Setting up mechanical disc brakes

father_jack

Just bought a Carrera Gryphon, thought MTB has more disc brake owners so posted here. I understand how disc brakes work, but never set one up, except for adjusting the inner brake cable so you get enough braking force. However either I get rubbing or not enough power once you slacken off the cable. I know you can adjust the rotors, but is there a video for Tektro IO disc brakes?

How many bolts are on the caliper (and where?) to make adjustment? What is the procedure, do I move each side equally, say 1mm gap for each side?

The Rookie

I think the Tektro IO are dual adjust (my daughter has a set at home) if so....

Wind cable adjuster all the way into the lever housing, loosen cable clamp on the calliper, allow cable to settle and retighten.

Slowly adjust both pads (inner and outer) in until they are just touching the disc, loosen calliper to adapter brackets, pull lever to align calliper to disc and while holding the lever progressively re-tighten the mounting bolts, then adjust the now 'square' pads in until just starting to rub - sorted.

I never use the cable adjuster on the lever on my Gryphon (although it uses Clarks callipers) pad wear is so slow you just tweak the pad adjustment when the lever goes a bit long.

EDIT - dual adjust link to manual for the similar Auriga's here http://www.tektro.com/_english/01_produ ... rt=1&fid=1

Simon

tsenior

simon has it but a tidy trick i used to use was to insert 2 clean business cards (1 either side) between the pads and disk then fully wind pads in, before tightening the mounting bolts, this keeps everything square and you dont have to hold the lever in.

father_jack

hmmm a video would make it easier.

tsenior

i dare say there will be one on t'interweb somewhere

by the way with disk brakes a minor amount of rub when first setting up is acceptable. then go out and bed them in by riding at speed down a steep hill single brake stop, repeat, repeat, repeat until rotors hot enough to steam. then do the other.

unixnerd

I had these on my Saracen. They were fine at first but once the pads started to wear down they were useless. There's a real knack to adjusting them properly.

You need to ensure that when you pull the brake lever the arm on the caliper is moving enough to engage the pads forcefully into engagement. I had to slacked the bolt holding the cable to the caliper arm, pre-load the lever a bit then tighten the bolt.

It's also vital to ensure you turn the allen key on the stationary side of the caliper enough to position that pad correctly. It's easy to badly set them up so that when you brake the disc is deflected and wears the pads at an angle (which causes more problems if you try and adjust them later).

More modern cable operated discs move both sides, like hydraulic brakes do. Far better.

father_jack

Having problems setting these up.

supersonic

What problems are you having?

nicklouse

http://www.tektro.com/_english/03_suppo ... 548315.pdf

fairly simple. nothing different to most mech. brakes.

but without knowing where you are having issues it is hard to say what to do.

some rubbing is expected until bedded in. evey time you move/adjust the caliper you will need to bed the pads in again.

father_jack

ok managed to set it up, pretty lousy compared to V brakes, bit disappointed. I've set the caliper as close as possible.

When I squeeze the brake lever, the rotor is pushed wheelside, is this ok?

Doesn't seem to have enough cable pull for decent braking, no braking is applied for the first 1cm on the brake lever.

supersonic

The whole design is supposed to deflect the rotor. 1cm free lever travel sounds around average for any brake.

You can pull cable through the cable bolt on the actuator arm or use the barrel adjuster on the brake lever.

Let them bed in too.

father_jack

actually around 2cm and nothing happens.

Guess pretty expensive to buy a whole hydraulic disc set? considering the bike was £240..
won't change them for a while though.

nicklouse

Father Jack wrote:

ok managed to set it up, pretty lousy compared to V brakes, bit disappointed. I've set the caliper as close as possible.

When I squeeze the brake lever, the rotor is pushed wheelside, is this ok?

Doesn't seem to have enough cable pull for decent braking, no braking is applied for the first 1cm on the brake lever.

it should be move a little. use the adjuster to move the pad to the rotor. as this will reduce the rotor movement.

father_jack

move moved it close as possible.

The Rookie

I have to say the 1.0's on the 2 bike's I've ridden with them had nowhere near the 'bite' of the BB5's on the lads 'new' Spesh.

If the lever travel is too long then the pads aren't adjusted close enough.

Never use excessive preload (well pretravel) on the lever arm, it changes the operating point on the internal cam/balls and affects the braking power available. make sure each pad (that is 2 per end) are wound out until they are just starting to rub, if the lever travel is too long them its having to move the pads too far - simples*! My Clarks on my Gryphon (well Gryphon frame - nothing else is original) use less about 1cm lever travel.

*Assuming someone hasn't put non linear levers on which pullless cable for the lever travel!

Simon

father_jack

How do you move the left pad without touching the swing arm? Like you do with the stationary side.

It's better, but seems worse than long reach calipers, what I did was press the lever hard, use my other hand to grab the wheel. I could turn it, after a bit of force. Then tried it on the road bike with calipers and much harder to rotate the wheel.

The Rookie

Aplogies, the 1.0 is single adjust, did you follow the instructions linked to by Nick?

If that isn't working for you I would suggest you loosen the calliper mounting bolts and cable clamp and then wind out the static pad adjuster until the disc is just rubbing both sides then tighten the mounting bolts and cable clamp, the control lever side will rub a little bit for a short time.

Simon

father_jack

You mean move the whole caliper as much as possible to the left? I thought of that, since the left pad isn't adjustable.

Dissapointed, getting more braking power on my long reach calipers...and being this bike cost £240 replacing them with BB7 or Juicy Avid 3.5's will cost 50% of the bike #

also don't like brake levers, how the end cap fits in, my old brakes went into a gap, so the only way they can come loose is to pull them about half a inch towards the end of the lever. No way would plop out of the hole. However these Tektro brakes on the whole is exactly where the clamp is, I can see it may plop out, and once is enough.

The Rookie

No move the calliper as far to the right as possible, moving unadjustable left pad closer to the disc.

Simon

nicklouse

The Beginner wrote:

No move the calliper as far to the right as possible, moving unadjustable left pad closer to the disc.

Simon

looking from which end of the bike?

the inner one is adjustable but static while the outer moves in operation.

father_jack

right moved calipers to the right as possible, then adjusted the wheel sided pad. So close can hardly see light through the pad. No rubbing.

And still seems rubbish. :roll: No feeling until at least half, and pressing hard whilst moving wheel by hand is still not as good as the calipers.

supersonic

What brake levers are you using?

father_jack

Supplied Tektro's. Spent some time moving calipers about, front doesn't pulse anymore. Still bad, know they need to bed in just hope they get a lot better. btw for idea of power can't do a skid (not you shouldn't but gives a idea it doesn't have power to lock the wheels up)

father_jack

ok ordered BB7's, can I use the already fitted 160mm rotors from the Tektro's?

supersonic

I'd get some Avid Speed Dial levers too.

father_jack

yeah got FR7's. All under 100 quid!