RE: [CR]Reynolds & Columbus: For Lightweights Only!

(Example: Racing:Roger de Vlaeminck)

In-Reply-To: <F016848C232375449D66E2D139DFED2F01B87F1B@IMCSRV4.MITRE.ORG>
References: <299686.62715.qm@web55505.mail.re4.yahoo.com> <465F79FD.1010204@burlingtontelecom.net>
Date: Fri, 1 Jun 2007 12:21:13 -0700
To: "David G. White" <whiteknight@burlingtontelecom.net>, <classicrendezvous@bikelist.org>
From: "Jan Heine" <heine94@earthlink.net>
Subject: RE: [CR]Reynolds & Columbus: For Lightweights Only!


>David G. White wrote:
>> I was struck by that also. At 6'4" and 200# it gave me pause.
>> According to that chart (see <http://tinyurl.com/6s5yo>) I can't
>> safely ride most of my bikes. Yet none has failed on me... at least
>> to date...
>>
>> Note the fellow who created the chart says "This information, except
>> for the column on the far right, was compiled from sales catalogues
>> and correspondences with. tube manufacturers and importers." (The
>"far
>> right" column is the "maximum rider weight column"). He also says
>> "The " TYPE(s) OF CYCLING" and "MAXIMUM RIDER WEIGHT" columns are
>> intended to be only rough guidelines. Each of these can vary
>> depending upon frame size, expected frame life, desired performance
> > characteristics, weight, etc."

It all depends on how you ride, and what you do with the bike. Overall, it does not seem that lightweight tubes - used by a competent builder - make a frame very fragile. When I see that some superlight cyclocross bikes survive year after year of rough racing, then I figure that riding that type of tubing on the road has a pretty big margin of safety.

Of course, it also depends on your tire choice. I suspect that a 20 mm tire at 155 psi puts more stresses on the bike than a 37 mm tire at 55 psi - yes, those are the recommended pressures for a 220 lb. rider'/bike combo's rear wheel! (The next Bicycle Quarterly has a chart on how to achieve the same tire deflection for various tire widths and rider/bike weights. It's interesting - as Frank Berto always has pointed out, most riders underinflate narrow tires and overinflate wide tires.)

Some riders break bikes, others don't. Some heavy frames break, and some lightweight ones don't. I think it has to do more with riding style and builder skill than tubing choice and rider weight.

As for the feel, I believe that depends more on riding style than other factors. If you pedal at 115 rpm, you stress the frame differently than if you pedal at 75 rpm. Thus, it stands to reason that you might prefer a different frame.

Finally, except for fork steerer and crown failures, most frame failures are non-catastrophic. So you don't usually risk your life. I'd just keep riding the bikes you like. That certainly is what I do...

Jan Heine
Editor
Bicycle Quarterly
140 Lakeside Ave #C
Seattle WA 98122
http://www.bikequarterly.com