Binding Brakes

[brucey]

Your collective wisdom is once more required!

I replaced the front & rear pads and ran fresh brake fluid through the systen as part of the overhaul on my 2000 txt 280.

When I changed the pads, I pushed the brake cylinder pistons (all 8 of them!) in and out a number of times to make sure they all operated o.k.

On reassembly with the new pads, I now find both brakes binding. I took the bike for a short test ride to bed the pads in, but they just got hot/worse.

The front seems to have eased off a bit after cooling down but the back brake is still binding badly.

There is less than 0.15 mm between the back of the pads and the back caliper so I'm assuming I need to rub some off the front face of the pads.

Questions are:

Is this normal?

1. How much should I rub off?

2. What's the best way to do this (course wet & dry on a flat surface?)

3. Both brakes arn't exacty sharp considering they are 4 pot calipers. Will this inprove as the pads settle in or do I need to start replacing master cylinders?

Any help appreciated.

Bruce.

[peterb]

Hello Bruce,

These brakes are usually excellent in the dry and don't take much to bed in, normally an hour or so up a stream would be fine.

Maybe you have the front brake lever adjuster too far in and not allowing the master cylinder to return sufficiently. Same for the rear, the brake pedal might need the adjustment backing off a bit to release pressure on the master cylinder.

If they are standard pads, then you shouldn't need to do anything to them at all.

Hope this helps, PeterB.

[brucey]

Thanks for the reply Peter.

A couple of miles up a stream! I live in Hythe, kent. The nearest thing we have to a stream is a 4 ft deep canal or the English Channel!

Both brakes started binding even worse after 5 mins riding up and down the road, although the front wheel spins better now the brake has cooled down. I stopped 'bedding' the brakes in when the bike became hard to push in neutral as they were also becoming hot.

I have to admit I did adjust the master cylinders so there was only a small gap between the levers and the master cylinder push rods.

The new pads are pattern parts and my concern is the almost non existent gap between the back of the pads and the caliper body. This suggests they are maximum thickness.

I'll back off the adjusters and de glase the pads before giving it another go.

My friends 04 TXT Pro has excellent brakes. I just thought mine should be as good if not better as he only has a 2 pot rear caliper.

Bruce.

[biffsgasgas]

If it happens again open up the bleeder to see if your retaining pressure in the caliper. (front or rear)

If you are then your piston (front or rear) is not returning all of the way and opening the compensation port. Back off the adjuster and retry.

If your not retaining pressure then its mechanical and not hydraulic. I am assuming that you removed the rear wheel? Make sure its straight... If its asquew then it will drag on the caliper. Make sure that the front axle and forks are not spread appart as the left fork holds the caliper. Loosen the axle and let the forks relax.

For best performance go for a ride creek mud ect... but just to get them to stop dragging something is up.

--Biff

[scorpa3]

Check that the reservoirs aren't too full! There could be no where for the excess fluid to go thus slightly applying the brakes.

Also check that (as already mentioned) the lever and pedal have some free play.

[brucey]

Thanks guys,

All relavent stuff which I can check.

I'm assuming the 'compensation port' is in the master cylinder as this is the only piston that returns to its start position.

Bruce.

[biffsgasgas]

I'm assuming the 'compensation port' is in the master cylinder as this is the only piston that returns to its start position.

Bruce.

your right on the money Bruce!

--Biff