Re: [CR]Rear axle spacing and axle breakage?


Example: Production Builders:Frejus
Date: Mon, 18 Feb 2002 06:56:51 -0800
From: "Bill Bryant" <Bill_Bryant@prodigy.net>
To: garth libre <rabbitman@mindspring.com>
Cc: classicrendezvous@bikelist.org
Subject: Re: [CR]Rear axle spacing and axle breakage?
References: <000a01c1b850$c11bbec0$fabb56d1@Marta>


Campagnolo rear axles broke from time to time. I replaced them for customers pretty often. I would also ask them to bring in their frame as well as the wheel so I could inspect the dropout alignment. It was often the culprit as much as rough roads. Once their frame was set up properly, I usually didn't see them again for the same type of repair.

The original 120mm 5-speed axles were a natural steel color. If the frame dropouts were exactly parallel, the axle could be expected to hold up well for most riders. Not suprisingly, hard usage on rough roads by larger riders seemed to cause breakage the most--but with sloppy dropout alignment (and there was a lot of that going around in the 1970s) all bets were off for anyone.

With the advent of the 126mm 6-speed units in the mid-70s, axle breakage really increased. Some time around 1980 or '81 Campy introduced a heat-treated axle that largely solved the problem. It had a black finish compared to the older bare steel finish. Also, most frame makers started getting the idea about the need for better aligned rear ends; dropouts were ~generally~ better on most brands--though there were some notable exceptions that continued shoddy building practices. Some devotees might be a little unhappy to learn of the hallowed classic brands (some of which now have fan websites dedicated to them) that regularly needed their frames "finished" by aligning the dropouts properly in the bike shop. ;-)

As to your observation about mountain bike wheels, that doesn't make sense. Those fat mtn tires soak up axle-breaking impacts far more than any 700c tubular or clincher could.

I doubt there are too many steel-colored 6-speed axles still around anymore but if you have some, install a black heat-treated model and make sure your frame dropouts are carefully aligned by a reputable mechanic or framebuilder. Having done this, you won't have to worry about rear axle breakage (barring regular riding on very rough roads.)

Bill Bryant Santa Cruz, CA

garth libre wrote:
> Now I am not a real bicycle mechanic, but I have never experienced any rear axle breakage. This week I am reading about guys on this list breaking classic Campy narrow and semi narrow hubs. I weighed 145 lbs to 155 lbs during all my adolescent years in the 60's and 70's. During the 80's I weighed the same. During the 90's I even rode mountain bikes with narrowish 6 speed spacing. I now weigh up to 160 lbs and ride mostly 7 speed narrow and track. Is someone in this group trying to tell me that if I gain 15 lbs (heavens forbid) I will start breaking axles if I don't use freehubs. I find this hard to believe, but I am open to being educated. My experience with non suspension freewheeled mountain bikes lead me to believe that one could thrash these narrow things as hard as you wanted with impunity.
>
> Is it really true that guys just a little heavier than I am can break a classic Campy narrow axle? What about Suntour and Shimano? Garth Libre, afraid to gain any more weight in Surfside Fl.