Installing rear Paul canti on old Litespeed Appalachian

[sgmidf]

I'm building up an Litespeed Appalachian frame/fork that I've had for a while and want to use Paul Cantis on it. The rear cable stop on the frame is at an angle. I'll admit I'm no canti expert so I don't see how this would apply force evenly. Am I missing a bracket or some other piece?
Thanks
Steve

[kramnnim]

Pictures?

As long as the cable exits the stop at the centerline of the frame, it should still work...

[EricEstlund]

Even if the brake cable exits very asymmetrically, the hanger can be scooted along the straddle cable to balance pull.

If you are referring to the canti stop being a single post rather then the traditional "U" mount, that in itself does not pose a set up or performance issue.

[sgmidf]

Here is a pic. When I squeeze the lever (ergo) it preferentially pulls the right side.

[DfCas]

Have you tried changing the spring tension on the arms? That, and moving the straddle should balance the arms. I had an Ap with Pauls and can't remember having problems.

[Bob Loblaw]

Looks fine to me, as long as there's no brake rub. If there is brake rub, you can remedy it by adjusting the spring tension.

If it's stressing you out, you could switch to a V-brake or hang one of these (http://store.icyclesusa.com/cantilever-brake-rear-cable-hanger-black-p5677.aspx?utm_medium=cse&utm_source=googlebase) from the seatpost binder bolt.

BL

[EricEstlund]

Or one of these (http://www.rivbike.com/images/products/full/0000/2478/15-153b.jpg).

[that guy]

Yeah, a hanger that has a way of clamping the straddle cable would be best. That way it will stay where you put it.

[AndrewS]

I have an off-center stop on my Litespeed Obed. With the clamping Shimano straddle it behaves just like it should. No special tension adjustment

I generally prefer clamping straddles. I think it would set up fine with a regular hanger, too.

[sgmidf]

Thanks. I'll look for one of those.

[tuscanyswe]

why would you design an of center stop? wouldent you loose power even if the straddle wire is of the secured type?

[AndrewS]

They did it that way because it is simpler, lighter and routes the cable with fewer kinks.

I don't see where you would lose power to. It isn't greatly off center, and even if one side has less leverage, the other side has more, so it's a wash.

It really isn't a problem at all.

If you really want to scratch your head, look at the relative leverage on a double pivot road caliper. Not only does the right side have more leverage, the left side moves more!

[Mark McM]

If you really want to scratch your head, look at the relative leverage on a double pivot road caliper. Not only does the right side have more leverage, the left side moves more!

If you look closer at the mechanism of a dual pivot brake, you'll see that both arms have roughly the same leverage, and they move roughly the same amount. Unlike a single pivot brake, the arms can't move independently, but are linked together. Specifically, the left arm has a small stub arm (projecting to the right) that is acted on by the left arm. This keeps the arms moving in unison (so that the brakes always stay centered), and transmits some of the force from the right arm to the left arm (making the resultant leverage of each arm nearly equal). This is the reason that dual pivot brakes needs a return spring only on the left arm - due to the linkage, retracting the left arm causes the right arm to retract also.

[AndrewS]

Hey Mark,

I had thought the pin was to help center the brake, but now that you mention it, maybe it also helps even out the leverage as well.

It does seem like the two arms move at slightly different rates. I usually set my brakes fractionally off center so the rim isn't moved right or left when the pads actually contact.

[RFC]

I have this same stop on my 2000 Appalachian. This system was actually intended for V-Brakes, which pull from the side, not centerpulls. The easy fix is to get one of the cheap centerpull cable stops that hangs from the seatpost clamp screw.

[AndrewS]

I have this same stop on my 2000 Appalachian. This system was actually intended for V-Brakes, which pull from the side, not centerpulls. The easy fix is to get one of the cheap centerpull cable stops that hangs from the seatpost clamp screw.
V-brakes don't use cable stops. The housing goes right into the noodle. :confused:

Trust me, Litespeed has been using this set up long before there ever were V-brakes, and they work just fine. I've had one since 1996.

[Cantdog]

Here is a pic. When I squeeze the lever (ergo) it preferentially pulls the right side.

Just looking at it quickly it looks like your tension for each arm is radically different(no tension on the DS arm, and a lot of tension of the NDS arm)

Also, put a wider saddle on there, I've found that a wide saddle mounted closer to the wheel has evened out a lot of my brake centering issues.

[John M]

I'm building up an Litespeed Appalachian frame/fork that I've had for a while and want to use Paul Cantis on it. The rear cable stop on the frame is at an angle. I'll admit I'm no canti expert so I don't see how this would apply force evenly. Am I missing a bracket or some other piece?
Thanks
Steve

If this frame is a size 55 or so, it clearly will not work for you and should be sold to me :)