Clutch not fully disengaging

Check clutch master for fluid if bad it would be near empty. Or are you saying it only does this hot?

Well. I have this to. Its allso the engine oil that has more friction on The clutch discs when cold. Heat up the oil and the discs run easier.
But hell, that dont look good. Just cleaned out mine and i thought it was bad.
I would blow out all oil i could. Then press gently on the slave cylinder to get the rest out.
You might even consider changing oil a few times close.

Ye. Til its no black residue.
Slave cylinder is down at the engine. Dno What bike u got. But usually three bolts and a fill/air vent.
Dont vent threw there as with a brake. Thats where you fill the oil. Use a syringe. Its pretty easy. Fill up, then suck some out, up by the handle and continue til theres no bubbles.

You added DOT 5.1 to your clutch. It's supposed to be mineral oil. I don't know about DOT 5.1 but it may F up seals in your clutch. I put mineral in my front brake. Had to rebuild it. I put bling cover on the master it didn't have recommendations of what fluid on cover end result more money out of my pocket.

Yep. Make sure to use the correct oil for clutch and brake as Rainero said. Regarding bleeding the front brake; I gave up and surrendered to my swampy front brake. Known to be difficult to get a perfect bleed. You can tie the front brake lever in full brake position and keep that side high over night. It do help some.

When I got the 390 used the front brake was low not bad but not perfect. Tried bleeding it even tried with line with no high side still no help I gave up. Then after about 6 months it slowly came up now works perfect???? This was off-road when it got better.

Gaah. Brakes! Gotta do mine to. Thnx for The reminder.


U said you only bled with dot 5.1 right? Dno how good it would be even if you now have mineral oil in. But i would never get any brake oil in there, even if some say you can. I would rather use whiskey. (that actually works perfect)
But even so. Dot5.1 ia not even good in the brake system. Says clearly in your manual Never to use this on 09-12 modell.
But Im sure it said in my 06-08 manual to have dot 5.1 in the brake system.
Weird i know. Same components!

What year did you have?

Sry for asking again! Just read for The 3rd time that you had a 2013. Cheerio

Some older Bergs used a Magura min oil system, in 2013 they switched to the Brembo mc that uses brake fluid. Might not be a bad idea to disassemble the MC and thoroughly clean it, and start the flushing process with the mc off the bike so you don't just push any crap in the slave and lines into the mc.

Bleeding can be tough in clutches and brakes. If you have a lot of air trapped in your front brake line or master it can be tough to get out. Sometimes a loop can trap air. Try taking off the master and holding it so the line always goes upward without a loop and have the bleed hole at the very top. Then try the reverse syringe bleed. Also tapping the caliper and/or the master can sometimes get bubbles to release and then go up and out.

Good luck

That explains it! Brembo. I Had no idea since they stopped makin bergs at 2012.

He was correct with adding DOT 4 or 5.1. This is the correct fluid KTM/Husa recommends for the clutch master and system.

Not to steal the thread, but this might be of help for future discussions on fluids.


DOT 5.1 has the highest boiling point of any brake/clutch fluid.
Mineral Oil has no industry standard as it is what it is. Some manufactures like Magura and Shimano like this fluid as they also are a high seller of components in the bicycle industry, Unlike Brembo from the motor racing world where temperature of braking systems are extensively higher than bicycles. Not to put down Magura at all, great components as well and I personally never had a failure with my KTM's.


DOT Fluid

Certainly the most commonly used brake fluid. (with the exception of DOT 5) are made up of a poly-glycol base.

Glycol-based fluids consist of a mixture of ingredients.
A lubricant, such as polythene or polypropylene, to keep parts moving freely, A solvent diluent, usually glycol ether, which determines the fluid's boiling point and viscosity.
A modifier-coupler, which changes the amount of swelling of exposed rubber parts.
Inhibitors, to prevent corrosion and oxidisation.

DOT brake fluid is required to meet strict standards and specifications set out by the Society of Automotive Engineers and the Department of Transportation (DOT) - hence the name. These standards centre around maintaining brake fluid performance in a range of temperatures (high and low) and also specify the minimum boiling temperatures which the fluid manufacturers must adhere to. Thus the reason we don't see mineral oil in automotive applications.


Mineral Oil Boiling Temperatures

This is where Mineral Oil differs greatly from DOT brake fluid.

Unlike DOT fluid, Mineral Oil is hydrophobic and does not absorb moisture from the environment. This means that there are no wet or dry boiling temperatures to worry about, the boiling point stays constant and never drops and this is great other than the facts such as most motorcycles are prone to water.
When any water does enter the brake/clutch system, via seals or microscopic pores in the lines etc., will effectively reduce the boiling point of the whole system to that of water - just 100°C. This is because as the fluid repels any water, it causes it to pool at low points within the system, usually the calliper and or the clutch slave, since water is heavier than brake fluid it will settle at the lowest point. This is worrying because the fluid in the caliper/slave is more susceptible to high temperatures as it's at the end of the brake/clutch system, where the friction is created.

I would never be worried about putting DOT fluid into a mineral oil system ever as long as it was 4 or 5.1. I however would be worried about placing a mineral oil into a DOT system.

I am not sure, but I do think that plain pharmacy mineral oil is different than hydraulic system mineral oil as Magura Blood etc. I do think some special additives are placed in. So be sure not to just hit the local drug store and put that into a mineral oil based system.

Any comments on this from personal use? I always use what the manufacture recommends but know other experiment? Idea's?

I made the mistake of putting mineral oil in the front brake worked great till I took off the master reservoir cover off. The seal got to be all most twice size. Needless to say had to rebuild the hole thing. This was a 2011 Berg.