if you would
like to mail me a copy of any posting you make that is relevant I will be very
grateful. Sorry about this, I know it's bad netiquette but I wanted to catch
the thread while it was active.
Timothy Smith
>ji...@gold.gvg.tek.com (Jim Delwiche) writes:
>
>$ I agree that the touchy part is bending the rear dropouts apart
>$ without trashing the frame. I think it would be safer to use a torch
>$ and remove the rear brake hanger before bending anything.
>
>I would recommend against this.
I second the motion! DON'T USE A TORCH!! For a cheap frame it's
unnessesary, and for an expensive frame it may ruin it. It's not a
good idea to use tractor repair techniques on aircraft quality components.
>It's not a big deal to spread the
>frame this small amount. I've done it to a few bikes without any
>problems.
It's called cold setting, and is the accepted method for all steel
frames (including the $1000+ racing frames). I assume it is acceptable
on aluminum frames, but don't quote me. Call the manufacturer. Composite
frames, i.e. carbon fiber, kevlar, etc., will not take a permanent set.
At best you'll get tired without breaking the frame, at worst...
The trick to cold setting is to get the bend right the first
time. Bending the frame back and forth weakens it. Bending it once
is fine, as long as the bend is small. (3mm per dropout is small.)
Use a slow pull, and brace the frame well. If after the pull the dropout
is short of the 3 mm, that's fine, give it a bit more. If it's over
3mm you goofed. It will have to come back.
Measure your progress with a string and a ruler. First, is the
frame straight? Hold one end of the string on the dropout and the other
against the head tube. Pull the string taught and with your third hand
measure the distance between the string and the seat tube. Repeat for
the other side. The two measurements should be identical. If not, use
the cold setting process to bring them equal (at a 126mm width, of course)
Plan every set, and do as few as possible. Typically the frame is already
out of alignment, so 4 mm on one side and 2mm on the other are common.
>Taking a torch to the bike would ruin the paint job. It is
>unnecessary trouble.
It may also change the crystaline structure of the fancy steel which
you paid so much for. DON'T DO IT!
> You don't need to remove the brake bridge.
DON'T REMOVE ANYTHING! It's just a little bending, no big deal. It was
cold set at the factory to get it aligned. One more set in the frames
lifetime won't hurt it. Just do it carefuly.
A good bike shop will charge a nominal fee for the whole thing.
I recomend sending it to the pros.
> Tom Reingold
Tim Smith
andrew.vida-szucs
[deletions]
> I have an old Reynolds touring frame (it was my father's, built in the 60s by
>a London based builder called "McLean") which has a narrow rear triangle.
If it is 531 then I would say setting to 130 shouldn't be a problem
especially since it is a touring frame and hence the stays are probably
a bit longer. If it is a 753 frame, DON"T TOUCH IT! These tubes
cannot be cold set at all. I forgot to mention this in the previous
post.
[more deletions]
>
> Should I get it set to 120mm? 126mm? 130mm? something else?
>
> There seems to be something to be said for using ATB sizing (since good tour-
>ing parts are becoming harder to find and ATB parts are closest in function)
>but I am worried about overdoing things- especially since ATB parts are
>designed for different frame geometry.
>
The extra 2mm/stay to go to 130mm should not make a difference as far
as the stays are concerned.
BTW, one way to better assure equal spreading of both sides of the
frame is to use a jacking device beteeen the drops, and expanding
the width of the triangle from both sides simultaneously. A
machinists jack should be good for this, though any device that can fit
between the dropouts and apply the needed movement should suffice.
See below:
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
Stays------------>/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ / \ \
/ /<---------Direction of expansion----------------->\ \
| | _ ____________________________ | |
| | | | | | | |
| | | |_________________| | | |
Drop--> | | | | | Jacking device | | |
| | | |_________________| | | |
| | | | | | | |
|__| |_| |____________________________| |__|
Hope this helps.
-Andy V.
Ray Ager
learnt to bunny hop on the MTB, I now hop the odd hole in the road on the
road bike. What I'd really like to know is: are the rims (Durex Ambrosio
19mm) strong enough to take this?
So far they seem perfectly ok and are still running true. The bike is fairly
light, Vitus 979 Aluminium frame, and I weigh about 11st 8lb (73kg). I think
I'm fairly light jumping and usually land lightly and smoothly. It seems a
better technique than hitting the odd unavoidable hole in the road (and it's
fun!).
Any comments, please?
--
Ray Ager ag...@rtf.bt.co.uk
...uunet!ukc!axion!rtf!ager
David Mackintosh
damaged a rim by bunny (or any other small furry creature) hopping.
IMHO, hopping pavement joints, potholes, and other sharp surface
irregularities will be much less likely to cause wheel damage than
impacting the obstacles themselves.
I use middle-weight tubular rims (GL 330s) with 32 14/15 ga. DT spokes
for training and racing and have never broken a spoke. I have also
found that using these spokes over straight 14 ga. requires much less
truing due to their greater elasticity (Jobst, it works!).
Well, actually I did brake several spokes when my rear derailleur blew
up and swung into the wheel a few weeks ago but that's another story.
David Mackintosh
Bradburn
> If it is 531 then I would say setting to 130 shouldn't be a problem
> especially since it is a touring frame and hence the stays are probably
> a bit longer. If it is a 753 frame, DON"T TOUCH IT! These tubes
> cannot be cold set at all. I forgot to mention this in the previous
> post.
From _Bicycle Metallurgy for the Cyclist_, "Contrary to popular
belief, Reynolds 753 and 531 tubing have identical chemical
compositions; it is the heat treatment that makes them quite
different." Theres a table that says:
Brand Tensile Strength Yield Strength
(lb/sq. in) (lb/sq. in)
531 116,500 100,800
753 179,200 156,800
It seems to me that if their chemical compositions are the same,
you should be able to cold set them both, or not. This view is
reinforced by the fact that both have a yield strength below the
tensile strength (if it weren't, it would break instead of bending,
right?) Where's the metallurgist, Arnie?
Also, I have a question: if you can't cold-set 753, does that mean
that the framebuilder has to get the angles brazed exactly right
the first time? I know many framebuilders depend heavily on cold-
setting to get things just right...
Why doesn't someone with a 753 frame get their dropouts spread to
130mm, as an experiment? If it doesn't work out, I'll send them
my sympathy. :-)
Matthew.
Craig Durland
Andy V. sez:
> If it is a 753 frame, DON"T TOUCH IT! These tubes cannot be cold set at
> all.
Are you sure about this? I thought 753 was about the same as Tange
Prestige and I have no problems raking Prestige forks (a massive cold
set).
> BTW, one way to better assure equal spreading of both sides of
> the frame is to use a jacking device beteeen the drops, and
> expanding the width of the triangle from both sides
> simultaneously.
I not convinced that this would ensure equal spreading - do to the way
chainstays are brazed, dented, etc, they seem to want to bend
differently from each other (in my experience).
Craig Durland (503) 750-3354
Hewlett-Packard, 1000 NE Circle, Corvallis, OR 97330
cr...@cv.hp.com
Javier Pinto
>I weigh 180 lbs, have been as heavy as 210 (I'm 6'-3") and have never
>damaged a rim by bunny (or any other small furry creature) hopping.
>IMHO, hopping pavement joints, potholes, and other sharp surface
>irregularities will be much less likely to cause wheel damage than
>impacting the obstacles themselves.
I'd like to learn bunny hopping. It looks like fun and also like a good
thing to do in some situations. Recommendations? I only ride road bikes in
case it matters.
Javier.
st...@alcvax.pfc.mit.edu
They are, but it is not a good idea in general. I have gotten big dents in my
rims from not jumping far enough. The other times I have gotten big flat spots
is when I didn't see a bump or hole, so I couldn't have jumped it anyway.
On to
oops
So I have given up on trying to hop potholes etc. Just get your butt off the
seat and try to let the bike float underneath you when you go over an unavoidable bump.
Also few things are more annoying on a training ride than riding behind
some bozo who insists on jumping every little bump.
Les Earnest
>I've had to dust off my road bike having recently had my MTB stolen. Having
>learnt to bunny hop on the MTB, I now hop the odd hole in the road on the
>road bike. What I'd really like to know is: are the rims (Durex Ambrosio
>19mm) strong enough to take this?
Ther is experimental evidence that if you jump a ditch and the rear
wheel comes down on the far edge and if you weigh as much as I do,
even strong rims tend to become pretzeloid. :-[
--
Les Earnest Phone: 415 941-3984
Internet: L...@cs.Stanford.edu USMail: 12769 Dianne Drive
UUCP: . . . decwrl!cs.Stanford.edu!Les Los Altos Hills, CA 94022
David Mackintosh
be done by a builder. The last time I was at my builder's shop he was
working on a new 753 frame for Betsy King who had neglected to tell
him that it was for an 8-speed setup, so he was spreading the triangle
after it had been brazed. Apparantly 753 has to be pulled farther
before it takes a set (higher yield stress) and the frame is more likely
to be damaged (brake bridge popping off) than with other tubing. One
possibility might be to put a clamp across the two seatstays at the
brake bridge in order to keep them from seperating.
David Mackintosh
Sam Henry
(Craig Durland) writes:
>I not convinced that this (using a jacking device) would ensure equal
>spreading - do to the way chainstays are brazed, dented, etc, they
>seem to want to bend differently from each other (in my experience).
>
> Craig Durland
it would seem to me (not having done this, but comtemplating it) that
the technique would be:
* insure the drop-outs are parallel
* use the jacking device to spread the seat stays, which would carry
the chain stays with them.
the whole thing should be parallel and the right distance when done?
--
sam henry <she...@rice.edu>
Proud driver of the blue Ross dump truck!
Wanna ride?
Aragorn
Well, I bunny hop railroad tracks on my road bike (only if I'm going
faster than 25 mph) with no ill effects. My wheels are Wolber T430
Alpine with 32-hole 14 gage spokes. The purpose of bunny hopping (someone
correct me if I'm wrong) is to reduce the chance of the rim failing. The
edge of a pothole will cause a point load, while the hop will cause a
more distributed load. The point load is more likely to cause the rim
to fail. Also, the way Jobst explains it, most rims are overbuilt and
can withstand much higher loads.
Aragorn, the Elfstone
--
***sean...@ecn.purdue.edu***********************************************
* Inigo: "You seem a decent fellow. I hate to kill you." *
* Man-in-Black: "You seem a decent fellow. I hate to die." *
* _The Princess Bride_ *
Paul Thompson
>I've had to dust off my road bike having recently had my MTB stolen. Having
Welcome back to the world of REAL (tm) bikes!
>learnt to bunny hop on the MTB, I now hop the odd hole in the road on the
>road bike. What I'd really like to know is: are the rims (Durex Ambrosio
>19mm) strong enough to take this?
I ride Mavic GP4 32 spoke rims which may be a little stronger than the
Ambrosio rims. As yet, 5-6 years, i've had no problems bunny hopping. If
you watch the pros they all do it, and it's certainly better than riding
through pot holes which really can do some serious damage to tubs and
the rim.
Paul.
--
-------------------------------------------------------------------------------
Paul Thompson, | Bitnet: pa...@btcase.bt.co.uk
British Telecomunications plc, | Tel: 071-831 6268
BT/D&P/ISD/DDS445, | Fax: 071-831 9978
Ray Ager
>
> [other quoted article deleted]
>
>I'd like to learn bunny hopping. It looks like fun and also like a good
>thing to do in some situations. Recommendations? I only ride road bikes in
>case it matters.
>
>Javier.
Recommendation no 1/DISCLAIMER: learn on a mountain bike! The rims are much
tougher and you can find some soft grass to practise on, in case you fall off.
*Don't* ruin your best road rims trying to learn. Wear a helmet.
The way I learnt was to first 'hop' the front wheel and the back wheel
separately. The front is easy: basically pull up on the bars and the wheel
will lift.
The back I found a bit more difficult: in fact, at first it just seemed
impossible! Part of the problem was just to 'imagine' it could be done and
eventually it was. Hard to describe but you sort of push down on the pedals,
push your weight forward and 'pivot' on the bars, and the back wheel will
hop.
My next stage was to clear obstacles by lifting the front wheel then follow
by lifting the back. Eventually, after *much* practice, this became one
smooth jump, lifting the whole bike at once, rather than each wheel
separately - again it was partly a psychological 'jump': watching others do
it, convincing myself I could do it too and eventually I could.
I did have a good incentive: I badly buckled the rear rim on my mountain
bike when I hit a deep rut at speed. I was still jumping the front and back
wheels separately: the front was ok but I wasn't quick enough to follow with
the back and it hit the rut.
Just before my bike was stolen I rode the same track again at speed and made
a *perfect* jump with the whole bike to clear the rut - it was great!
Go out and get practising - don't give up. Keep at it and you will succeed.
Let the net know how you get on.
Incidentally, the world (?) record bunny hop is 40" made by Bunny Hop Master
'Batty' Mark Batts - mine is probably closer to 3"!
Harry Phinney
>(Craig Durland) writes:
>>I not convinced that this (using a jacking device) would ensure equal
>>spreading
> it would seem to me (not having done this, but comtemplating it) that
> the technique would be:
> * insure the drop-outs are parallel
>
> * use the jacking device to spread the seat stays, which would carry
> the chain stays with them.
Both the seat stays and chainstays must be bent in this process.
Craig's point was that a jack will apply equal force to the two
dropouts, while the two chainstays will have different strengths due to
the differences in denting (at least). One of the chainstays will bend
first and more than the other. The dropouts will be (very) slightly
askew afterwards regardless of the spreading technique, and should be
checked/corrected afterward.
Harry Phinney ha...@hp-pcd.cv.hp.com
runner
> Incidentally, the world (?) record bunny hop is 40" made by Bunny Hop Master
> 'Batty' Mark Batts - mine is probably closer to 3"!
> --
> Ray Ager ag...@rtf.bt.co.uk
> ...uunet!ukc!axion!rtf!ager
I think this was the guy I saw on the David Letterman show one night about
6 months ago. He rode down the aisle past the audience one step at a time.
No big deal, right? He then rode up a ramp to the stage and balanced in
front of Letterman's desk. Then, he bunny-hopped his bike onto the desk! I
was very impressed. Afterward he did some icredible exhibition on this multi-box
construction where he jumped all over the place.
Now that was entertaining tv.
Ray Ager
bunny hopping on road rims is ok and much better than crashing in to
pot-holes.
To those who sent e-mail: thanks also. I hope you got my replies; our
out-going mail system is a bit unpredictable, so apologies if you didn't. If
anybody needs further information, please try again.
Happy bunny hopping!
Arnie Berger
/ hp-lsd:rec.bicycles / m...@sequent.com (Bradburn) / 9:54 pm Jun 20, 1991 /
Matthew Bradburn writes,
>From _Bicycle Metallurgy for the Cyclist_, "Contrary to popular
>belief, Reynolds 753 and 531 tubing have identical chemical
>compositions; it is the heat treatment that makes them quite
>different." Theres a table that says:
> Brand Tensile Strength Yield Strength
> (lb/sq. in) (lb/sq. in)
> 531 116,500 100,800
> 753 179,200 156,800
>It seems to me that if their chemical compositions are the same,
>you should be able to cold set them both, or not. This view is
>reinforced by the fact that both have a yield strength below the
>tensile strength (if it weren't, it would break instead of bending,
>right?) Where's the metallurgist, Arnie?
It OK Matthew, I'm here. The problem with most alloys (steels included)
is that they have a memory. That is, their condition at any point in time
depends upon the path taken to get their. In thermodynamic terms their
mechanical strength is not a state variable. If chemical composition was the
only factor, then it would be true that the two metals should exhibit similar
properties. However, Heat treating and mechanical working have dramatic
effects upon the microstructure of the material and its resistance to plastic
deformation.
Heat treating is an extremely complex subject. You heat treat materials
for many varied reasons. Sometimes to strengthen the metal (often by rapid
cooling, called quenching) and sometimes to relieve induced stresses
(annealing) that are induced by cold working, welding, or quenching. One
example is the process of tempering. Here you quench it to increase the
strength, but also the brittleness, then you anneal it to increase the
toughness, but also reduce the ultimate strength of the material.
I really can't comment upon cold setting 531 or 753 alloys. I can't believe
that you couldn't bend each chainstay/seatstay out two mm. However, I could
understand it if you bend 753 too far and then attempted to bend it back. That
is an excellent way to set-up a nucleation site for a crack to develop.
Arnie, the Metallurgist
----------
Arnie Berger
arnie@hplsdvt
Telnet 590-5642