Quick question about brake lever play

portland_bill

My front brake lever seems to have about 15mm of play before I feel any braking as opposed to my rear brake which has about 5mm of play.

Do I just need to add some brake fluid to the front brake or should I try something else?

High-Tower

What brakes are you using?

Assuming the front brake used to be the same as the back one, what's changed? Adding fluid shouldn't be needed unless some has leaked out. Pull hard on the lever and look at the whole brake sytem for fluid leaks. Have you recently tried to bleed the brakes?

It could be that the piston/s have partially seized in the front caliper and are not retracting properly.

bennett_346

As your front pads are worn more than the back, there will be more movement in the lever before the pads bite due to the self adjusting calipers.

Once it gets to the stage where you can't bear it pop new pads in and it'll feel the same as the back again.

High-Tower

bennett_346 wrote:

As your front pads are worn more than the back, there will be more movement in the lever before the pads bite due to the self adjusting calipers.

Once it gets to the stage where you can't bear it pop new pads in and it'll feel the same as the back again.

Surely self adjusting pistons are supposed to prevent exactly the symptoms the OP describes?

bennett_346

High-Tower wrote:

bennett_346 wrote:

As your front pads are worn more than the back, there will be more movement in the lever before the pads bite due to the self adjusting calipers.

Once it gets to the stage where you can't bear it pop new pads in and it'll feel the same as the back again.

Surely self adjusting pistons are supposed to prevent exactly the symptoms the OP describes?

Don't ask me how it works, i have no idea!

portland_bill

Sorry for the lack of info guys.

Hayes Stroker Ryde brakes and it's not long since I changed the pads in the front brakes. I've not seen any trace of fluid anywhere and I've never so much as opened the reservoirs on either brakes so I can't see why the fluid would be any different between the front and back.

bennett_346

The brakes ive had have always been self adjusting but always had more lever throw as the pads wore. If your brakes are slightly underfilled the effectiveness of the self adjustment may be limited.

I think.

High-Tower

Okay, I'm not as familiar with Hayes as some other brakes, but if you've recently changed the pads, it could just be that the self adjusting pistons haven't set properly, although that's unlikely. If you've pumped the lever a few times after the pad change they should be ok.

Did you check that both pistons were free and cleanin the caliper when you had the pads out, it could well be a sticky piston?If dirt or corrosion have affected the pistons and you forced them back into the calipers they will stick against the seals.

With the pads out if one piston moves before the other (likely) you can hold it back and gently squeeze the lever to make sure the other piston moves. Squeeze the lever to ease both pistons out of the caliper. Be careful not to force the pistons too far out of the caliper for obvious reasons. With both pistons eased out get busy in there with some brake cleaner and a stiff brush. Put a small amount of red rubber grease on the piston sides before you push them back into the caliper. Small being the operative word here, you really don't want grease on your rotors or pads. Refit the pads and wheel and see how the brake feels

The Rookie

Watch the pads, do they move at all during the 'dead' part of the lever travel? If so that is your issue, a good way to sort that (sometimes) is to elastic band the lever to the bars overnight (or as long as you can) to encourage them to stay out and not retract too far when you release the lever.

If the disc is warped at all it will knock the pads back as it rotates causing the problem and a straight disc is the answer.

Some setups are poor for this, some use adjusters (like Giant MPH) to manually adjust it out. A seized piston would have the opposite effect (it wouldn't retract) so high-tower is 180 degrees out with his advice on that.

Simon

portland_bill

Well, I had a bit of a play around with it last night and took the caliber off and although both pads were moving, one was certainly more hesitant than the other so I removed the pads and used a long Allen key to hold the more mobile piston down while pumping the lever to push the other piston out and did as you say, brake cleaner and a touch of red grease around the wall of the piston before pushing it back down. I couldn't do more without dismantling the caliper which I just didn't have time for as the bike is now on it's way to Forest of Dean where I will meet it on Friday evening. But anyway, I digress, after doing the same with the other piston and getting a more even movement on the pistons when braking it did seem to remove a little of the play but it's still different to the back brake.

There is every chance it has always been like that though and it's only because I've been on nothing but my roadie since July last year that I'm noticing it now. I'll break the calipers open next week when I get back and give them a proper clean out and service before I engage in the season proper.

nicklouse

Adjust the reach screw/adjuster. And take suitable ools on the ride as it will come right and will need readjusting.

High-Tower

I might be pointing out the obvious, but as you said earlier you've never even had the reservoirs off, I might not.
If you split the calipers you will need to be able to bleed the brakes.

portland_bill

Sorry I'm used to bleeding motorcycle brakes by filling the reservoirs and pumping through. I just watched a couple of view on Hayes brakes and get the setup now.

I'll order a bleed kit and get that done next week.

As for the reach adjusters, they're already wound in coz my fingers are pretty short so I need them pretty close.