P-85 Clutch Setup

i have a 91 indy rxl650, runs awsome. i want to get a little more power out of it, so i am. going to rebuild the primary and secondary clutch. here is what i got now... 10am(47.5) weights and a rusted blue primary spring. 35/21 gears which i think are stock. i was thinking of going to a 20 tooth top sprocket and im not sure if i should go to a 62 pitch chain or will the stock 64 work with moving in the tensioner more. also i was wondering about getting 10m weights (49) with a new blue spring. just wondering what everyone thought about this.

i have a 91 indy rxl650, runs awsome. i want to get a little more power out of it, so i am. going to rebuild the primary and secondary clutch. here is what i got now... 10am(47.5) weights and a rusted blue primary spring. 35/21 gears which i think are stock. i was thinking of going to a 20 tooth top sprocket and im not sure if i should go to a 62 pitch chain or will the stock 64 work with moving in the tensioner more. also i was wondering about getting 10m weights (49) with a new blue spring. just wondering what everyone thought about this.
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I would leave the gears alone. Start by replacing the stock spring with a new one and then try it out. One thing at a time is the rule here. What is it that you are looking for anyways?

try the new spring first. the old rusted one may have taken a set.

the 49 gram weights will slow shift rpm down.

need more rpm, use lighter flyweights,
need less rpm, use heavier flyweights.

your primary clutch is rpm sensitive and you can make it turn the rpm you want and need by adjusting the weight of the flyweights.

first, use a spring that gives you the shift speed you want. then if you need to,adjust the weight of the flyweights.

Uncle Neil has it cased. Key is one thing at a time for sure. When you say power and as you talk about gearing I presume you want some bottom end. I like to go down a gear or two and use a helix with two angles. I like to finish with the same angle as the stock helix. Lots of bottom end power, pulls really hard. You loose some top end speed but you sure get there quick! As far as your chain goes you don't want it too tight but you don't want to have a ton of slack for the tensioner to adjust, straighter the better. Your gearing is fine I would say, 1.6 ratio, otherwise you would have a 1.75, little much how 'bout going to 36 from 35 which takes you to 1.71 . Good luck!