I have an 08 xtr and the front brakes suddenly have no feel, the lever takes very little effort to apply the brakes and they are slightly grabbing. I have flushed and replaced the fluid and the slides appear to be free, I recently replaced the pads and the Pistons pushed back easily at the time. Does anyone have any suggestions on what to do or has anyone had this issue also? Any help or advice is greatly appreciated.
Cheers Richo

What pads are you using? Are they heavily sintered? When you say brakes, do you mean both front and rear are doing the same thing? Did it happen straight after the flush, refill and new pads?

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Only the front are tight, I've done approximately 1000ks since replacing the front pads which are standard ferodo pads and not heavily sintered. They started to become tight about 150ks ago half way through a fairly long off road ride. I did lay the bike over during the ride but there does not appear to be any damage and the rotor and Caliper appear to be straight. I flushed the fluid yesterday to see if this helped but still no change, It feels as if the brakes have been bled too well if that makes sense.

Well the piston sounds like it's moving freely so we'll ignore that for now.

It's possible the sliders may have started to stick so might want greasing up. possibly you may have some corrosion on the pad pin which could be holding the pads.

another possibility is the master cylinder may be ready for a rebuild, and finally how is the fluid level? there's a chance there could be to much fluid and you've got pressure in your system.

Blind shooting. Is it possible, after that off road trip, that somehow brake lever is the culprit? As non native English speaker I didn't understand description fully. Maybe is a stupid answer.

If it isn't the pads, or the sliding parts then it can only be a hydraulic pressure issue - it cannot be released fully as fluid can't return to the master cylinder.

As a few people have mentioned, first check the master cylinder isn't over-filled.

The next thing to consider (and its quite easily done) is that in the process of changing the fluid and bleeding the system you've turn the master cylinder seal inside out, or dislodged it allowing fluid to pass out but restricting its return.

Lastly, and this is quite rare, the hose might be breaking down internally and allowing fluid to pass only one way. I've come across this three times, twice on bikes, and the last time only a month ago after changing the clutch on my Land Rover...

I replaced the master cylinder and slave cylinder along with the clutch only to find (with everything set up right) I couldn't get any free play and the clutch slipped all the time. Fluid was moving under pressure to the slave cylinder but not returning to the master cylinder keeping pressure on the clutch release bearing. Very similar symptoms to your brakes, but with a hydraulic clutch. Changed the flexi-hose and all was good.

What happened was the hose had broken up inside leaving a flap of rubber partially blocking the bore. This flap acts like a one-way valve stopping fluid returning to the master cylinder. Sometimes you get this and the "flappy" bit works one way, sometimes the other and sometimes blocks the hose completely.

Are your hoses original? You are aware you're supposed to replace them every 3-4 years for exactly this reason.

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Hi pals, me again. Despite some of the good suggestions here, according the chronology, I am a little bit suspicious. Hydraulic lock after 850 km...

not seen it on many modern bikes but plenty on older bikes. maybe the piston seals have started to pop out.

Sorry for the super late reply, I took the m/cal apart and there was a tiny bit of grit blocking the comp hole in the cylinder not allowing fluid to return, quick blow out with air and reassembled and good as new.