clydeman

Hello everyone, I posted this question on a different forum but not received any help. I am hoping someone out there has seen this bike or knows the answer to my questions.


Now for my question, the bike originally had cantilever brakes but currently it has V-brakes installed. I would like to install a set of cantilever brakes that I have in my parts bin but I have a question about brake line routing as I have never encountered what I am about to attempt to describe.

On the front of the top tube there is a cable stop for the routing of the rear brake cable, the cable then runs bare towards the rear but there is no cable stop towards the rear of the top tube. What is there is, what seems to me, like a metal cable guide (in the photo it is the piece that has a zip tie running through it securing the brake cable to the frame) that the cable is supposed to be routed through to the rear brakeset. Is the cable supposed to run through this cable guide bare or is there supposed to be some sort of lining inside to prevent metal against metal rub? Am I supposed to have a rear brake hanger as well for the rear brake? It just seems to me that there is supposed to as the one and only bike I owned with cantilever brakes had a hanger.

Thanks for any information and help.

FWIW.... I am not too much money into this bike and that is the only reason I am tinkering with it. Otherwise I would just ride it as is but I have trouble leaving well enough alone.

nfmisso

Stop the normal housing at the stop near the front, run bare cable back to the brake through the cable guide. Use a short length (say 3 to 6 inches) of liner (for example: https://www.amazon.com/Jagwire-Black...ke+cable+liner) thru the cable guide.

I have this on my Trek 720 with Tektro 720 canti brakes.

dsbrantjr

You can skip the liner in the cable guide if you want; it may wear through in a few decades.

Andrew R Stewart 

A linear pull brake noodle usually needs casing at it's upper/feed end. So a true casing stop at that other end of this last loop of casing is also needed. The Mongoose (built and sold many of these BITD) lacks this stop. If you run the inner cable through the curved tunnel/guide without any casing it's likely that the rear brake will suffer from centering issues at the least and maybe lever travel before pad contact ones too. The cable run needs proper cable routing stops for safe/best set up.


The easiest way to get all right is to run full length casing and attach it to the TT with tape/zip ties. Next might be to use the forward TT stop as a cable clip, run housing to it from the lever and also from it back to the noodle. The rear section of this casing will bypass the curved tunnel and need a tie onto the TT for location control.


Next up is to use a clamped on casing stop on the rear of the TT with the casing going to the noodle feed/top end.


Have you also changed the OEM levers to a linear pull spec? Andy.

Jeff Neese

Just run the cable through the guide and down to the brakes. Early '90s Rockhoppers have the exact same thing and it's designed that way - no liner or extra hardware needed.

Andrew R Stewart 

Good point. I obviously miss read the OP and thought he was trying to use linear brakes again. The OEM set up usually had a section of low friction liner running through the curved tunnel. Andy.

clydeman

Gentlemen, thank you all for the information provided. I've decided to, for the most part, leave well enough alone. I'm going to simply dismantle the bike, and lube the headset and bottom bracket. Clean the frame and drivetrain and throw in one of the mentioned frame mounted cable stops to better route the rear cable and call it a day.

I've already tossed out the wheelset that came with it (I replaced the wheelset with a Mavic A319 on Tiagra hubs wheelset I had sitting around for a few years), aside from the wheels using Schraeder valve tubes, there were multiple nipples frozen in place so I wasn't able to get a decent truing of the wells done.

Something I noticed, this bike looks more used than it ever was, I am assuming, based on neglect. The rear cassette looks fine, the chain is the original chain from what I can tell and measured with the Park tool and the ruler method, shows no discernible stretch, the crankset rings look good. I'm thinking of throwing on a new chain even though the one on there looks fine.

New chain, a clamp on cable guide, new cables and housings, wheels and lastly tires and tubes and I'll be done.

Once again, thanks to everyone.