Rexhardy1

Good afternoon. I current have a Trek 930 and am trying to improve the rear brake. The cable runs along the top tube and through a metal tube before reaching the brakes. There seems to be a lot of friction on the cable due to metal on metal inside the tube. Has anyone got suggestions or a good work around for improving this routing? I understand the reason for the friction but not sure how to correct it, if even possible. Thanks.

Rex

DorkDisk

So BITD the solution was to use a piece of inner liner; the issue is that sometimes the liner does not fit through the curves so experimenting might be necessary. Finding the right stiffness is key. I've often used sections of empty ink tubes of disposable pens when I don't have a liner but some are very soft. That was 25 years ago, maybe pens have changed?

Basically many were meant to be run dry, so the best thing to do is run a polished and die cut cable and lube the brake studs to remove friction. Keep the cables clean and friction free and generally the noodle is not an issue. Don't get a coated cable, as the expensive coating will fray off instantly.

You can also run a cam or a different hanger and route the cable directly into either with continuous housing, or by adding a cable stop to the top tube.

Or switch to V brakes.

Rexhardy1

Thanks, I will try the liner from an ink pen first as I have several of those at my disposal. While I am at it will make sure the cable is nice and clean on that section as I haven’t had it pulled since I have owned the bike. Which BTW is relatively recent as I didn’t buy the bike new.

hokiefyd 

I have a Trek 750 with the same rear cable pipe. I use an inner liner from a linear pull brake noodle, and that works great. There's almost zero friction through this pipe with a good liner. A noodle liner has an enlarged flange on one end, to prevent being pulled through the noodle. Insert this from the REAR of the cable pipe, so the enlarged flange bottoms out against the REAR of the pipe. Cable tension while pulling the brake will want to pull the liner forward, so you want this flange on the rear to prevent the liner from being pulled through.

Rexhardy1

Thanks for the other option. I need to try something because I don’t like the way it is now.

justslow

I have a 1996 Trek 730 and it has no brake cable friction issues, so this is a problem that can be solved. Others will tell you how .

Speedway2

When it's time to replace the cables pick up some teflon coated ones...
https://www.amazon.ca/Aztec-Coated-B.../dp/B000FSSMGG