i was wondering if anyone had a point of sales system on a computer at their shop? i know that the bicycle kitchen in LA does and they were offering a copy of it to anyone that wanted it, but i have not received an email reply from them. i think that it would make keeping track of funds much easier along with helping us do our irs forms. anyone want to share their program? justin krank it up! community bicycle project tallahassee florida
From: mark@re-cycles.ca Date: Fri, 29 Feb 2008 14:10:37 -0500 To: thethinktank@bikecollectives.org Subject: Re: [TheThinkTank] direct-pull brake levers v. everything else
Below are some guidelines, courtesy of one of our former mechanics.
Mark
++++++
The difference between Canti levers and V levers (the difference you
can see) is the distance between the cable head and the lever pivot.
The larger the distance the greater the cable pull, which means less
mechanical advantage which means less scary flip-your-bike-over-but- mushy-feeling power when mated to v brakes.Many newer brake levers also have a little "v" or "c" stamped
somwhere (often on the part of the lever 'handle' that disappears
inside the lever 'body').Some other levers can be used with both V's and canti's - the point
in the lever where the cable is anchored is adjustable, either by
moving spacers and manually moving the cable head, or by twirling a
little dial. The latter is only used on higher quality (read: not
likely at most bike recycling places) levers made by Avid.And the actual distance betwen pivot and cable? I'm not really sure
exactly, but I would estimate about 2 cm for V levers and approx. 1.5
- 1cm or less for canti levers. Look at any cheap old Lee Chi's or
Di Yung's for a perfect example of a non-v lever.
If you mate canti levers with v brakes you get very mushy feeling
brakes, crazily uncontrollably powerful brakes, and very little
clearance between the pads and the rim. If you mate v levers with
canti (or caliper or U) brakes you get very low stopping power and an
extremely stiff lever feel. Its actually pretty easy to tell when
you know what you're looking for.On 29-Feb-08, at 12:50 PM, Erik Stockmeier wrote:
sheldon brown (r.i.p.) went on at length all over his website about not mixing direct-pull ("V" brake, noodle brake) brake levers with any other type of brakes & vice versa.
here is one quote, from http://www.sheldonbrown.com/canti- direct.html :
Direct-pull cantilevers have double the mechanical advantage compared with traditional brakes, so they require special brake levers. Direct-pull brake levers pull the cable twice as far, half as hard. The lower mechanical advantage of the lever compensates for the higher M.A. of the cantilever. It is not generally safe to mix and match levers/cables between direct pull and other types for this reason.
* Conventional brake levers used with direct-pull cantilevers willusually not pull enough cable to stop in wet conditions without bottoming out against the handlebars. In dry conditions, they either won't work, or will grab too suddenly.
* Direct-pull brake levers used with any other type of brakes willfeel nice and solid when you squeeze them, but due to their lower mechanical advantage you'll need to squeeze twice as hard to stop as you should, so unless you are a lightweight rider with gorilla-like paws, this combination isn't safe either.
...end quote
so my question is this... do i need to go through my personal collection of brake levers and somehow identify/separate DP levers from the rest? is there any simple way to do this? it seems like a problem i've seen many people run in to--the brakes seem fine on the stand, nonexistant when the bike goes out for a test ride. so this is probably something we should be on the lookout for, right?
ok, thanks
erik
of course there is this huge and boring page as well:
http://www.sheldonbrown.com/cantilever-geometry.html#mechanical _______________________________________________ Thethinktank mailing list Thethinktank@bikecollectives.org http://lists.bikecollectives.org/listinfo.cgi/thethinktank- bikecollectives.org
Thethinktank mailing list Thethinktank@bikecollectives.org http://lists.bikecollectives.org/listinfo.cgi/thethinktank-bikecollectives.o...
Climb to the top of the charts! Play the word scramble challenge with star power. http://club.live.com/star_shuffle.aspx?icid=starshuffle_wlmailtextlink_jan