From: utzoo!decvax!harpo!npoiv!alice!wookie
Newsgroups: net.auto
Title: Re: Backing up to even out brakes
Article-I.D.: alice.1473
Posted: Mon Feb  7 16:53:37 1983
Received: Wed Feb  9 02:11:58 1983
References: alice.1461 uwvax.749

Most disc brakes are considered to be "self adjusting" since the designs did
not include springs to return the pads whereas drum brakes use rather strong
springs to return the shoes to their resting position.  As the disc pads wear
more fluid enters the system at the master cylinder to take up the slack and
thus the "self adjusting" effect is evident.  Drum shoes however have to have
the slck taken out by mechanical means at the wheel.  There are new designs
coming out in disc brakes which are intended to retract the pads somewhat to
prevent the drag that otherwise occurs.  In the past the drag was considered
insignificant and also helped to clean the disc but now of course we are
concerned with every possible source of rolling resistance!

					Keith Bauer
					White Tiger Racing
					Bell Labs  Murray Hill