Make Hydraulic Clutch Pull Easier

[Exbuhe]

Hey guys, I have a KTM 380 with a hydraulic clutch. I replaced the clutch basket, inner hub, and all plates a while back, but the clutch pull has always been really stiff and remains really stiff.

I've been thinking about how to make the pull easier, and the ideas I've had are,

Somehow adjust the surface area of the master/slave pistons to adjust the mechanical advantage

Replace the lever so that the master piston is closer to the hinge point of it = better mechanical advantage?

Or replace the bolts holding the clutch springs in with longer ones (just a bit longer, maybe 50 thousandths each) to reduce the preload on them

I suppose I could also replace the clutch springs with easier ones, but that seems more expensive. So far I'm liking the idea of replacing the clutch spring bolts the most.

I'm running 5wt fork oil in the clutch line, so I don't think that should be the issue, but if it is, let me know.

Thanks in advance for your input, sorry if this should go somewhere else.

Exbuhe

[Home Skillet]

http://www.midwestme.com/

[Trailryder42]

It's my understanding that you can buy different Master cylinder pistons to do what you're wanting.

[Chuck.]

The easiest is changing the master cylinder for one with a smaller piston.

[ickfinger]

Enduro Engineering ez pull lever

[Hans Schmid]

5wt fork oil in the clutch line? No wonder! Replace that with brake fluid.....

[jar944]

5wt fork oil in the clutch line? No wonder! Replace that with brake fluid.....

Someone is going to read that and think you are serious.

It's my understanding that you can buy different Master cylinder pistons to do what you're wanting.

you have to change the entire master cylinder, not the piston

The 380 had a 10.5mm master cylinder, changing to a 9.5 or a 9.0 will make a huge difference

Edited July 8, 2013 by jar944

[Hans Schmid]

Someone is going to read that and think you are serious.

you have to change the entire master cylinder, not the piston

The 380 had a 10.5mm master cylinder, changing to a 9.5 or a 9.0 will make a huge difference

I am serious. I've never heard of running fork oil as clutch fluid. Is there this secret I'm missing? Or is it my brake fluid comment? I run brake fluid through my clutch....

[jar944]

I am serious. I've never heard of running fork oil as clutch fluid. Is there this secret I'm missing? Or is it my brake fluid comment? I run brake fluid through my clutch....

magura clutches are mineral oil (atf/10w40/baby/fork..ect)

brembo clutches are brake fluid

Mix up either one (it will specify on the cover) and you need new all seals.

Edited July 8, 2013 by jar944

[Exbuhe]

Magura blood kept leaking out slowly over time, would have to rebleed it before every ride, but the 5wt oil works beautifully, no leaks and no problems (other than the stiffness)

It was my impression (though I haven't tested) that brake fluid would eat away at the seals, not sure though

I like the idea of changing to the 9.0 master cylinder, but looking on ebay it seems that the assembly would be about $170, is there any reason I can't just lengthen the bolts on the clutch springs?

It looks like the EZ pull levers (MME or EE) get really good reviews, and they are a bit cheaper than changing the master cylinder out, so I may try that.

Looks like MME also offers a chainsaw mount, some of the riding I've done that would have come in handy haha

[Hans Schmid]

magura clutches are mineral oil (atf/10w40/baby/fork..ect)

brembo clutches are brake fluid

Mix up either one (it will specify on the cover) and you need new all seals.

Wouldn't he have a Brembo unit?

[jar944]

Wouldn't he have a Brembo unit?

No

[jar944]

It was my impression (though I haven't tested) that brake fluid would eat away at the seals, not sure though

I like the idea of changing to the 9.0 master cylinder, but looking on ebay it seems that the assembly would be about $170, is there any reason I can't just lengthen the bolts on the clutch springs?

1. Correct.

2. Pick up a used master cylinder from a 04-07 450/525 (9mm)

3. It will slip.

[Exbuhe]

Sweet. Thanks everyone for the input. I'll get a little money together and wait for a good deal on a new master cylinder.