ANyone have any advice on clutching my 99 ZR500 sled. It's a stock motor, only problem the clutches both came off a 1997 ZL440. That's clutching for a 68 hp piston port engine, with a EPI clutch kit, on a 96 HP, reed valve 500. It has 10M5 weights in the primary, but I have no idea the angles on the helix. EPI secret I guess. ANy ideas on how to make it work? It has a low rpm bog the way it is. It rips once it gets revved up over 6500 rpm.

ANyone have any advice on clutching my 99 ZR500 sled. It's a stock motor, only problem the clutches both came off a 1997 ZL440. That's clutching for a 68 hp piston port engine, with a EPI clutch kit, on a 96 HP, reed valve 500. It has 10M5 weights in the primary, but I have no idea the angles on the helix. EPI secret I guess. ANy ideas on how to make it work? It has a low rpm bog the way it is. It rips once it gets revved up over 6500 rpm.
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what rpm does it engage at and what color springs are in the primary and secondary clutches? post info and ill try to help :firecats rule:

ANyone have any advice on clutching my 99 ZR500 sled. It's a stock motor, only problem the clutches both came off a 1997 ZL440. That's clutching for a 68 hp piston port engine, with a EPI clutch kit, on a 96 HP, reed valve 500. It has 10M5 weights in the primary, but I have no idea the angles on the helix. EPI secret I guess. ANy ideas on how to make it work? It has a low rpm bog the way it is. It rips once it gets revved up over 6500 rpm.
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A stock 500 has a 51 degree cam, a yellow spring in the secondary and 46.5 gram wts and a yellow white spring in the drive clutch. You also need to know the max engine rpm and stay at or below that. If you over rev the motor your losing power. Your stock clutch engagement is 4800rpm and your stock engine max rpm should be 8500-8700 rpm. Use these as your starting point or base line and check to see where you are at now.

I've been searching for clutching help for a week to find that info!

mine's a 99' ZR500efi. I can only assume stock clutches. (4,000 miles on sled- I just bought it)

Now that i know what it's SUPPOSED to do, I have somethign to compare mine to.

Something I don't get though: I have learned a lot about clutching by reading old posts for a week to get the theory behind them etc. Problem is, I seem to see clutching for engagement and max rpm but for some reason my "bog" is in the midrange. It is very sluggish to backshift but is also slow to upshift.

I was also reading about gearing. Once I get the clutching figured out, I'd like to play gear down a bit too. Most of what I read says stock gearing is almost always too high as protection in case of a top end lake-type run. Since we never get top end runs for any distance around here, I'l love a little more snap. I read about pitch, etc. I see one tooth size allows use of the stock chain. (Smaller top or bigger bottom)

Dumb question (yeah...another one...) do I just count the teeth or are the gears stamped? I still have the stock gears and chain from my 96 ZR580. would those be higher or lower? would they even fit?

Anyone ever play with a ZR500? Most of what I read was all 600 and up sled tuning.