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