1992 GT - First restoration and a lot of missing parts

[jaychen]

Well, Ozpete was kind enough to send me the missing brake components! That sorted that out, but I have hit another big road block.

Hoping someone here can share a trick/tip to get this sorted but im expecting the worst.

The rear brake runs inside the top tube and something is blocking the cable sheath somewhere directly in the middle of the top tube...

any ideas on how to unblock it?

 

[Gtpulse]

Well, Ozpete was kind enough to send me the missing brake components! That sorted that out, but I have hit another big road block.

Hoping someone here can share a trick/tip to get this sorted but im expecting the worst.

The rear brake runs inside the top tube and something is blocking the cable sheath somewhere directly in the middle of the top tube...

any ideas on how to unblock it?

A good squirt of WD40 in the orifice let it soak then try and clear with some welding wire or garden wire possibly even coat hanger wire if you have one thin enough. Try from both ends

 

[jaychen]

A good squirt of WD40 in the orifice let it soak then try and clear with some welding wire or garden wire possibly even coat hanger wire if you have one thin enough. Try from both ends

Have done the WD40 and tried to clear with some 1.6mm filler rod. It is rock solid and didnt budge at all in there and the other end is totally blocked. Was talking to a mate who is a gun at welding, he said I can definitely weld a 2mm drill bit (cut down to about 10mm overall length) to the end of a length of brake cable. Was thinking of using the brake cable to try and drill it out, but obviously that will only work if it's something soft. If it's old brake cable jammed in there it's not going to touch it.

 

[zetecmk2]

keep at it, you won't scrap this project over a blockage. love it!

 

[jaychen]

Well, i welded a 2.5mm drill bit to the end of a brake cable today and tried to drill it out. No luck. Couldnt get enough force on the cable to really get anywhere. Whatever is in there is hard.

I think the tube had a liner which has melted from the powdercoating.

Next step - going to heat up some 2.4mm stainless filler rod till its red hot and try to push it through the plastic, melting it, bit by bit. I could just weld on brake cable stoppers (not sure what they're called) but I want to have the rear brake run through the top tube.

Not going to lie, was close to throwing in the towel a few times after this recent lot of problems.

 

[RetroDavy]

Great project and nice paint: keep going!

Your melted tubing theory sounds plausible. Whatever the cause, googling 'replace brake liner inside frame tube' threw up a range of webpages so I expect someone has dealt with a similar issue before.

Resolving these problems is part of the satisfaction (for me anyway, but maybe that's just odd).

 

[Gtpulse]

The melted liner does sound like the culprit. The last bike I had this issue on was an early Xizang, that one I think was a squished cable ferrule stuck in there PITA.

It sounds like you are more than capable in the improvisation department. A step back and a cup of tea always help in this situation!

 

[ozpete]

Hi,

Try using a section of car speedo cable inner if you can find some thin enough. At least you can put a bit of force behind it as it wont compress or deform like welding wire when drilling.
Or an arc welding rod in a suitably hard grade (crack off the flux), and a bit of rigorous tappage from a hammer? I really hope this turns out OK for you!