I have an old set of Deore XT V-brakes here that I'm having a bit of trouble with.

First off, these brakes are of the "parallel" pad type, so the pad always stays perfectly parallel with the rim, the place where the pad is mounted is on a lever so it stays parallel. I think they're called "parallel push".

The problem I'm having is that it seems the arms are A: too far apart and B: the pads seem to be too wide and C: There isn't a lot of spring pressure holding the arms apart.

The obvious solution is to move the spring hole up one so it has more spring pressure, but that's the problem. You can't do that with these brakes cause then the plate that holds the pads won't be parallel to the rim (trust me... I've tried.)

Did these brakes use some sort of thin brake pad and not normal V-Brake pads? Or were they made for particularity skinny rims? I know V-brakes shouldn't be this far apart, but I see no way around that. Yes, I also used the small spacer to the inside of the mounting point instead of the big one that is usually there when you buy pads.

It certainly doesn't look right when mounted. I MADE it work by physically bending the springs out a bit (and still had to screw the adjustment screws in almost all of the way.)

EDIT: Excuse the dirt, this is my commuter and it's rained a lot recently here.




EDIT: I used to have cantilever brakes on this bike, but the dynamo light got in the way of the straddle cable, meaning I had to use a very long straddle cable, which meant the braking was awful. So obviously v brakes were the answer.

A. Take the pads off the levers and rearrange the hardware, spacers, etc.
B. Those look like the wrong pads. Suggest buying new cartridge pads for V-brakes.
C. Tighten up adjusting springs on both sides of the brakes. Small screw.
D. Buy new brakes:
https://www.performancebike.com/webap...400927__400927

A: Spacers are arranged correctly. Small one is on the inside.
B: The pads look just like these. Normal V-Brake pads.
Clarks 72mm V-Brake Pads | Chain Reaction Cycles

C: Screws are already adjusted nearly all of the way tight and to the place where both sides pull evenly.
D: Doesn't help me.

OK, take the brakes off the bike mounting studs. There are usually different holes to put the springs in on the studs, which will increase tension on the springs.

Actually D. would help you. New brakes would help.

I already tried that. It doesn't work with these brakes because of the mechanism to keep the pads parallel. (Also already mentioned that I tried it in the OP.)

Did you try bending the spring(s) to increase tension?

That fork is made for cantilever brakes. The pivot studs are too narrow for v-brakes. Another style of brake arm might work better, but . . .

[MENTION=345109]corrado33[/MENTION] the only thing you can really do to salvage this situation is try to use road pads. Shimano sells thinner inserts for their replaceable pad holders that may work for you. Search for R55C4 shoes.

Thanks all. I ended up making it certainly usable by removing ALL of the concave/convex washers between the pad and the arm. Basically it went pad-small washer-arm-rest of the washers-nut. Yes, that doesn't allow me to change the angle of the pad at all, but as it turns out the arm positions the pad perfectly. I got the idea from another set of those levers we had at the shop who had done the same thing.

Yes, it's the "wrong" fix, but it works.

I didn't want to use cantilevers again because of the reasons mentioned above. The dynamo light gets in the way of the straddle cable, making me use a very long straddle cable, which means the braking is awful...

I suppose I probably could have used those old style "L" cantilevers that look like L's and use very long straddle cables, but those are REALLY old school and would get hit on EVERY rack I ever parked in.

V-brakes fix all of those things.

EDIT: For some reasons the arms still sit "off center" a bit (even though the pads are centered on the rim). Whatever, they work well, can't complain.

Pics:

I installed a set of the XT parelleogram v-brakes for a friend. I did not run into this issue.

Here is a thread with some good info (charts and pictures) on what brake boss spacing is needed for different rim widths. It is for one specific shimano v-brake, but I would think that they are all in the same ball park:

Cantilever post spacing question (xpost)- Mtbr.com

Reading through that thread, since my bike is a cross bike, it makes sense that these aren't supposed to work. But whatever, they work a heck of a lot better than the cantis I had on there before.

Modern linear-pull brakes (that is, ones without the parallel-push linkage) are far lower profile, so they tend not to suffer from the problem that the brakes you put on did--if a bike fits cantilevers, it will fit linear-pull brakes (really, cantilevers, as well), too...barring using super wide rims.

FYI, B&M (aka BUMM, for searching purposes) makes a long, wireform mount for lights that should fit your supernova, while still providing room to access the switch. Peter White, of course, can get one for you...much quicker than ordering one from Germany. My few interactions with him, both as a shop and as a consumer, were perfectly easy; I called knowing what i wanted, he double checked that I knew what I was getting, and off it went. He does have a minimum order, though. Pick up a few extra spade connectors/some wire, maybe, while you're there.

Anyway, the neat trick with the wireform mounts is, the main cable can pass right through the middle to the transverse cable, running beneath it. The Shimano CX-50/70 cantilevers are excellent brakes, and easy to set up.

None of this stuff helps you now, but it could be filed away for future reference.

Very good information about the brakes in general. It's quite odd. I've had a hell of a time getting the brakes, light, and fenders to work on my cross check. The canti's I had on there (which were Deore LXs) were so bad that my rollerbrake in the back stopped me easier than them, even with new pads, even after those pads broke in.) The thing is, the fork bridge.. uh.. where the blades meet, is quite HIGH on the cross check, meaning the fender sits a good 1" to 2" off of the tire. (Unless you buy the problem solvers thing made to correct this exact problem). This means that it's impossible for me to fit anything between the light and the fender.

Also what is annoying is that the brake hole on the fork is very HIGH compared to the headset. I had to file the top of the light mount to get it to fit UNDER the headset. So basically the position you see it in in the pictures is the HIGHEST it can be mounted/tilted. (Because if I try to tilt it up more it hits the headset.)

So basically the light and fender are stuck in place and immovable because of the Cross check frame/fork. I debated making a bracket to move the light up and away from the frame a bit. It'd probably end up looking like a blocky "J." It'd have to be made of probably 1/8" or 3/16" steel so it doesn't bounce around too much, but it wouldn't be too hard to make. (EDIT: I suppose I could simply SPACE the light out with a spacer and a longer bolt as well. That'd be easier.)

But in reality I just ordered the problem solvers fender flute which will allow me to move the fender down closer to the tire and give me a bit more room, perhaps to mount a straddle cable in there.

I may end up not using the parallel push v-brakes. I just always thought they were super cool... They were fine for a bit on the way home from the shop, but then started squealing. We'll see if they break in at all. Perhaps it was just cause it was wet outside. We'll see.