Bicycle Mechanics - squishy weinmann brakes

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
geezerwheels
01-12-13, 07:23 AM
late last year I picked up a faded and incipiently rusting +\-1980 Motobecane Grand Touring for what seemed like cheap ($175) Add to that another $175 for a major tune and new Continentals--and more recently, a 6sp FW with a 34t low gear (about $80 from eBay), and new chain ($32).
I hadn't planned to keep this bike, and I certainly didn't plan on enjoying it so much--it was just meant to be something different from the basic REI stuff I'd been riding.
But now that I have gotten somewhat used to friction shifters, and the quirky handling at low speed (it is marvelous on straights, and rock steady jamming down a long hill at maybe 30-35 MPH). With the new chain and FW, the Suntour Vx-GT is now silky smooth. The result is--by gosh--I'm starting to really like this old fellow.
So, the old immutable law kicks in--the nicer you make something, the more the remaining flaws jump out and insult you.
Setting aside the whole insane subject of repainting (how much more $$$ can you sink into something for which you could never recoup), it is the Weinmann brakes that I don't like. Generally, they feel squishy and feeble. (I already removed the secondary levers, which seemed to help a little...)
So the question is, are there ways to either improve the function of the Weinmanns (better cables? better pads? Please don't tell me new rims!!!)? Or, is there another type of brake that would fit Mr. Moto?
Or should I just get over it????
Thanks in advance...
Wil Davis
01-12-13, 07:30 AM
You might try servicing the brakes. (see Park Tool site, or Sheldon Brown site for info. ) New cables (inner & outer) new pads, clean rims, true rims, all might help. HTH, Good Luck!
- Wil
cny-bikeman
01-12-13, 08:08 AM
I owned an earlier vintage Moto Grand Jubilee (still my favorite bike ever) and it came with the same centerpull Weinmann brakes. I found them more than sufficient, even with 30+ lbs of touring gear in steep hill country. Whether or not you get new cables and housing make sure that the housing is properly sized. Even bike shop prepared bikes sometimes have housing that is looped too long, especially at the handlebars. That results in some of the lever movement and pressure going into the housing instead of the calipers. Also of course if you stay with the current cable/housing make sure it's well lubricated. Use oil, not grease.
dsbrantjr
01-12-13, 09:54 AM
New pads and cables are simple and easy to do but the question which comes to my mind is how do the brakes work, that is, how do they stop the bike? Having a rock-hard lever feel does not equate to having effective brakes. Certainly there should not be slack or friction in the system but keep in mind that you are using a rather powerful lever system to squeeze rubber brake pads so you will still be able to compress them long after the brakes are locked up.
I am not certain what your major tune-up addressed but it would certainly be worthwhile to go over your system and address any shortcomings such as excess housing length, housing ends not squared off, lubrication and the like, but if you can pick the rear wheel up with the front brake and lock it with the rear one you cannot make much meaningful improvement.
LarDasse74
01-12-13, 08:27 PM
If they are the same Weinmann centre-pull calipers that I have on my commuter bike, they work acceptably, though not great. Get good cables and good pads, and diassemble the capipers and make sure everything is moving nice and smooth. There is not much more you can do.
FastJake
01-12-13, 09:14 PM
- Kool Stop brake pads
- New cables and housing, properly installed. Cable routing is very important! http://sheldonbrown.com/cables.html
Beyond those there isn't much you can do. If they are centerpulls you should be able to get decent braking, but if they are sidepulls I would trash them and get some new dual-pivot calipers. I would NOT "get over it" and just accept poor braking. You never know when you will need to stop in a hurry.
I agree - replace cables and housing (parts cost $10) following the instructions linked above, Koolstop pads ($10-20) toed in as necessary, rims trued ($5 for a spoke wrench) and braking surface cleaned (in case there's grease etc on it), brakes adjusted to a tight pad-to-rim clearance, and add adjuster barrels on the cable hangers ($10?). The braking should then be pretty good. Nothing wrong with centerpull Weimanns.
fietsbob
01-13-13, 12:27 AM
one thing about the old center pulls is they have a lot of leverage.. MA..
compare how far the pad to pivot distance , and the pivot to where the cable is , on the other side ..
it is actually greater than lots of cantilevers..
you would really have them feel even softer if using Aero
brake levers, than the Cable out the top levers from the same era.
Andrew R Stewart
01-13-13, 08:37 AM
One aspect of the Weinmann 999s is that they work best with a range of rim width. IIRC (and it's been a long time since i routeenly worked on them) a rim much narrower then 23mm makes the caliper arms pivot so far that the straddle cable geometry can loose the leverage. Of course this is somewhat dependent on the pads thickness and straddle cable length.
The last set i installed from scratch were actually DiaCompes (debatable copy) on a Fuji Finest with 21mm rims. I placed washers between the pads and the arms and ground the pads to match the rim sidewall and pad surface angles. With the Scott Mathouser pads and lined casings they work pretty well. A bit soft at the lever (a pair of Cane Creek Campy copy aeros) but powerfull enough. Andy.
Crankycrank
01-13-13, 08:45 AM
As far as replacing the cables try using some Jagwire-Racer cables and housing. These have a little less compression than any other brands (Nokon and Yokozuna etc. excepted but more $$$$) and give a noticably firmer feel.
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.