http://www.purelogictuning.com/clutch.html

They claim some pretty huge gains (10-12 MPH in 500 feet)
Anybody try one?

All's I can add to this is that I agree to what they are saying about the secondary spring, however to get 10-12 mph out of this, I doubt it? If they would say 6-7mph mabee and I would try it. I think the best thing to do to the diamond drive is cut the secondary down and run the Polaris belt and clutch from there. Just my opinion.

I ordered one so I guess I'll get my question answered in a month or so.

I picked up on of these kits as well. I'm gonna run it with a cut clutch with the cat 044 and the poo belt.

Rock port, you gonna make it down to the oakland ponds agian for testing this winter?? IF it freezes lol

Hey charlo, you get a chance to test yours yet?

One good run...pulls real well and the backshift is unreal but my RPM's are low (7000-7100 on a 1/2 mile WOT pull). Bought a offset tool and will be making sure clutches are within spec this week-end and might wind the secondary tighter and will try again. So far I am happy with the kit.

7000-7100 is right on for that sled. The 3 guys I know with newer ZR9's all have the secondary kit installed. -045 cat belt.

Sounds good! We are finally gettin snow here in southern ontario, gonna start testing soon. Got some ODS and D&D parts to try out.

Are you running the stock secondary and belt? or gone to the 06 spec?

Sounds good! We are finally gettin snow here in southern ontario, gonna start testing soon. Got some ODS and D&D parts to try out.

Are you running the stock secondary and belt? or gone to the 06 spec?[/b]

Stock secondary and stock (updated) belt. Got to go for another run yesterday after using my new offset tool to line everything up (had to remove two shims from behind the secondary). Worked real well on groomed trails, brother tried it out and was surprised compared to last year. My only concern was a long WOT pull climbing a powder covered fire road. Got to the top and I could smell my belt and my secondary was HOT, couldn't keep my hand on it. This only happened in the powder... belt was slipping but not sure why...worked fine the rest of the day.