www.boxertrix.com

Spoke to amate about Gs911 and it’s to cycle the abs pump so bleeding with ignition off would mean abs valves are closed so should be ok. He also had a similar problem albeit with a different BMW and after refurbishing the master cylinder it was OK. Fingers crossed

The only other thing I can think of, other than everything discussed so far, is that there could be an internal deterioration in the hydraulic lines from master cylinder to the callipers (and ABS unit).
I had it on a car once and the inside of the flexible pipe bore had deteriorated and a flap of hose was sealing the returning fluid to the master cylinder so the pistons and pads did not return into the calliper fully. This left them rubbing after the first application and heated up the disc which then warped.
Maybe a set of new brake lines would be the last resort.

Hope you get it sorted.

SP250 wrote:The only other thing I can think of, other than everything discussed so far, is that there could be an internal deterioration in the hydraulic lines from master cylinder to the callipers (and ABS unit).
I had it on a car once and the inside of the flexible pipe bore had deteriorated and a flap of hose was sealing the returning fluid to the master cylinder so the pistons and pads did not return into the calliper fully. This left them rubbing after the first application and heated up the disc which then warped.
Maybe a set of new brake lines would be the last resort.

Hope you get it sorted.

This was similar circumstances to my mate except it was the seal on the master cylinder piston. A re build kit for the 12s isn't listed but there could be for other bikes with the same size piston (as was the case with my mates and that solved the problem)

Fingers crossed. Good call about the brake lines though. Shame there are 4 of them . I will of course report back on any progress and thanks for the thoughts and input all.

Took the bike out for a run yesterday to see what the replacement master cylinder has done and it would seem that it may have worked! Ran the bike around for an hour taking in some normal and hard braking situations giving the new discs time to cool between and bed in a bit. Stopped a few times to feel the discs and although hot, not excessively so. Got the bike back and put it on the stands to try the front wheel and it spun with little resistance as would normally be expected so fingers crossed that these discs won't warp.
Only time will tell but I expect to rack up a bit of mileage over the next few weeks so will keep you posted. At least there may be light at the end of the tunnel instead of a man with a torch. A long, expensive, frustrating time may be coming to a close.

Have you pulled the old one apart to see if there appears to have been a problem with it? Would be interesting to know

Not yet, just wanted to make sure the new one was working ok. The replacement does not have the bleed screw at the top that the old one had so may be from a newer model. The bike is having new tyres fitted today so will ride it a bit more and then pull the old one apart with photos

Humbug wrote:Will do. I need to get to the bottom of this issue. Love the bike as the 100,000 miles proves but its difficult getting the most out of it on the track days and touring without proper braking at the front end. Cost is now becoming an issue due to the residual value of the bike (about thruppence ha'penny now!)

New bikes are not entirely inexpensive


Chris

Humbug wrote:Took the bike out for a run yesterday to see what the replacement master cylinder has done and it would seem that it may have worked! Ran the bike around for an hour taking in some normal and hard braking situations giving the new discs time to cool between and bed in a bit. Stopped a few times to feel the discs and although hot, not excessively so. Got the bike back and put it on the stands to try the front wheel and it spun with little resistance as would normally be expected so fingers crossed that these discs won't warp.
Only time will tell but I expect to rack up a bit of mileage over the next few weeks so will keep you posted. At least there may be light at the end of the tunnel instead of a man with a torch. A long, expensive, frustrating time may be coming to a close.

That's great news, fingers all crossed that this is the end of that frustrating period for you

200 miles today and no issues so far!! Woo Hoo

Humbug wrote:200 miles today and no issues so far!! Woo Hoo

Get in there

That sounds really promising,well endured! You will still be para about it for another couple of hundred miles , then it will be just a memory.

Great news

Chris

Thanks for all the ideas and thoughts chaps, this is what a forum is about. I'll let you know how it all goes. Just had some Pirelli Angel GT2 fitted and they seem really planted. Supposed to be excellent in the rain and seemed fine yesterday down Snake Pass in the damp drizzle.

MOT passed today with no issues at all. He even commented that the front brakes were perfect now and he couldn't feel the slight pulsing that was present last time. Woo Hoo!!!