Bicycle Mechanics - v brake and brake booster problem

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View Full Version : v brake and brake booster problem


sunstealth
01-18-10, 06:30 PM
i am installing a brake booster on my spare bike and it hits the v-brake arm qhen i am actuating the brakes.

is bending the booster a viable option ?

otherwise would spacing the boostr further out be ok

and by that i mean would it neglect the effect of the brake booster or not ?


well biked
01-18-10, 06:32 PM
would spacing the boostr further out be ok

and by that i mean would it neglect the effect of the brake booster or not ?

If you have to use spacers to make it work, go ahead, no problem.

operator
01-18-10, 07:07 PM
i am installing a brake booster on my spare bike and it hits the v-brake arm qhen i am actuating the brakes.

is bending the booster a viable option ?

otherwise would spacing the boostr further out be ok

and by that i mean would it neglect the effect of the brake booster or not ?

Brakeboosters are worthless in the first place...


well biked
01-18-10, 07:32 PM
Brakeboosters are worthless in the first place...
Useless unless you have brakes that squeeze so hard they flex the seatstays. Then they're damned nice.

BCRider
01-18-10, 11:07 PM
Brakeboosters are worthless in the first place...

THIS IS 100% WRONG! ! ! !

How can you say something like this with a straight face?

I recently did some modding to my old Norco Rampage. One of the old school steel frames from back when light weight and quality went hand in hand. But with that lightness came some pretty apparent flexing. The boosters produced TWO instantly felt improvements. First, of course, the lever felt SO much more solid thanks to reducing the frame flex. The second was that the brakes actually stopped with less lever pressure needed for the same stopping power. Likely because the arms don't twist outwards as much so the pads stay flatter to the rim faces.

I always thought brake boosters were the hieght of geekiness until I saw how much the stays were flexing and thought I'd try one. Now my bike is sporting a pair and I'm proud to have them on there. Form follows function and these things really do function.

Sunstealth I had to shim mine slightly to clear my Avid Arch Rivals. You can use the aluminium cup washers from an old worn brake shoe. You'll need to file the hole out a little but it'll work and they come in two convienient thicknesses so you can use the one you need. If by some chance your arm bolt is now only going in about 3 to 5 mm worth of thread into the pins then get some longer bolts. You really do want to have more around 7 to 8mm minimum of thread engagement. With the booster the bolts aren't just holding on the arms anymore. There's now side forces on those bolts thanks to the booster and you want at least a good 7 to 8 mm worth of thread engagement to help support the bolts. If there isn't enough the side forces could make the bolts work loose.

bikinfool
01-19-10, 02:16 AM
I run two brake boosters, one on an OCLV and one on a Moots YBB. Tried both without before with, prefer the stiffer stays with; you can see as well as feel the difference. One's a Shimano Carbon V-Brake Booster, the other a no-name carbon model I picked up on sale. I haven't traded them between bikes but pretty sure the Shimano's a bit stiffer. Spacers and bolts came with both of mine, and keep them away from the brake arms, but can make adjusting the anchor bolt tricky. Definitely worth it in my experience.

sunstealth
01-19-10, 07:36 PM
ok good so now i need to track down 5 other booster the difference it made on my backup canadian tire bike is unbelievable,thank you BCrider for the pad spacer trick :) works like a charm.

dunno if theyl change something on my main offroad bike with a rear avid arch supreme V-brake ,got to try it!

BCRider
01-19-10, 07:42 PM
Well a lot will depend on how stiff the seat stays are but there's no doubt that the Avid Arch design will benifit in both feel and stopping power from having really stiffly locked down brake pins.

The reason I used the brake pad spacers was because the parts kit spacers that came with the boosters were way too big and would have just added to the kludgey look. And hell, it's bad enough as it is.... :D