Brakes sticking when hot/stationary

[RossObey01]

Afternoon all,

I went for a great ride across Dartmoor last week but unfortunately got caught in some traffic when I got to Exeter. I was filtering where possible but spent a fair amount of time sitting in traffic so the engine was getting pretty warm, not to mention it was also a very warm day.

I noticed when sitting in traffic that there seemed to be some binding on the brakes and it wasn't easy to rock the bike back and forwards, when rolling to a stop it was evident something was slowing the bike slowly.

Traffic cleared got up to speed and the engine cool, when I got to the next set of lights it was fine, as it has been since.

I'm certain I wasn't catching the rear brake with my toe but other than that I can't think of what might have been causing it?

Just thought, it could be a warped disk which would explain why I only noticed it one or twice? You can hear light rubbing on the pads when wheeling the bike around but as far as I'm concerned that's normal, I've never noticed any binding when wheeling it around before.

[Mr Gazza]

If there is not enough free play in the rear brake lever it can bind sometimes.

Old fluid makes it worse and heat sets it off.

So two thing you can do...First is cheapest, just back off the lever stop a little.
Second is to change the fluid.

It doesn't indicate a warped disc.

[RossObey01]

Fluid is less than 6 months old and plenty of free-play! I'll look at backing it off slightly but don't think that's the problem. Thanks though, Gazza.

[Mr Gazza]

No point changing the fluid then.

Manual states 1.5 to 2mm of freeplay at the stop, but to be honest I run it at about 3mm to be on the safe side having had the bind up problem to the point of total lock up on my very first ride out on the bike....My fault though, I had adjusted it up with too little play.

My MOT tester also noticed on one occasion, that the brake was not fully releasing after applying...There were one or two turns of the wheel before it let go properly.

I never did really find out what the problem was, but I exersized the pistons a bit by pushing them back and working the brake a few times...Whether that did the trick or not, I don't really know but the brake is fine now.

If it binds again when you are out, hop off if you can and see if the free play has been taken up.

[RossObey01]

I was thinking about this again last week and realised when checking the free play I completely ignored the rear brake. Sure enough, when I checked it, there was none. Loosened the lock nut off, gave the rod a quick spin and hey-presto, a good amount of free play.

I've not experienced it since, but I've only been out once and it wasn't as hot as before, so fingers crossed that was the problem!