After goofing off yesterday I headed out on a ride with Julien around Ken’s loop. Not long into the ride, just before a fast gully descent, I noticed the rear brake didn’t feel right including a forceful click felt through the brake lever towards the end of the action. It turned out one of the pistons had siezed. The brake still sort of worked ok, the other piston making up most of the difference and flexing the rotor sideways in the process. The Hippie Track rides have worked the brakes hard lately, to the point of chronic  fade — leaving its mark on the brakes, literally, with some rotor burn. Wonder if it’s all related.

Rotor burn
Test Track Rotor burn

Heading back home early is never a fun idea so we fanged off down the descent and continued along the ride with the thought in the back of my mind that I should take it easy on the rear brake until I got back home, and use the front brake a little more.

As the ride progressed the front brake lever became softer and softer until there was virtually no front brake left. Hmm… fair amount of mineral oil seeping from a connector, that’s probably not a good sign.  But it did make the last few fast sections of the ride a hoot with only the partial back brake left, sliding retro style!

Then the whole Easter holidays thing sunk in… today’s Easter Saturday, public holidays from now until the following Wednesday. Perfect Autumn weather forecast and I probably didn’t have the bits and pieces to fix the brakes. No ridey ridey until later in the week. NOOO!

Them's the brakes
Them’s the brakes

After spending some quality time with Google this morning things were looking up. My Mountain Unicycles were fitted with Magura HS33 hydraulic brakes so I had mineral oil to spare, along with the bits and pieces to bleed the front brakes, and there were lots of tips online about freeing the piston which apparently is a common gremlin with Shimano SLX and XT brakes.

Empty mineral oil reservoir, that ain't going to help
Empty mineral oil reservoir, that ain’t going to help

An hour or so later the HD was back in action with brakes that feel pretty good. The front must have been leaking oil for some time as it’s got some bite now. The rear pads definitely need replacing soon, but with both pistons working again it’s all cool.

Funny thing is the ONLY thing I don’t like on the Mojo HD are the brakes. I just don’t like the SLX brakes — how they look and how they work (or don’t). I would never have fitted them on the HD, but it came with the SLX brakes and by then there was no spare coin left in the piggy bank. Now I’m looking forward even more to sending these bad boys to the spare parts bin when $ allow.

Them’s the brakes 😛

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