Hi all,

I have developed a leak in the clutch on my 2009 duke, most likely a slave cylinder issue. It is going to be covered by warranty but I can't get it sorted for the next 2 weeks. I have 2 main questions.

What kind of mineral oil can I put into the clutch? The only oil I can find in Dublin is this Shamura mineral hydraulic oil but it says brake oil on it nothing about clutches. Is this suitable? http://www.halfords.ie/cycling/bike-par ... -bleed-kit
Also I have no idea what is currently used in the bike, the garage told me just to use normal brake and clutch oil, maybe that's the reason I have a leak in the first place! Is it ok to mix the new oil in or should I drain the system? The reservoir is already empty so there may be air in the system now.

Second, if i top up the fluid as needed can I drive the bike for the next 2 weeks without causing any damage to the bike?

Cheers all!

If you're not sure what's in there, then you're better off draining the old and replacing it with all new fluid. But if you're slave is cooked then this would be a waste of your time anyway.

I've only ever used Motorex Hydraulic 75 as recommended because it's always been available at my LBS. Someone with more experience on the matter may be along to add what other products you could use. I wouldn't be confident with that bicycle brake fluid though.

Total LHM or from another brand. It's a mineral oil used in Citroen. Same stuff as magura or morotex at a fraction of the price.
Bleed all the old stuff out properly and be done with it.
The slaves develop leaks, if you want it fixed properly get an Oberon slave and it'll be fine forever. You'll have to pay for it but I don't think you're bike will be off the road for 2 weeks.

I was just browsing the workshop manual and noticed that the clutch hydraulics have to use (and I quote): "SAE 10 BIODEGRADABLE HYDRAULIC OIL ONLY" I don't have any leaks from the slave cylinder (he says...) but was wondering why KTM explicitly state not to use brake fluid in the clutch system. I can only surmise that it's due to an incompatibility issue between seals and regular brake fluid, maybe this is the cause of so many slave cylinder leaks; following people changing the fluid and doing the natural thing and using brake fluid like you would on pretty much any other bike (or car for that matter, though I'm happy to be corrected on that).
Is the oft-quoted Oberon replacement slave cylinder compatible with brake fluid?