Re: [CR]How old is too old?

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From: <gpvb1@comcast.net>
To: classicrendezvous@bikelist.org
Subject: Re: [CR]How old is too old?
Date: Tue, 14 Sep 2004 21:01:45 +0000


Absolutely, don't ride the old Campy cranks. Instead, send them postage pre-paid to me, and I will see that they are properly recycled. If they are clean-looking Strada 175s, I may even split the postage with you! ;-) It has been my experience that some folks experience breakage of these, and the vast majority of us don't. It doesn't correlate well to rider weight or power or fitness level, or even to the vintage or age of the cranks to some extent (although I would say that generally the ones that break are from 1968 to about 1985, i.e. the "classically" shaped 144 BCD ones - the earlier "boxy" ones had a beefier cross-section and that seems to be a factor). It does correlate very strongly to the total mileage on them, as it's a fatigue failure. As Phil stated, these have some well-known failure modes, but in nearly three decades of riding them almost exclusively, I've never broken one, nor has my wife, nor has anyone I've ever ridden with on a regular basis. Recently, I replaced my wife's SR cranks at about 70,000 miles pre-emptively, more for cosmetic reasons than concern over any impending failure. It certainly does happen, though, and somewhat more often with these old cranks than with most other comparable old cranks of the same period. Check out Damon Rinard's site of crank failures for pics. of lots of brands of broken crank arms. It's sobering, but it doesn't stop me from using them. Check for cracks often! Regards, Greg Parker Dexter, Michigan http://www.bicycleclassics.com

Date: Tue, 14 Sep 2004 12:52:47 -0400 From: Robert Kaufmann <kaufmann@crsa.bu.edu> To: classicrendezvous@bikelist.org Subject: [CR]How old is too old?

All:

I have checked the archives, but could not find a good answer to the following issue.

Yesterday, I snapped my second NR Campy crank arm in three years. This time, the pedal eye "ripped" on a downstroke. (I fell over, but nothing more than road rash--the frame is unscathed). The first time, the arm cracked across the arm about a inch below the eye towards the axle. The cranks were installed at my LBS, and they are very good. So, I wouldn't fault them. I ride 3000-4000 miles per year. Once or twice a week, I ride hard (20-22mph) for 1-2 hour "time trials" but I am no monster. I weigh about 150 lbs. and am about 6 feet one inch tall. Clearly, I am no sprinter. I do climb well and like to get out of the saddle.

Both cranks were from the early 1980's. Are cranks of this vintage too old to be ridden on a daily basis? I really like the "look" of the cranks and would like to keep riding them. After the most recent fall, I am a bit hesitant to go to ebay and look for "lightly used" cranks. Is it best to pay my money and take my chances or is it time to "modernize" the cranks for my everyday ride.

All suggestions welcome.

Robert Kaufmann
Newton, Massachusetts