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Technical & Reference Section => Tech and Restoration => Topic started by: squigly on April 12, 2011, 11:13 AM
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I'm trying to get some V-Brakes set up right, they should be easy pull to a vice grip on the rims but instead they are really hard pull to a slurr on the rim, this is a front brake through a potts hollow bolt, where should i start looking to get the free movement in the lever, i've backed off all the adjusters and slackened the cable through the pinch bolt so the pads are away from the rim, if i back them off any more there's not enough pull in the lever to get the pads onto the rim !
I just cant get that 'grab' and lock up i should be getting from a fairly new system
Is there anything i can do to the rims and pads to increase performance ??
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It will be better to change a rims for better performance and grip.
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:) Strange for sure-not too many V-brakes ran on the front at all...
First off,are the locating pins inserted in the top hole of the lugs & is there plenty of tension when you push the arms in? V-brakes work best when the cable is straight so running a Potts mod isn`t ideal.Make sure the cable is well lubed & try Kool Stop BMX or sticky type pads rather than buying new rims.
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I was wondering if the cable route could be the problem ?, the rims are nothing special Alex 48's but in good little use condition and not egg shaped until i get the Tuff's on there, pad's are stock un-branded.
I think i may upgrade to a 'spoon' brake...
(http://upload.wikimedia.org/wikipedia/commons/thumb/1/11/Marian038.jpg/450px-Marian038.jpg)
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have you got a picture of your set-up, I don't think I have ever seen V-Brakes set-up with a Potts mod as the cable routing from under the forks up to the v-brake would cause the cable to foul and v-brakes don't like convoluted cable routes!
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Have you got enough pull on the lever?, V brakes dont work well with old school levers (tech 3/4) as they don't pull enough cable ( well, mine didn't anyway!)
Pics would really help
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does the forks have a hole where you would mount a caliper brake? if so you could use a canti brake and a normal lever. you usually need a v brake lever for v brakes for them to work right. i have a set of gsport prong forks that used a canti brake, i ended up drilling a hole in the forks to fit a boa brake because the canti brake just locked up when you pulled it. here's how it looks set up with a canti brake.
(http://www.gsportbmx.co.uk/custom/G%27s_bike/front%20brake2.jpg)
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I think there may be some misunderstanding....
V- brakes are not all center pull ! the ones i have are linear pull brakes, pretty common on mid-new school stuff less so on old school, similar looking to these...
(http://www.flogyourbike.com/shop/images/products/spa7051.jpg)
The levers are matched to the calipers so the levers are 'presumed' correct but i will double check, thanks for the ideas of where to look. I'll grab a pic when i can.
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:) Strange for sure-not too many V-brakes ran on the front at all...
First off,are the locating pins inserted in the top hole of the lugs & is there plenty of tension when you push the arms in? V-brakes work best when the cable is straight so running a Potts mod isn`t ideal.Make sure the cable is well lubed & try Kool Stop BMX or sticky type pads rather than buying new rims.
One Pin was out of place and the whole set up was adjusted by a blind monkey probably, good call !