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Rear V Brake Pads P-38

I did not see a search function here, so here goes.
I need to replace brakes on my P-38. The front V-Brake Pads fit fine, but the rear pads will not fit in between the rim and chain stays.
If I squeeze them in there, there is no movement for the pads to open away from the rim.
The pads currently on are paper thin so I cannot tell if previous owner shaved these to work/fit.
My thoughts tell me to either look for the pads where the stud is off center with a short and longer pad side or to go with shorter road brake pads.
Anyone else have a suggestion or solution for this?

1) I have not heard of P-38 riders having this problem before. Others have sometimes had the chain rub against the top of the drive-side V-brake arm with certain combinations of frame size and rear cassette. This can be annoying. The P-38 was originally designed before the mountain bike boom and the popularity of cantilever and V-style brakes. The early bikes used road bike calipers.
2) What rear wheel rim are you using? Specifically, how W-I-D-E is the rim externally?
3) What V-brakes are you presently using?

Without knowing more, my first guess is that you have an unusually wide rear rim on your bike. But that is just a guess. Please tell us more, and maybe we can help some.

Safe riding,
Joel

Thanks for the reply.
I measured the rim width at 23mm so not excessively wide. This is a 700c wheel and there is not a lot of distance between the rim and chainstay.
This is a 1994 model if I remember correctly, could this have been originally setup for a 26" wheel with the canti studs for 700c brazed on later?
It does have the cross tube if front of the rear tire with a hole for a brake caliper to mount and it does looked spaced somewhat right for a 700c wheel.
The V brakes that came with the bike when I bought it were the Shimano BR-M600 DX brakes. The pads are thin and possibly done this way to get them to fit.
I put XT Brakes on it as I had them here and dimensions are close and does not look like it is the brakes themselves that are causing the issue.
Even with the brake arms off the bike, it is difficult to put a brake pad between the rim and chainstay and without clearance, the brake pad cannot open to clear the rim.

Hi again jth-

You are right: 23mm external width is not unusually wide. It is more of a medium width rim, so it should fit without any brake pad clearance problems against the chain stays. It is hard to diagnose and treat bike problems over the net without being able to eyeball the bike and play around with it. So I can't help you fix the problem. It could not hurt to get on the phone with Tim Brummer at Lightning. If you know a recumbent friendly bike mechanic, taking the bike to the local expert would be best. Some bike mechanics hate anything unusual or unfamiliar, but others relish the prospect of figuring out a solution to a problem they have never encountered before.

Some people have put mountain bike rear wheels on P-38 bikes with various ways of kludging the brakes. I have done this myself in order to use fatter tires than are possible with the standard 700C rear wheel. But there should be room for using V-style brakes with the normal 700C wheel.

Sorry I could not help more. If you manage to get the problem sorted out one way or another, please write back and tell us what was going on, and how it got fixed.

Safe riding,
Joel

I took your advice and called Tim at Lightning. He told me that at about the age of my bike they switched from caliper brakes to V-Brakes and the canti studs could have been added some time later.
His suggestions were to relieve or crimp the chainstay tube to make clearance for these brake pads, to sand the brake pads so they fit or to go back to a caliper brake.
The bike was just repainted, so I am not going to mess with crimping a relief in the chainstay tube. I do not really like this idea anyways.
I am not planning on sanding the new pads either. The caliper brake may be the way to go but with less stopping power.
This bike is an XL and even though the caliper might work well with my 160 pound body weight, it may not do well with a larger person weighing 100 pounds more should the bike not stay with me.
I will need to find an alternative, an off center type of pad or make an adapter so the pads are above or below the chainstay and this tube does not interfere with the brake operation..

My inclination would be to try a dual pivot caliper brake, using the existing brake bridge. Most of your stopping power comes from the front brake anyway. If your front brake is functioning properly, having a rear brake that is not quite as powerful as the front should not handicap you. With a good quality cable and cable housing, and with careful cable routing, you should be able to get decent braking on the rear.

I agree with you about not wanting to crimp the frame tubes to make more room for the V-brake. That just rubs me the wrong way with an expensive and carefully made bike frame, and it will hurt the resale value of the bike if you decide you want to sell it.

Good luck,
Joel

Tim at Lightning also commented about not needing a lot of brake from the rear brake.
I do like the V brakes on this bike as at some point they upgraded to stronger braking for a reason.
Then again, there are a lot of road bikes out there, have been for years, using rear caliper brakes to stop.

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