H2 Clutch Mods

Leo wrote:
If you fit the thinner H1-steelplates all 15 plates will fit. That setup will be able to handle up to 100 RWHP when used with ball bearing/Sytech pusher and good cable with stock springs.
Just make sure all springs are equal length (within 0,5 mm) and strength.

JA-Moo wrote:

h2chris wrote:
I have got 8x new H2 friction plates and 7x new H1 steel plates. I read somewhere that you have to machine a bit off the clutch centre. Has anyone done this mod that can advise please?? I also have got the Sy-tech actuator and proper two stroke gearbox oil. Thanks, Chris. (Ja-Moo, where are you!!)

I machine the .030" off the back of the inner basket "nub" but I have heard some that don't. I like the deeper engagement of the pressure plate myself..........

ojensen3 wrote:
I'm supposed to give my machinist guy the inner clutch hub ( not the clutch Housing with the fingers) and tell him to machine .030 off of where exactly? I can't seem to picture it in my mind. Sorry for being so dense, but I just want to do this once. Also when I get my new clutch parts on monday I'm supposed to soak the friction plates overnite in gearsaver oil . Right?

The "nub"..... on the back of the inner hub, where the shaft goes through. And Yes, soak the plated overnight.


Nigel72IV wrote:
I'm running steels that have been modded with a spiral groove - on both sides, same direction- if you could see from the top both grooves would be pointing in the same direction ( make sense? ) supposed to fling oil out better & less area/same spring = more bite.
A trick from the 750 roundcase & 450 desmo ducati crew - it works, standard springs, barnett fibres. My clutch used to slip - not anymore, but then I'm not making big hp.

H2Rtuner wrote:
Leave the aluminum hub with the aluminum end plate in place, DON'T use the early setup, bead blast the steel separator plates, use the expanders, leave the later aluminum end cap in place, and run a set of Barnett springs.

Don't run Barnett plates, they soak up oils and expand when the clutch is pulled in.

I have found the Barnetts to soak with oil and get thicker when the clutch is pulled released, causing a progressive drag when in gear. If the clutch is held released out of gear, when the gear is engaged, the input shaft is partially loaded and hits into the gear dogs excessively harder than if the clutch was released completely, without drag.

I use either the OEM steel backed friction plates, or ones from Vesrah. Vesrah is a company made up of a number of OEM suppliers. Those plates are good ones.

There are two types of stock coated friction plates, one with a steel center, one with a fibreglass center.

There used to be a company in Washington state that made exellent friction plates, but haven't heard of their plates in years, Metal Frictions. If you have the steel center friction plates, run them, they are more durable than the fibreglass ones.

Whatever you do, get some more clutch spring tension into the clutch. Always readjust the clutch release and cable after any clutch work.

Don't run any engine oils in the transmission, run 80W-90 gear oils, Torco, Sta-Lube, etc.

JA-Moo wrote:
Barnett spring are made for very high HP motor. And 5 springs is usually over kill. I just use 3 for a easier clutch pull. And that's usually more than enough pressure.

And if you do run hypoid oil, there are two types, you need the one that is clutch friendly.

Leo wrote:
When using stronger springs, then use a ball-bearing mushroom-shaped pusher. This is to prevent welding the pushrod when you pull the clutch at high speed (>100 mph).
When machining the back of the inner hub, always check whether the first friction plate still clears the outer basket.

motometal wrote:
I like the extra plate mod, regarding springs...if you need more pressure, in my opinion you are better off shimming the stock rate springs with spark plug washers, then to add Barnett heavy springs, just take measurements and make sure you will not get into coil bind.

I realize many folks have used three of the heavy springs with no problems, however since there is an odd number of springs I don't like the idea of it...seems like it would make the cover plate want to tip and could encourage drag problems.