Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site drux3.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxn!ihnp4!drutx!drux3!msw
From: msw@drux3.UUCP (Mike Walpole)
Newsgroups: net.bicycle
Subject: Re: How To Make Your Bicycle Faster (and set a new hour record)
Message-ID: <1313@drux3.UUCP>
Date: Wed, 26-Jun-85 14:39:18 EDT
Article-I.D.: drux3.1313
Posted: Wed Jun 26 14:39:18 1985
Date-Received: Thu, 27-Jun-85 06:56:48 EDT
References: <1644@reed.UUCP> <8300004@ada-uts.UUCP> <330@varian.UUCP>
Organization: AT&T Information Systems Laboratories, Denver
Lines: 26

>> > 3) Wheels.  Light wheels are important because they are revolving
>> > weight, i.e. 1 pound of tires feels like 3 pounds of frame,
>> 
>>    While 1 pound of tires might FEEL like 3 pounds of  frame,  it
>> actually  takes only 2 times more energy to accelerate 1 pound of
>> tires than 1 pound of "static" components.

>In setting the world's hour record last year, Francesco Moser used
>wheels with *heavy* rims (I don't recall the actual weight).  The
>theory was that while a little slower to accelerate, the momentum
>of the heavier rim would require less energy to keep going than a
>conventional, very light track rim.

The wheels were made of spun aluminum. The rear wheel weighed 4.5 lbs.
The disk wheels used at the Olympics were graphite and kevalar and
the rear wheel weighed 3.5 lbs.  This winter Mike Melton at the Huffy
Tech Center got the weight down to under 1.5 lbs.  This is lighter than
a regular rear wheel.  Disk wheels are used primarily to reduce wind
drag.  A bike equipted with disks front and rear will get up to a 60%
reduction in drag.  That is about 2.5 to 3 mph at racing speeds.  I
believe that the rear disk improves wind drag by 25 - 30%.  Moser
said that the wheels were weighted to keep them at speed longer.
(Conservation of momentum)  However, I believe that he was just using
the only availible technology.

Mike Walpole