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Bit spongy earlier and lever slow to return to the normal position. Detected oil leaking which is ok - new olive and insert will cure that.
At the end of the ride the brake as binding when i picked it up to move it, Need a bleed i thought.
Got home and have come to fix it, lever is now stuck in the position as if the brake has been applied. Fitted new insert and olive - bolted back together. Is it that it just needs re-filling with oil from the calliper end to push the piston back to its idle position or does it sound like the lever is broken?
Oh and what diameter tube do i need to bleed these buggers?
[url= http://singletrackmag.com/forum/topic/shimano-xt-m785-bleeding ]Try here for further info[/url]
There is a spring in the lever that should return the blade with or without fluid in it. It sounds like bleeding would not solve your issues. First thing I would check is the piston, from the master cylinder to the lever blade.
Mister p - how do i go about that - is it not a sealed unit?
I mean the silver shaft that goes from the lever into the master cylinder. Look at the lever from the front where the adjuster knob is. Behind the knob there are the bits that push the piston when you pull the lever. I would guess something in there is broken.
I have just this week got my rear XT back from Madison/Chain Reaction following this exact same problem.
Lever went spongey and didnt want to return to the bar fully..
More pronounced at end of clip.
Madison inspected and I got a brand new brake back. Hearing a few reports of this happening lately so it doesn't fill me with much hope for their longevity... 😐
Kayak - mine did that at the start of the ride and then did a "click" and stopped working 🙁
not the original owner so no warranty 🙁
Just been looking - its as if the seal has swollen on the piston head
Right - i have stripped it down into its component level. I have identified the problem as a the seal head. It returns fully 10/11 times but i cannot see how to replace it.
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happened to my xtr brake lever. Got them from germany, took them to LBS who got them replaced by madison, or sram or whoever deals with this stuff
Just been looking - its as if the seal has swollen on the piston head
Thats what I suspected with mine. Has anyone used any lube on their levers post-ride such as GT85/WD40?
I'm thinking perhaps this may be degrading the seals or something. Will avoid from now on but not sure what else to use when the brake gets a caning from the elements...
not used anything on mine
This is an old thread I know, but has only one solved this problem, just had exactly the same issue.
Have taken everything apart, and I'm pretty sure that it's a sticky master cylinder piston.
My brakes are most likely out of warranty.