Have 99 800 XCR / M-10 / V-Force. I've considered changing gear ratios, have no need for speeds in excess of 100mph or so. I decided against it though, with the logic that I don't have the ability of using the power I have on tap now 99.9% of the time. Not enough traction. Yea, it pulls HARD. But the track is spinning. Why make it worse? Install extra studs? Yup that'll help. Now we have a heavier, more highly stressed track. When is enough enough (where does one stop on a trail machine)? Don't get me wrong, I love the power and speed, but this sled is used for hard trail running, will never see a set of timing lights or a radar gun. One of the nice things about this engine is the fact that it will cruise at relatively low and quiet (for a triple anyway) RPM (47-5000 is the norm), If I drop a tooth on top in an attempt to get some extra (again, for what?) low and mid range, I'll also be increasing my cruise Rpm too. To each their own, but clutch kits and gearing on the 800 XCR is overkill in my book, at least for someone not racing, anyway. The other thing one might consider is that the chain tensioner is also going to have more slop to take up, stressing it even more (chain will be running further out of line with the gears)...
Gearing changes will definatly improve your acceleration. There is one problem that the above person mentioned TRACTION. If you can hook it up run 23-41 gears, top speed will be good for about 115 MPH on radar. You will need studs and have to pull the transfer blocks. Accelaration from a 30-50 MPH cruise will drasticly improve. As for the HOT SEAT clutch kit, I am not a big fan of it. You can get much better clutching with other kits. Depending on how much power you push and riding style you may want to try tuning with the following: Yellow EPI primary spring (higher engagement and more load on top) stock try a 52-36 helix and if modded go for a 54-36 A grey polaris secondary spring has amazing backshift (not silver) Depening on how much power you have load the primary in consequence. Stock 60 -62 grams and up depending on torque available. Run a torque arm and check the engine mounts. The XCR does not like to rev, for best results load it up engine should rev 8200-8300 out of the hole and shift out to 8400-8500.
now you may not believe this,but if you want to get good hook up and hard pull through the mid range i would try a light primary spring, i dont know what you have stock? but going to sompthing like a blue or blue/white primery will bring your engagement down and shift harder. try this ,springs are cheep. PS> i have been drag racing for a while now and have discovered new things that work. GOOD LUCK
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