Brake Levers Crushing Knuckles?!

commencal

Hi, hope someone can help with this....

I run Avid Juicy 3 brakes which have been great for the 6 months I've had them but since recently having the pads changed I've noticed the levers have become really loose. When braking, the levers actually touch the backs of my knuckles to a point that I can no longer brake hard if I need to without crushing my own fingers!

I asked my local bike shop if they could tighten them but I was told it wasn't possible - instead I should try putting elastic bands around the levers overnight in the hope that this would help them reset.....

Has anyone else had this problem? Is there any truth in what I was told? Or is there a more conventional method to tighten them up?

V confused! Thanks for any help!

nicklouse

who changed the pads?

how do the levers feel compared to before?

have you adjusted the lever reach adjust to move the levers out?

RideTheLakes

Bleeding them should help. You can get an Avid bleed kit from CRC for about £20 and Avid brakes generally need an occasional bleed anyway.

commencal

Levers were fine when new but gradually started to feel a little looser over time. I (possibly naively) assumed they'd feel better once the pads were changed. Bike shop changed the pads and ever since the levers just feel like they're getting looser and looser.

I haven't adjusted anything on them as I happened to ask about what to do while in my local bike shop and was just plain confused by the response I got - haven't dared touch them as a result! Would moving the levers out help though? I only have small hands (I'm a v petite girl) so only just reach my levers as it is - the problem is simply that they now move inwards too far!

Thanks

nicklouse

Ok so nothing has ever been done to the brakes except for the pad change.and they are now worse than they were with the old pads in?

And the pads were changed buy your LBS.
if this is correct then i feel that the LBS had a spot of bother with changing the pads and something went wrong.

Or

If i read things correctly there is a lot of movement in the lever before the pads touch the disc? So it could be that the pistons just need to settle down again. now this can be aided by pumping the levers and then tying them back to the grips over night.

this just does what a few good rides do.but this may not be possible.

have the brakes had time to settle since the new pads were fitted?

If yes it may be time to check the lever reach. the reach screw is on the inside of the lever assy and is a 2mm allen headed adjuster.

commencal

RideTheLakes wrote:

Bleeding them should help. You can get an Avid bleed kit from CRC for about £20 and Avid brakes generally need an occasional bleed anyway.

Thanks, perhaps that's what they need then. I'll check out CRC......

commencal

Nicklouse, thanks for your reply.

First, I was actually watching when the pads were changed (bit of a freebie lesson so I can do it myself next time!) and although they were a bit fiddly, nothing seemed to 'go wrong'.

So, second, yes you're right, there is a lot of movement in the levers before the pads contact the discs. I have used my bike a fair bit since the pads were changed though so perhaps I should skip the 'pumping and tying back' approach and move straight on to adjusting the levers?

RideTheLakes wrote:

Bleeding them should help. You can get an Avid bleed kit from CRC for about £20 and Avid brakes generally need an occasional bleed anyway.

'RideTheLakes' suggested bleeding them (see above) - should I consider that too?

Thanks

nicklouse

if there has benn nothing lese don to the barkes then a bleed is not needed.

and you say

there is a lot of movement in the levers before the pads contact the discs

bleeding will not solve this.

It is mechanical and where the pistons are now sitting.

first things. pump up the levers and tie them off tonight and see if it settles the pistons closer to the pads.

If not then the pistons can be moved closer to the disc by removing the wheel and gently pumping the lever BUT most people end up with a piston poping out of the caliper meaning new pads and a bleed.

So tie the lever back and see. if not adjust the reach and i am sure that in a while you will be able to adjust them back when the piston have moved closer to the disc.

commencal

Cool, I'll get the old girl out of the shed tonight then and give that a go. Do I need to tie them back pretty tight or just at biting point?

Thanks for your help, much appreciated!

nicklouse

just so that the pads are touching the disc on both sides. but pump the lever first to make sure they are nicely in contact.

commencal

Fab.

Thanks again

tjm

Nick might be right but there are a few other things to try.
Before I start I should say I have no experience of Avid brakes, only Hope. However, I hope all this is pretty generic....

There are a number of reasons why you could get excessive movement at the lever.
1) The lever is just adjusted too close to the bars the start with.
2) There is air in the system. the air has to compress before it does any useful braking - hence the long travel.
3) A fault in the master cylinder (brake lever). Depending on the master cylinder type this can mean the lever treavel is excessive. It can also mean the lever will slowly move to the bars when held on.
4) Stuck piston in the caliper.
5) Pads damaged or just need bedding in properly.
6) Misaligned caliper.
7) bent disc.

Most of these are unlikely (which is probably why no one else has mentioned them) but it is worth going through them all just in case as most are easily checked.

So, starting with the easy ones....
1). Lever adjustment: You say you have small hands so I guess it is pretty close to the bar already. Is it still where it was before or is the off position now closer. Unlikely to be this or I think you would have noticed. However, if it is, a simple reach adjustment would solve it. If it is not, then I suspect reach adjustment might mask the problem but not solve it - and make reaching the lever difficult which you don't want!
6) the caliper should be aligned fine as it used to work. however it might have moved or been bashed. Are the bolts tight? Is there an even gap front and back between the caliper and the disc. If not, you need to refer to the manual on alignment- I think it is pretty easy on the Avids.
7) Bent disc - if the disc is bent it will push the pads back too far - creating excessive movement. Ideally, when you spin the wheel there should be no noticeable wobble in the disc. Also with this a few pumps of the lever should get short travel which should not change if you leave it. however, if you then spin the wheel the pads are pushed back and the long travel returns.
4) have a look at the pads when operating the brake. Do both sides move roughly the same mount? If one pad does not move and you can see the other bending the disc accross to meet it then you might have a stuck piston.
In this case, try gentle pushing the disc towards the stuck piston to push it back into the caliper. Operate the brake again - does it move back out again? If it does, then it might be that it just needs centering. Push the disc accross towards the "good" side to push the pad in there. then operate the brake again - this should centre the pads. On my hopes I have to do this occasionally, no obvious reason why. Sometimes I have to hold the disc across to the "good" side while operating the brake a few times to allow the lazy piston to pump out.
5) maybe, but you said it was getting bad before the pads were changed and is still getting worse. So that sounds unlikely.
3) Unlikely. I've only ever seen this on car systems. Assuming the lever doesn't slowly sink to the bar when applying constant pressure then it is probably ok.
2) Air in the system - This gives a generally spongy feel and long travel. Nick appears to have discounted this as nothing has been done to cause it. I agree this is logical but I have heard others say their system needed a bleed for not obvious reason. if all else fails I would give it a go. I'd be tempted to ask a bike shop to do it 1st time round. It is easy enough to do but it is also easy enough to make things worse. (at least it is on my hopes and all the car systems i have done)
tying the lever to the bar overnight helps with bleeding as it helps the air bubbles come together but strictly speaking it should not be necessary. having said that I had to do that to my rear brake to get it from ok to perfect.

Sorry about the essay, the causes already mentioned are the most likely but it is worth checking all the rest as it is easy enough to do. Oh, and it I got anything wrong I am sure someone will tell me!

Oh, and out of interest, how much movement is there at the end of the lever? That might give us an idea of how bad the problem is.

notfast

i've been having this problem with my hayes nines. My lbs said it would be at least a week and a half before they could even fit me in , so i have decided to give it a go myself, bought new pads and fresh brake fluid. I have got to the point where i have a good bite point while the brake lever resevoir is parralel to the ground but once i move the lever to the correct position fr riding the bite point disapears and i ruin my knuckles.
Anyone have any idea why this is happening?
cheers
Wes

tjm

nicklouse wrote:

if there has benn nothing lese don to the barkes then a bleed is not needed.

and you say

there is a lot of movement in the levers before the pads contact the discs

bleeding will not solve this.

It is mechanical and where the pistons are now sitting.

I missed this bit- might have saved typing that essay1
On my hopes there is a spring holding the pads apart. When there is air in the hose there is indeed a lot of movement in the lever before the pads move. I know this because I have just stripped and rebled them and had exactly that last night :-)
Are the avids different in this respect?

nicklouse

notfast wrote:

i've been having this problem with my hayes nines. My lbs said it would be at least a week and a half before they could even fit me in , so i have decided to give it a go myself, bought new pads and fresh brake fluid. I have got to the point where i have a good bite point while the brake lever resevoir is parralel to the ground but once i move the lever to the correct position fr riding the bite point disapears and i ruin my knuckles.
Anyone have any idea why this is happening?
cheers
Wes

yes you still have air in the system.

nicklouse

tjm wrote:

Are the avids different in this respect?

yes no and maybe. the spring is not there to keep the pads apart it is there to reduce the rattle.
the pistons in the brakes are retracted by the seals and brakes that have the spring use it to keep the pads in contact with the pistons. No more that contact or they could push the pistons back into the caliper ruining the feel of the brakes.


Just changing the pads on a untouched braking system that worked fine will never need a bleed.

If the brakes have been bleed or have had a leak then there may be too much fluid in the system or if a leak some air. both these will need sorting.

tjm

yes no and maybe. the spring is not there to keep the pads apart it is there to reduce the rattle.
the pistons in the brakes are retracted by the seals and brakes that have the spring use it to keep the pads in contact with the pistons. No more that contact or they could push the pistons back into the caliper ruining the feel of the brakes.

good point. I knew that honest! Must be old age..... :oops:

Just changing the pads on a untouched braking system that worked fine will never need a bleed.

I think that is where we are interpreting things differently. I read it that it was getting bad before the pads were changed, just that changing the pads did not solve the problem (but didn't cause it either).
So I still reckon there is a chance that air is causing the problem - although I can't say what let it in the system.

If the brakes have been bleed or have had a leak then there may be too much fluid in the system or if a leak some air. both these will need sorting.

fair enough.