Author Topic: Cable disc brakes  (Read 1946 times)

Re: Cable disc brakes
« Reply #25 on: June 01, 2019, 10:19:10 pm »
well done!   You seem to have (somehow) avoided the worst of any corrosion that might have occurred. The parts that need grease include the thrust bearings and the ramp bearings; you shouldn't add to much because it may migrate to the pads with inevitable results.  The grease both  lubricates and (hopefully) inhibits corrosion. Unfortunately it also mixes with pad wear debris and (over time) turns into an abrasive sludge, hence you ought to repeat the caliper overhaul at intervals, either every set of pads or every other set of pads seems about right.

The pad adjuster screw threads can be retapped and (ideally) new screws fitted if you can get them; IIRC they are a standard M-series thread. I have used a few turns of PTFE tape in place of blue (paste type) threadlock on these screws. If you use nothing at all then they tend to adjust themselves as you ride.

If you manage to rebuild the old caliper to GWO then I'd suggest that you can rotate the three calipers around whenever you change pads, and aim to usually have a freshly cleaned/rebuilt caliper (with good pads in it) ready to go.

cheers

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Cable disc brakes
« Reply #26 on: June 01, 2019, 11:10:33 pm »
I'd be interested to know how you get on with rebuilding the caliper, as I have one with the same problem (one pad adjuster bolt "seized"). I haven't got around to it for about a year or more...
A cup of tea is the perfect bridge between real life and cake.

quixoticgeek

  • Mostly Harmless
Re: Cable disc brakes
« Reply #27 on: June 04, 2019, 12:12:16 am »

It seems that the thread on one of the pad adjust bolts was buggered. The outbound one (black).

Hadn't realised the two bolts are different, and not interchangeable. I don't know if it was buggered before I disassembled it, or was buggered in situ.

Have ordered 2 new sets.

Reassembly isn't too bad, apart from when you come to try and get the big arm thingy on. It has next to no flex, and getting it refitted involves a moderate amount of swearing, and if you're not careful, blood sacrifice.



Left is the rear caliper, fresh off the bike. Right is the cleaned and serviced front caliper, minus one pad adjust screw.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Cable disc brakes
« Reply #28 on: June 06, 2019, 09:10:42 am »
that looks more like it!

I found Spyke/Spyre calipers (unnecessarily) awkward to reassemble; it didn't feel quite right to be bending the main brake arm like that, but it seems it is the only way.  BB7 is easier to strip down for sure.

In what way is the pad adjuster screw wrecked?  Is the thread in the piston OK?

cheers

Re: Cable disc brakes
« Reply #29 on: June 08, 2019, 02:29:45 pm »
Just fitted some cantillevers... I doubt if I 'll ever do that again. Mind you, reading the above it looks like moving to discs is jumping from the frying pan to the fire.  Perhaps we should have stopped at V brakes.

Mind you, looking forward to a bike with hydraulic discs.

Cudzoziemiec

  • Solar powered, tea fuelled cycle-wol
Re: Cable disc brakes
« Reply #30 on: June 09, 2019, 01:19:53 pm »
I've never fitted cantis, but IME Vs are harder to set up (more fiddly) than either cable discs or sidepulls/dual pivots. I expect this depends a lot on your personal fiddle factor though.
A cup of tea is the perfect bridge between real life and cake.

Kim

  • Timelord
Re: Cable disc brakes
« Reply #31 on: June 09, 2019, 04:12:42 pm »
Agreed.  Vs work well, but there are so many degrees of freedom in a single adjustment that it's inherently fiddly, and quite easy to do badly.  Give me cable discs any day: similar performance, lower fiddle-factor, and they work properly in the wet.
Careful, Kim. Your sarcasm's showing...

Re: Cable disc brakes
« Reply #32 on: October 29, 2019, 06:36:08 pm »
I have TRP's on the Trice XL.
When I first looked at them they only had one pad adjuster in each caliper, so I ordered and fitted new ones.

Then couldn't get them to fit over the disc, even when they were adjusted right off!

So I stripped them, pretty clean inside but dry!
Cleaned lubed and re-assembled.

Still didn't fit so I took them apart again and compared them to one I have on another trike, everything looked the same & measured the same using Vernier's.

This time after I Assembled them, they FITTED!!! Yaay, whoo hoo!
(I still don't know why they wouldn't as everything was the same).

I have just stripped, cleaned & re-lubed them today ready for winter and they fit first time. ;D

I like them because they don't distort the disc when used as a parking brake and left on for days at a time.
Unlike the BB7 that was fitted as a parking brake by ICE it made a zing,zing,zing noise after being left on overnight where the disc had warped!


ElyDave

  • Royal and Ancient Polar Bear Society member 263583
Re: Cable disc brakes
« Reply #33 on: October 29, 2019, 07:57:08 pm »
my BB7s have a habit of doing that if not quite adjusted right, or the rear which can intermittenrly fail to return to "off" as the arm catches the rear rack
“Procrastination is the thief of time, collar him.” –Charles Dickens