Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site reed.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tektronix!reed!kehoe
From: kehoe@reed.UUCP (Dave Kehoe)
Newsgroups: net.bicycle
Subject: Tire Inflation, Brakes
Message-ID: <1926@reed.UUCP>
Date: Mon, 23-Sep-85 23:22:19 EDT
Article-I.D.: reed.1926
Posted: Mon Sep 23 23:22:19 1985
Date-Received: Thu, 26-Sep-85 07:15:05 EDT
References: <285@ncr-sd.UUCP> <38200052@uiucdcs> <2830@think.ARPA>
Reply-To: kehoe@reed.UUCP (Dave Kehoe)
Organization: Reed College, Portland, Oregon
Lines: 41

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