daniell

I am thinking of changing cantilever brakes to V brakes on a very old mountain bike. Do the V brakes have the same reach as cantilever brakes? Sometime ago I tried to add different cantilever brakes to this bike. The reach was different and they did not work out.

70sSanO

Most v-brakes are just a swap on old 26ers.

You will need to change the brake levers to a longer cable pull.

John

Andrew R Stewart 

The easy answer is usually yes, reach is about the same. The real answer is found by trial fitting as some brake geometries can limit or extend reach at the limits, this is dependent on rim specs and boss spacing too. Andy

squarenoise 

Echoing the above comments that it SHOULD work and of course you'll have to also swap your levers to linear pull.

Just this weekend, I swapped the canti brakes on my 1990 Trek 950 and it went smoothly. I used Tektro M730 brakes (good range of reach adjustability) and paired them with Tektro RS360A levers. The only tweak I had to make was swapping the thick/thin pad spacers on the rear brake. It's my first ever experience with V-Brakes, but the instructions were easy to follow and piece of cake to set up.

daniell

I have XTR 8 speed levers that incorporate the shifters. They are still functioning perfectly. I was thinking of going the travel agent route.

70sSanO

Are your cantis XTR M900’s?

Those are very nice brakes.

John

daniell

Only the brake lever/Shifter is XTR.

shelbyfv

It's a little concerning that the reach was wrong on the other set of cantis. Wonder which is non-standard, your existing cantis or the other set?

daniell

I was surprised too. Fortunately I was able return them. These are the brakes that I am currently using.
https://www.performancebike.com/shim...qtqhe?v=305118

thook

Are you still having trouble even with those brakes? That's a design that's been around since the early 90's, and while the Altus model line isn't "top notch" the quality and function is still there. You'd never know the difference between those and some LX tier of the same design if blind folded. Except, I guess, in either case you'd wreck
Anyway, that design has a lot of adjustment to them and, with Kool Stop salmon brake pads, they stop really well when set up properly. So, is it that you can't get those to reach or are they just not stopping well for you?

Andrew R Stewart 

The most common reasons for a canti brake to not stop as well as they could is- old and/or poor pads, too much cable friction, poor straddle cable to canti arm angle and poor pad alignment. A good set of pads (I also like KS) and possibly a different straddle length and/or brake cable and some adjustments can do wonders in many cases.

Here's a link to Sheldon Brown's site page explaining about cantis and how to set them up. The Geometry of Cantilever Brakes (sheldonbrown.com) Andy

70sSanO

If you can’t resolve your cantilever brakes and you don’t care for the travel agent, you might be able to find separate mounts for the shifter pods.

I think, but not sure these days, that a slightly later shifter mount from an STX, or LX, XT, etc. will work on your pod mounts.

If you are close to a co-op and can find a couple of non-working individual trigger shifters cheap you can separate yours from the brake levers and run a linear/v brake setup properly.

I think Delta(?) made some aftermarket flexible plastic mounts but those might be tough to find these days.

John

daniell

Thanks for your reply. I am not sure that I am following you. Are you saying that there are Shifter/lever combinations that have V brake compatible levers rather than cantilever? I did not know that was the case.
I may be beating a dead horse with this problem. I was never able to center the cantilever brakes. One block is all the way in, the other all the way out. I have already discussed this in a previous thread. First I thought that there may be a frame alignment problem. I checked the wheel for dish. Perfect. I am now thinking that the hangers might be out of alignment. If that is the case, perhaps V brakes would solve my problem.

Mr. 66

Take a picture of what you have set and post it, that will help the forum trouble shoot.

One block in one block out? Sound like a simple screw adjustment, or spring mounted in wrong position, or maybe you just need to manipulate the spring.

I would start be cleaning the brake bosses, check for clean pivoting, sometimes the brake bosses can mushroom at the top hindering the pivot action. If I recall those calipers have a plastic spring cover that break as well, that could put out of wack. We don't know what your straddle cable type or condition is.

To me it sounds like spring tension.

daniell

In the 30 years that I have had the bike I have tried everything that you suggested this is the 3rd set of brakes. I have run out of ideas.

70sSanO

Not exactly. The worst flat bar shifter design was the integrated shifter-brake setup with a single mount. Not only did it give you no adjustability, you were stuck with the package.

If you can find just the shifter mounts, not attached to the brake levers, you can swap the brake levers for compatible linear/V and mount the shifters and brake levers independent of each other.

I think the same shifter pod interface was used on later mtb shifters. If you can find some, preferably cheap non-working, just mount your XTR shifter pods to the mounts.

I have done this.

John

Mr. 66

Hard to see what's going on with the knobby tire.

The first thing I see is the pads are not set symmetric. One pad is lower than the other and the brake block are not at even measure between block holders and calipers.

That is a set screw at the bottom of the one on the drive side, that does side to side. Tighten that and it will open to the drive, loosen will open to the nondrive.

There may be an issue with the straddle housing it looks like it may be in the pinch, that housing has to be the right length or it will never center. I'm not a fan of that type of straddle.

daniell

Thanks for you input. The imbalance is so severe that the adjustment screw cannot remedy the problem. This is my 3rd set of brakes and the problem persists. It was like this 30 years ago when I bought the bike, and it remains so today.

Mr. 66

It's all spring tension, you probably need to get a little midevil on the spring(s).

I did manipulate the spring to even the tension and pull on the last set of cantis I set on my Miyata.

These are an older version of cantis I bought from a friend.

Miele Man

Yes, the housing needs to be the right length in order to be able to center those brakes.

That design of straddle cable is supposed to be a safety feature in that if a cable breaks (especially the front one) the straddle cable will not drop down onto the tire and cause the wheel to lock up.

Cheers

zandoval 

40 years ago little things like brake reach, seat and bar height, pedals, were not a big issue. I could jump from one bike or bike type to another without much difficulty. Now days its much different. A mere few millimeters in brake reach and other small things make a big difference...

daniell

I never knew that such mounts existed. I don't have a clue where to find them. If I did find them however, the cost would probably be exorbitant.

dedhed

It'd be helpful to also know the model # of the shifter/brake beyond just "XTR". Should be on it somewhere.

daniell

dedhed

One option.

​​​​​​https://www.bikeforums.net/bicycle-m...vel-agent.html