Discussion
After snapping the chain on my Commuter bike I decided to ride my Felt in today but the discs are binding really bad. They were doing this a while back but nothing to serious. However, today when I lifted the front wheel it would stop after half a turn so they are pretty bad now.
I read the manual last time it did this and all it said was to loosen the pads (Avid Juicy 7 with the little red dial on the lever), but this made no difference. Is there a simple fix or is it a LBS visit?
I read the manual last time it did this and all it said was to loosen the pads (Avid Juicy 7 with the little red dial on the lever), but this made no difference. Is there a simple fix or is it a LBS visit?
The 'Pad Contact' adjuster dial on the lever does nothing to the calliper or the pads. What it does, simply, is change the point at which the brake lever acts on the hydraulic fluid. Giving you more 'throw' on the lever.
It sounds like your rotor and calliper are misaligned. This could be either the calliper having moved or the rotor becoming warped.
If the calliper has moved the manual explains how to align it - undo the two fixing bolts, pulll and hold the lever and the tighten the bolts back up.
If the rotor is warped then gentle pull / push it back into shape.
It sounds like your rotor and calliper are misaligned. This could be either the calliper having moved or the rotor becoming warped.
If the calliper has moved the manual explains how to align it - undo the two fixing bolts, pulll and hold the lever and the tighten the bolts back up.
If the rotor is warped then gentle pull / push it back into shape.
Sounds like you have too much fluid in the system. Note the following fix has worked on Hayes and Giant MPH hydraulic brakes. I have no experience with Avids.
1) Remove the wheel of offending brake disc
2) Open the brake fluid reservoir
3) Using a large, flat screwdriver, slowly push the pads back into the calliper a small amount. This will cause some of the brake fluid to come out of the reservoir so have a cloth ready
4) Close the brake fluid reservoir
5) Re-attach wheel
6) Use the dial you mentioned to adjust the bite point and enjoy bind free brakes
You may need to repeat if they're still binding. Make sure you do step 3 a little at a time because if you over do it (push the pistons right back in) you'll need to add more brake fluid.
1) Remove the wheel of offending brake disc
2) Open the brake fluid reservoir
3) Using a large, flat screwdriver, slowly push the pads back into the calliper a small amount. This will cause some of the brake fluid to come out of the reservoir so have a cloth ready
4) Close the brake fluid reservoir
5) Re-attach wheel
6) Use the dial you mentioned to adjust the bite point and enjoy bind free brakes
You may need to repeat if they're still binding. Make sure you do step 3 a little at a time because if you over do it (push the pistons right back in) you'll need to add more brake fluid.
mk1fan said:
The 'Pad Contact' adjuster dial on the lever does nothing to the calliper or the pads. What it does, simply, is change the point at which the brake lever acts on the hydraulic fluid. Giving you more 'throw' on the lever.
I don't know about Avids, but Giant MPH brakes DO move the pads in/out out of the calliper using a dial on the reservoir. Quite a useful feature if you change discs and they're slightly thinner/thicker than the ones fitted before mk1fan said:
The 'Pad Contact' adjuster dial on the lever does nothing to the calliper or the pads. What it does, simply, is change the point at which the brake lever acts on the hydraulic fluid. Giving you more 'throw' on the lever.
It sounds like your rotor and calliper are misaligned. This could be either the calliper having moved or the rotor becoming warped.
If the calliper has moved the manual explains how to align it - undo the two fixing bolts, pulll and hold the lever and the tighten the bolts back up.
If the rotor is warped then gentle pull / push it back into shape.
I think it may be a combination of rotor and fluid It sounds like your rotor and calliper are misaligned. This could be either the calliper having moved or the rotor becoming warped.
If the calliper has moved the manual explains how to align it - undo the two fixing bolts, pulll and hold the lever and the tighten the bolts back up.
If the rotor is warped then gentle pull / push it back into shape.
Reason why, is that after not using the bike for a while the levers felt solid,, also when I put the front brake on it isn't an even brake, it snatches a bit. Looks like I am going to have break a rule and read the manual properly.Also, do I need any special tools which I may not have as not had a bike with discs before.
Edited by lingus75 on Tuesday 19th August 15:18
lingus75 said:
after not using the bike for a while the levers felt solid,, also when I put the front brake on it isn't an even brake, it snatches a bit.
This is exactly what happened to my brother's bike (Giant XTC) which he'd left standing for 6 months of non-use and was resolved with the above method. No special tools needed either Moose. said:
lingus75 said:
after not using the bike for a while the levers felt solid,, also when I put the front brake on it isn't an even brake, it snatches a bit.
This is exactly what happened to my brother's bike (Giant XTC) which he'd left standing for 6 months of non-use and was resolved with the above method. No special tools needed either Moose. said:
I don't know about Avids, but Giant MPH brakes DO move the pads in/out out of the calliper using a dial on the reservoir. Quite a useful feature if you change discs and they're slightly thinner/thicker than the ones fitted before
Avid's Pad Contact Adjuster works as I described. In principle, with new pads and a full system you should need to turn the adjuster 'In' (as marked on the lever) to give throw to the lever. As the pads wear you move the adjuster 'Out' to compensate for the movement of the self adjusting pads.Moose. said:
Sounds like you have too much fluid in the system. Note the following fix has worked on Hayes and Giant MPH hydraulic brakes. I have no experience with Avids.
1) Remove the wheel of offending brake disc
2) Open the brake fluid reservoir
3) Using a large, flat screwdriver, slowly push the pads back into the calliper a small amount. This will cause some of the brake fluid to come out of the reservoir so have a cloth ready
4) Close the brake fluid reservoir
5) Re-attach wheel
6) Use the dial you mentioned to adjust the bite point and enjoy bind free brakes
You may need to repeat if they're still binding. Make sure you do step 3 a little at a time because if you over do it (push the pistons right back in) you'll need to add more brake fluid.
I wouldn't do this on an Avid system as it's really easy to get air into the system. Item 6) won't work - see above.1) Remove the wheel of offending brake disc
2) Open the brake fluid reservoir
3) Using a large, flat screwdriver, slowly push the pads back into the calliper a small amount. This will cause some of the brake fluid to come out of the reservoir so have a cloth ready
4) Close the brake fluid reservoir
5) Re-attach wheel
6) Use the dial you mentioned to adjust the bite point and enjoy bind free brakes
You may need to repeat if they're still binding. Make sure you do step 3 a little at a time because if you over do it (push the pistons right back in) you'll need to add more brake fluid.
Well, that is me confused again. the shop said to release the bleed nipple and let just a couple of drops out as when the bike was built up by them it was Jan and cold.
Now, the bike has been stored in a dry cellar and also covered. They said that as the lever has gone hard and they are binding it is likely to be the warmer temp, and the leaving it standing which has caused this to happen. By releasing a few drops this should sort it.
He didn't say about using a screwdriver to move the pads and it is unlikely I would have done this, but he did say just by releasing the nipple it will let out sufficient fluid to stop the problem.
Regards the dial, well, all I used it for before was to change the bite point of the lever as the shop said this is all it does and has no affect on the pads. So, I guess by releasing a few drops I am letting the pads back of the rotor a bit?
Now, the bike has been stored in a dry cellar and also covered. They said that as the lever has gone hard and they are binding it is likely to be the warmer temp, and the leaving it standing which has caused this to happen. By releasing a few drops this should sort it.
He didn't say about using a screwdriver to move the pads and it is unlikely I would have done this, but he did say just by releasing the nipple it will let out sufficient fluid to stop the problem.
Regards the dial, well, all I used it for before was to change the bite point of the lever as the shop said this is all it does and has no affect on the pads. So, I guess by releasing a few drops I am letting the pads back of the rotor a bit?
You'll need a torx bit allen key / socket, I can't remember what size, and a 4mm allen key.
Using the allen key loosen off the lever from the handlebar and twist the lever to be horizontal.
Turn the Pad Contact Adjuster all the way 'Out' (as marked on the lever).
Loosen off the bleed port screw on top of the lever. Do it slowly until some fluid starts to come out. Don't take it all the way out. Allow a small amount of fluid to escape and then re-tighten up the screw.
Then give the lever a couple of pulls.
Repeat if still 'stuck'.
If you turn the Padd Contact Adjuster screw all the way 'In' (as marked on the lever) it will do the same as the above. If it was all the way 'In' to begin with then the initial brake set-up was poor.
Personally, it sounds like the lever piston seals have dried out and are a bit sticky - this wouldn't give you binding at the wheel though.
Once you've done the above re-align the calliper as described in the manual.
Clean up any spilt fluid with water asap after the bleed port screw has been tightened else your paint will flake off.
Using the allen key loosen off the lever from the handlebar and twist the lever to be horizontal.
Turn the Pad Contact Adjuster all the way 'Out' (as marked on the lever).
Loosen off the bleed port screw on top of the lever. Do it slowly until some fluid starts to come out. Don't take it all the way out. Allow a small amount of fluid to escape and then re-tighten up the screw.
Then give the lever a couple of pulls.
Repeat if still 'stuck'.
If you turn the Padd Contact Adjuster screw all the way 'In' (as marked on the lever) it will do the same as the above. If it was all the way 'In' to begin with then the initial brake set-up was poor.
Personally, it sounds like the lever piston seals have dried out and are a bit sticky - this wouldn't give you binding at the wheel though.
Once you've done the above re-align the calliper as described in the manual.
Clean up any spilt fluid with water asap after the bleed port screw has been tightened else your paint will flake off.
more likely to be one of the three . . .
air in the system - bleed the brakes (a very simple job)
caliper pistons sticking - need cleaning and lubricating (another simple job)
caliper pistons siezed and shagged - replace
take it to your LBS - let them sort it - brakes are kind of the most important part of your bike!
khushy
air in the system - bleed the brakes (a very simple job)
caliper pistons sticking - need cleaning and lubricating (another simple job)
caliper pistons siezed and shagged - replace
take it to your LBS - let them sort it - brakes are kind of the most important part of your bike!
khushy
mk1fan said:
I wouldn't do this on an Avid system as it's really easy to get air into the system. Item 6) won't work - see above.
Fair dos As mentioned, I don't have any experiance with Avids.Thinking about it, the Giant ones just required undoing the bleed nipple which released the excess fluid and didn't require pushing the pads out (which was required on the Hayes).
Well, after thinking about it and visiting Leisure Lakes in Cheltenham I have decided to get them to look at it for the first time, and I will then get the kit needed to do it myself. The main reason is that after a test ride they reckon the seals and pistons may have gunked up a bit. The bike was standing for quite a while so I reckon for the £25 they are going to charge to strip them down clean and bleed them is worth it for the first time.
Thanks for the help though chaps
Thanks for the help though chaps
Well, not that exciting but I thought I would report back. Took it into LBS to have the work done after I had played around with the setup.
I took the advice of resetting the calipers and the rear disc runs sweet now but the front still sticks a bit. The mechanic had a look for me before he took it in and said they do not need bleeding, no fluid needs to be removed and the seals are fine. He said it would be a waste of money to get them to work on it!
He said that I need to ignore the instructions about setting the calipers by holding the brake on and do it all by eye moving it manually. This is how they do it in the workshop, and although it is a pain it's the best way to do it and it’s the only reason why the discs are rubbing.
So, thanks that man! Is 'your brakes need bleeding' the bike equivalent of 'you need new discs and pads mate' from car mechanics?
I took the advice of resetting the calipers and the rear disc runs sweet now but the front still sticks a bit. The mechanic had a look for me before he took it in and said they do not need bleeding, no fluid needs to be removed and the seals are fine. He said it would be a waste of money to get them to work on it!
He said that I need to ignore the instructions about setting the calipers by holding the brake on and do it all by eye moving it manually. This is how they do it in the workshop, and although it is a pain it's the best way to do it and it’s the only reason why the discs are rubbing.
So, thanks that man! Is 'your brakes need bleeding' the bike equivalent of 'you need new discs and pads mate' from car mechanics?
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