Hello,
Out for a long spin yesterday. At some point I noticed fluid on the rt side storage comp. cover.
looks wet under reservoir.
Brake had been ''stiff'' on return for a while.
Is it likely to be seals ?
how do I go about fixing it ?

ta
Rod

First I'd try and pinch-up the banjo-bolt on the underside (the hose connection to the master cylinder). Clean-up the area and see if the leak persists.

However, as you say that the lever is stiff the most likely thing is that the seals in the piston are failing.

A repair kit isn't expensive. Best thing is to drain the fluid from the front entirely and then replace the piston and seals because the fluid will most likely be contaminated by the old seals. You can just draw the fluid out of the master cylinder with a syringe, have plenty of tissues handy to mop up what comes out when you strip the old piston out, then once the new one is in place, bleed the brakes but given that it's a safety issue, I'd go for the full fluid replacement.

Very good Mike,
I'll give it a go during the week.
Will have a good look first , but prety sure its the seals.

more anon

R

DeRodster wrote:...., but prety sure its the seals.

more anon

R

 of course but:
problems with the hydraulic are a result of

- dirt
- age
- old brake fluid
- ignoration

the repair sets are ailable for the magura pumps
but often you only have a 50:50 chance that it works

i do not repair the pumps anymore
1x new pump incl all tubes new and your brakes will do it for ages

if you open/change the pump: be shure that when remounted
the pressure pin (pos 7) gets locide !!
i didn´t do that once - no fun at all

The 20mm master cylinder (16V K's and K1100) seal usually goes away because the outer boot perishes first which allows debris to wear the M/C's inner seal. Of course, age and/or a lack of regular maintenance (brake fluid flushes) can have an affect. They're an easy one to fix with a modicum of mechanical skill. Most of the R1100 Oilheads use the same part number master cylinder and kit.

This is the kit for that sort of cylinder: 32 72 2 332 037, about $87.00 at US dealerships, and the outer boot is part number 32 72 2 310 756 and costs about $8.00... They're numbers 20 and 8 in the above parts illustration.

The 'Bins boys sell the piston kit only, part No.23960, for £25.00 ex VAT and the boot, part No.23990, for £3.50 ex VAT.