Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/3/84; site faron.UUCP Path: utzoo!linus!faron!pws From: pws@faron.UUCP (Phillip W. Servita) Newsgroups: net.bicycle Subject: Re: clincher tire pressure question Message-ID: <158@faron.UUCP> Date: Fri, 2-Nov-84 09:38:44 EST Article-I.D.: faron.158 Posted: Fri Nov 2 09:38:44 1984 Date-Received: Sat, 3-Nov-84 06:11:50 EST Reply-To: pws@faron.UUCP (Phillip W. Servita) Organization: MITRE Corp., Bedford, Ma. Lines: 31 In article dsn@umcp-cs.UUCP (Dana S. Nau) writes: >> From: kfl@hoxna.UUCP (Kenton Lee) >> >> In his "Bicycle Maintenance Manual", Eugune Sloan, a Bicycling >> magazine editor, recommends that sport clinchers be pumped up to >> 100-115 psi. Most clinchers have recommended pressures of 90-95 >> psi. Is there any danger associated with higher pressures? Is >> the reduced rolling resistance really noticable? > >There sure is--you're likely to get flat tires that way. Several >times when riding in hot weather I've gotten flat tires simply because >the tires got so hot that the air pressure got too high. >-- >Dana S. Nau >CSNet: dsn@umcp-cs ARPA: dsn@maryland >UUCP: {seismo,allegra,brl-bmd}!umcp-cs!dsn Not Quite. if anyone out there remembers his high school chemistry, the pressure difference caused by a change in temperature as extreme as 30 degrees F to 100 degrees F is pretty trivial once converted to the Kelvin scale. (it produces about a 12 percent increase in tire pressure) so if your clinchers are pumped to 100psi at 30 deg F, 100 degrees will only increase the pressure to 112psi. FAR below the safety factor of any reasonable clincher out on the market. as for a noticeable difference in rolling friction, most definitely. but i find that unless i am racing, it is not worth the extra bumps. -the venn buddhist