Lowering engagement rpm on EFM clutch?

[Sceep]

My clutch takes to high a RPM to engage, and freewheels almost dangerously after rear wheel lockup. It needs to engage at a lower RPM.

I talked to Gary at EFM and he said to shim the clutch pack up to .050-.060 clearance.

I did that. I still want it to engage lower. I shimmed it up to .030" clearance. no change.

So knowing what I do of rekluse z-start clutches (the EFM is similar in construction) and their tuning (which is very little mind you), I know that a lighter spring will lower the engagement RPM.

Heres where i get lost.
The Rekluse uses a spring similar to this for engagement pressure.

the EFM uses multiple stacks of single wave washers like these

so how do i make the single wave washers softer? Remove 1 of them from each stack? flip one in each stack so they are stacked like this (( instead of this () ? order different thickness or material washers and swap them out?

Any help appreciated.

Thanks.

 

[Motosportz]

Call Gary again. I would think remove one but don't know.

 

[Joe Chod]

remove 1 washer from every other for start
if more then do the remaining.

 

[Kyle Tarry]

Are the washers stacked in mirror pairs (like ()()()()() ) or in an oriented pile (like (((((((( )?

There are two effects that matter, rate and preload. Removing washer springs will reduce preload, but depending on the stack it can increase or decrease rate.

 

[tunp]

My recall is to remove the ( washers to increase engagment, or add a ball ( i think)

 

[mtbdoc]

I am running 4 balls in mine, and it almost engages a bit too low. Gary is a great guy. I bought my bike (slightly) used and the clutch locked as soon as it went in gear; when I took it apart, some of the springs were bent. We talked on the phone and he said to mail it to him. He went through it, replaced the springs, and mailed it back...didn't even charge me postage. He told me that people were generally running three or four balls. If you think about it, few balls have to spin faster to lock up the clutch. You probably have three balls in and that is the issue.

 

[Sceep]

I am running 4 balls in mine, and it almost engages a bit too low. Gary is a great guy. I bought my bike (slightly) used and the clutch locked as soon as it went in gear; when I took it apart, some of the springs were bent. We talked on the phone and he said to mail it to him. He went through it, replaced the springs, and mailed it back...didn't even charge me postage. He told me that people were generally running three or four balls. If you think about it, few balls have to spin faster to lock up the clutch. You probably have three balls in and that is the issue.

my clutch has like 20 balls. and they are all in there.

I've gotten used to it but would still like a bit lower. I broke my ribs last week so im out for awhile. i should tear into it while im down in case i need to send it to him.

 

[bigmo]

There are two styles of engagement - you may want to experiment with increasing the ball weight too. Does Gary have access to some slightly heavier balls? You can order some tungsten carbide bearings and experiment yourself - just make sure your weight is balanced out. The tungsten carbide will weight twice that of the stainless and will provide significantly more clamping pressure once the initial engagement occurs.

I know we are mixing apples and oranges here - but when fine tuning my Rekluse, I always found the higher RPM with a solid ball-centric hit was awesome. I sure as heck wish Rekluse would make a 2.0 or 3.0 version for more Husky models. The 2.0 I have on my YZ is so stunningly awesome it is hard to explain. Talk about a killer design!