kehoe@reed.UUCP (Dave Kehoe) (09/24/85)
First off, squeaky brakes: 1) check that all the nuts and bolts on the brakes are tight; 2) toe in the brake shoes; 3) sandpaper the rims. The only brake shoes that can be toed in without bending your brake calipers are Ed Scott's Mathauser brake shoes -- they come with neat hemisperical washers. Mathausers are all around the best brake shoes: they *stop* wet or dry, don't overheat, wear a long time. They cost about $16 a set(4), though. Tire pressures: Overinflating your tires makes your bike real fast. At speeds below 20mph most of your energy goes to overcoming rolling resistance in your tires; rolling resistance is decreased by 1) higher air pressure; 2) more flexible casings; 3) more flexible inner tubes, i.e. latex inner tubes. The latter are annoying because they need to be pumped up every morning. The flexible casing theory sounds fine on paper, but my Specialized Turbos don't feel any faster than my Specialized Tourings, or even my Specialized K4 Kevlars (no, I haven't had any flats either on my K4's). Anyway, I run my tires between 110psi and 130psi. I heard of someone running Specialized Turbo S's at 150-170psi, but I'm skeptical. Specialized tires should be able to handle over 200psi, but some rims can't. Two problems arise: 1) the bead blows off the rim -- this was a real problem on Rigida 13-19 rims, they couldn't take over 90psi, but I haven't heard of any other rims having this problem (it has to do with the design of the "hook" the bead fits under); 2) the rims blow apart. I've only seen this once, but once was enough. A cyclist was filling his tires at a gas station, and thought the gauge said 70psi when it said 170psi. He put more air in, the rim blew apart, he went to the hospital for hearing damage. He couldn't hear anything for 3 days for the ringing in his ears. I can't remember the brand of rim, but it was a "good" narrow alloy rim. Buying a bicycle: Cannondale have the best frames (except for Gary Klein's frames); also look at Bridgestone bicycles. -- "Why my thoughts are my own, when they are in, but when they are out they are another's." -- Susanna Martin, executed for witchcraft. Dave Kehoe tektronix!reed!kehoe (503) 230-9454
sutter@osu-eddie.UUCP (Bob Sutterfield) (09/25/85)
> ...I've heard > of someone running Specialized Turbo S's at 150-170psi, but > I'm skeptical. Specialized tires should be able to handle > over 200psi, but some rims can't. Two problems arise: > 1) the bead blows off the rim -- this was a real problem on > Rigida 13-19 rims, they couldn't take over 90psi, but I haven't > heard of any other rims having this problem ... I ride Turbo S's on Rigida 13-20's at 120-130 psi all the time. Even on hot days in the city, and I weigh 210 or so. I only had a blowout once: when I replaced the tire and tube incorrectly after a flat (*mucho* glass in a patch I couldn't avoid because of traffic) and the tube was pinched. Got a new tube, still using same tire - no bead or rim damage. -- Human: Bob Sutterfield Facilities Management Division The Ohio State University Instruction & Research Computer Center Workplace: Ohio Cooperative Extension Service, Computer Management Group OCES VAX System Manager/Programmer (VMS) Mail: ...cbosgd!osu-eddie!sutter.UUCP or: sutter@ohio-state.CSNET or: 2120 Fyffe Rd rm 109, Columbus OH 43210 MaBell: (614) 422 - 9034