Sunday, November 6, 2011

Twice Bitten.

I love my XTR Trail (M988) brakes. They are true one-finger brakes. Great power AND modulation. Now... Shimano's hoses... I have no use for. My original hoses leaked. I replaced them with stock Shimano hoses. They leaked too. Same failure mode, as well. I could warranty these through Shimano. But... Since I'd rather ride my bike, than work on my bike, I cut my losses and went a different direction this time.

The failure occurs right here.


The crimp between the banjo fitting and the hose. It isn't a huge catastrophic leak. More of a seep. But it contaminates the pads. Braking power goes away, and they squeal. Left long enough the lever will get low. I didn't let it go on that long this time.

Off with the Shimano hose.


And on with a Goodridge replacement hose. The Goodridge #107 kit is listed as compatible with the older version XTR brakes (M-966/965). Those brakes used two banjo fittings. The Goodridge catalog does not list any kit as compatible with the newer M-985/988 XTR Brakes. But, the kit includes both two banjos and a straght fitting, and it should fit.

The fittings are of excellent quality. I've used Goodridge hoses on race cars before, so that was expected.


These are neat. Miniature Aeroquip fittings! If you've ever built up Aeroquip hoses, installing the hoses is a cinch. If not... it's still a easy. Here is how it goes. Start by trimming back the outer casing, but not the braid.


Use a sharp blade. The casing is tough. Push the outer fitting on, and make sure the ends are clean, square, and fully inserted.


I threaded the male fitting into the master cylinder to hold it. You can do this in a vice, too. But remember, the fitting doesn't swivel, so you'll have to turn the fitting with the hose anyway. The threaded end simply goes into the hose side fitting into the center of the hose. Screw it on until the fitting flows onto the shoulder of the outer fitting, and snug it with a spanner.


Tada! A nice tight fitting.


Next route the hose. Cut it to length. And repeat with a banjo fitting on the caliper end. Now since the kit isn't specifically designed for M-985/988 XTR brakes, you have to re-use the stock thru-bolt in the banjo fitting. Works just fine. Don't forget the O-rings.


You can use an allen wrench or the like to clock the fitting in the correct orientation. Then snug the fittings.


Repeat for the rear brake. Bleed the air out (worst part of the job) and that's it.

Also keep in mind the Goodridge fittings are reusable if for some reason you need to replace hoses. They can be tightened if they leak, unlike the Shimano factory crimps. Leak free. But so were the Shimano at the start! If these also leak... it's me! Hope this helps, because leaky XTR hosese seems common.