Shorten XT Brake Hose Problem

iLukeKendall

I'm currently in the process of shortening the brake hoses for my new Shimano XT hydraulic disc brakes.

They came pre-bled, and I've followed these instructions from Shimano, suggesting how to trim the line without needing to re-bleed them: http://www.shimano.com/publish/content/ ... le.html/02)%20Brake%20Hose%20Trimming.pdf

I've cut and re-inserted the hose, and have used a tyre lever to reset the pistons, however they don't seem to want to fully return inside the calliper - they will sit fairly flush, but then they eventually push themselves back out again.

Is there any way to get them to fully reseat? I read someone else's forum about trimming brake cables and they had to remove some mineral oil from the reservoir - could this be the case here? If so, how would be the best way to go about doing so?

Also, if I didn't bring the callipers out so far, would this problem not happen? I still have to trim the rear one!

Many thanks.

nicklouse

Did you release the bleed nipple on the lever assy as you pushed the pistons home. Catch any fluid.

iLukeKendall

I didn't no... the instructions didn't tell me to! If I release it now, will fluid come out and solve the issue?

iLukeKendall

Okay, so I released the bleed nipple on the lever, and some oil did spill out, with more coming out whilst forcing back the pistons. This did allow me to get the pistons to reset and to get the rotor back in, so thanks for the suggestion!

The brake still seems to function well, although I think the lever might feel a little more 'mushy' now than it did before. I think I'll ride with it for a bit and order a bleed kit if I really notice a difference.

Giraffoto

This was my experience of the no-bleed method - it works very well, and if you use the official Shimano funnel, it's very clean.

iLukeKendall

Just done the rear brake this afternoon. Followed the same procedure as suggested by Shimano, and a bit of oil leaked/came out, however the brake still seems to function very well. Whilst they're not perfect, I don't think they're crying out for a bleed right away, so I think I'll give it a few rides and see how I get on!

I was pretty worried about cutting the cables at first but turns out it was pretty easy after all, and now I don't have a stupid mess of cable in the cockpit!

danchandler

I shortened the hose on my deore using a random PDF guide off t'web, but it's the same as shimano's method. I didn't release the screw on top of the master cylinder, and mine came out fine, in fact its rock solid. Must have fluked it