re: [CR]What a difference a wheel makes

(Example: Production Builders)

Date: Fri, 09 Sep 2005 20:38:37 -0400
From: "Harvey M Sachs" <sachshm@cox.net>
To: ktk1_7_0_2_8@yahoo.com, Classic Rendezvous <classicrendezvous@bikelist.org>
Subject: re: [CR]What a difference a wheel makes


Kevin Kruger's post puzzles me:

"As a result of my recent 1976 Masi GC build, I swapped some wheels around on my various bikes. One switch involved my Raysport, with Campy Tipo large flange hubs laced to fairly wide AVA tubular rims along with slightly wider tires (NOS "Criterium Sprint" tires).

Well I was pleased to find that these wheels softened up the harsher ride this short wheelbase/straight fork bike to provide quite a very comfortable ride!!!

Certain that a set of small flange hubs would change the ride ever more.

While the Raysport ranked low on my list of ride comfort before,,,,,,I really have changed my opinion with the different wheelset, and truly enjoyed the 40 miler just completed on it!!!" ++++++++++++++++++++++++ What I don't understand, Kevin, is why you attribute the difference to the wheels rather than the tires. The wheels are all-metal, and fairly well stressed, with low "compliance." On the other hand, you note that you installed slightly wider tires, which are basically just thick-walled balloons: flexible rubber held roughly in place by modest amounts of highly-comressable rubber. They compress and rebound as the contact patch moves around the tire any time the wheel is moving. The analyses I've seen - but don't claim to follow completely - would strongly implicate tires and tire pressure differences as a completely adequate explanation for what you felt. Anecdotally, I once has a Raleigh International, with the best available (27x1-1/4) tires and rims. Felt sluggish, so I sold it to a friend. He put sew-ups on, and it rode transformed, in my opinion.

So, you could be right - a measurement beats a theory any day - but wouldn't it be nice if someone expanded on the Chemnitz work, or whatever, and gave us some more complete empirical testing?

harvey sachs
mcLean va