A good practice is once your by the bike and done your first checks cockpit, mirrors, lights etc is as you start off check both front and rear brakes are functional.
Thanks for the few positive responses.
I always check before riding and I do pump them after taking them off but this time I got distracted by a neighbor and that was that. Only human you know.
Anyway, it's like the piston in the master cylinder is stuck. It can not pump at all. Had the lever off and it's fine. There is no leaks and nothing has been tampered with...
In all fairness if you were working on the system and caused the problem I can’t see how you are going to get a warranty claim. JJHAir lock?
I've had a problem with my front brake for over 60,000 miles where the brake bites, slows and stops the bike no problem but if you keep pressure on the lever it will come all the way into the bar.
Put a warranty in to my local dealer when the problem first developed and they wanted to change all the discs and pads before they would entertain treating it as a fault, I changed all of the above with Brembo parts but they still wouldn't do anything about it under warranty as they weren't genuine BMW Brembo parts.
Still have that issue to this day but learned to live with it and it's not noticeable enough to show up on the Mot brake test.
I remember the problem started after I was trying to pump out a stuck piston, I heard a pop and the lack of firmness has been there since.
I think there must be a one way seal in the master cylinder which turned back on itself with the pressure of trying to push out the stuck piston and that's my problem.
Unfortunately the Master cylinder is a non serviceable unit so if the fault lies within then you'll need to buy a new master cylinder.
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Thanks for the few positive responses.
I always check before riding and I do pump them after taking them off but this time I got distracted by a neighbor and that was that. Only human you know.
Anyway, it's like the piston in the master cylinder is stuck. It can not pump at all. Had the lever off and it's fine. There is no leaks and nothing has been tampered with...
Air lock?
I've had a problem with my front brake for over 60,000 miles where the brake bites, slows and stops the bike no problem but if you keep pressure on the lever it will come all the way into the bar.
Put a warranty in to my local dealer when the problem first developed and they wanted to change all the discs and pads before they would entertain treating it as a fault, I changed all of the above with Brembo parts but they still wouldn't do anything about it under warranty as they weren't genuine BMW Brembo parts.
Still have that issue to this day but learned to live with it and it's not noticeable enough to show up on the Mot brake test.
I remember the problem started after I was trying to pump out a stuck piston, I heard a pop and the lack of firmness has been there since.
I think there must be a one way seal in the master cylinder which turned back on itself with the pressure of trying to push out the stuck piston and that's my problem.
Unfortunately the Master cylinder is a non serviceable unit so if the fault lies within then you'll need to buy a new master cylinder.
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Air lock?
I've had a problem with my front brake for over 60,000 miles where the brake bites, slows and stops the bike no problem but if you keep pressure on the lever it will come all the way into the bar.
Well according to John Clark Mottorad and the Mot station I use there is nothing wrong with it.not only are you making a great stab at killing yourself, you are endangering the lives of others…. you shouldn't even ride 1/2 a mile to a repair shop at 20mph with this fault
you might have got away with it, but as you know there is a fault and it won't improve, you are being exceedingly reckless. It may fail completely at any point
the mastr cyl or seal needs to be checked out by someone competent. Get off public roads till its sorted.
….very risky,
if it can come back to the bars with light pressure applied its almost always a seal fault.
Could be a pipe bulging under pressure. Might even be a combination of things each contributing to the problem. It needs sorting. JJHNo it needs a lot of force to get it back to the bar.
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depends how strong you are....
go to a BMW showroom find one that's sold and about to leave.... you can get that to the bar easy enough
Do you have very strong hands and wrists?
If the piston has jammed fully in the master cylinder you could try pushing all of the caliper pistons fully into the calipers. Do them in opposing pairs and chock the first pair with a suitable sized block of wood. You may need to use a wood clamp or something to creat enough pressure to push the master cylinder piston back to where it should be. Keep an eye on the master cylinder fluid level.
Then refit everything and pump the brakres without the necessary force to again jam the piston until you have a firm lever.