I am having a problem and cant figure out what is causing it. It's a FE 390 2010 model, stock clutch, rotella oil, the hydraulic parts have been bled, back bled, forced bled, first with magura oil, then trans fluid. The bike has 900ish miles on it, oil change every ride, filters every other. The clutch works perfect until it gets hot, the bike, not just the clutch, then the lever goes all the way to the bar and the clutch wont disengage. So first I changed the hydro fluid, bleed the oil, magura fluid, back bleed it, no air bubbles. Run the bike get it hot, same thing happens, replace the magura with trans fluid, same thing. I have a friend who has the same problem on a ktm 450 he is working on in his shop, so he changes the whole hydraulic system from another bike, same thing still happens. So then he replaces the complete clutch, fibers, springs and metals, still does it. So the way I see it, something is pushing the piston back in the slave cylinder, as long as I keep pressure on the lever, or work it back and forth, it works fine, but the second I take my hand off the lever, it goes to the bar and wont release! Even sitting still when the engine get hot it will do it, at normal operating temp, say riding down a road, the clutch works great. When it disappears I have to pump up the lever and it will come back for a few seconds, but let it go and it goes away. Could this be an engine oil pressure problem? something is pushing the clutch piston back, but why only when it gets hot? and by hot I'm not talking boiling over hot, just when I'm really getting on it. Help, this has caused some rib breakage!
Help Support Husaberg:
Check your crank case ventilation tube for a kink or obstruction. An over pressurized crankcase can push on the slave cylinder thus driving the fluid back up to the reservoir; resulting in a clutch that must be pumped back up before it will disengage.
I did not think it was possible till it happened to me. Hope this is your easy fix.
Todd
I did not think it was possible till it happened to me. Hope this is your easy fix.
Todd
Bike FE390 2011 EU specs
I had exactly the same problem at 42 hours 1200 km. The clutch would not disengage when engine is hot and resistance at lever would drop to zero. When I let her cool down for a while the clutch would start functioning again although with an inconsistent lever free play. There wes no loss of hydraulic fluid or air in the system. I replaced the slave cylinder, blled the system and the problem is soved 100%. I am a bit puzzeled as to why the clutch failed in the first place since no apparent oil leak was present. I have also read somewhere, that obstruction in the crankcase breather hose could cause a preasure biuld up taht may push the slave piston back, which I doubt. There is spring behind the piston, that in my opinion is strodng enough to overcome the blow by gas preasure.
I had exactly the same problem at 42 hours 1200 km. The clutch would not disengage when engine is hot and resistance at lever would drop to zero. When I let her cool down for a while the clutch would start functioning again although with an inconsistent lever free play. There wes no loss of hydraulic fluid or air in the system. I replaced the slave cylinder, blled the system and the problem is soved 100%. I am a bit puzzeled as to why the clutch failed in the first place since no apparent oil leak was present. I have also read somewhere, that obstruction in the crankcase breather hose could cause a preasure biuld up taht may push the slave piston back, which I doubt. There is spring behind the piston, that in my opinion is strodng enough to overcome the blow by gas preasure.
You'd be surprised at how much pressure that rotating crank can create in the bottom end. That pressure has to go somewhere. I've had my clutch work great until the engine gets to high RPM's then the clutch would disappear until I pumped the lever back up. Cleared the crankcase vent and all was good. This was on a KTM 450 XC.
Similar threads
Register CTA
Register on Husaberg Forum! This sidebar will go away, and you will see fewer ads.
Sign Up
