Ok I have a 2018 Arctic Cat M8 162 235lb with all gear sled is only pulling 7800-7900-7950 sled has 560miles all stock setup other than it has a MVM belt drive. And a can. It’s go 70gr Weights. Stock black spring 120/235 Driven clutch all stock. Any thoughts on getting rpm up? Looking at dropping weight on weights. From 70gr to next lower. Any help be great thank you.
RPM
- Thread starter 2xturbo
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i notice you are in utah, same as me....you don't mention where you are riding, but for sake of a starting place, most of utah riding where you are climbing is above 8k and frequently in the 9/10.5 k altitude range....cats are set up from the factory in the 7-9k altitude range clutching wise....reducing weights is only part of the problem, the main thing is with the reduced power at altitude, you don't have the power to pull the stock helix/spring combination....you need to go to a shallower helix with a slightly stiffer driven clutch spring....stock helix is 48, i would suggest a 44 with a bikeman orange spring in the driven, and a bikeman white spring in the drive clutch with 68 gr weights which should give you about 82-8300 rpm at 10-11k altitude....if you ride at altitudes lower than 9k, just dropping weights to 68 might be all you need....getting the rpm above 8200 makes it a whole different animal, you mentioned the rpm fluctuating from 78-8000 rpm, which is my first clue that your helix is too steep for where you are riding...shallower helix/stiffer driven spring will help backshift and get your rpm to where the engine is singing, not loading up under too much helix or too tall of gearing....anyway, it's whats worked for me..
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Rpm
Yes utah northern part i ride several diffrent areas
Monte Cristo
Tony Grove
Uintahs
Manly monte as its so close to my house which where i ride monte is ranging between 7000-9100 ft elevation.
Yes utah northern part i ride several diffrent areas
Monte Cristo
Tony Grove
Uintahs
Manly monte as its so close to my house which where i ride monte is ranging between 7000-9100 ft elevation.
The dyno runs I've seen on here have shown the meat of the power to be 7900-8100 in stock form. 8200+ might make it seem like it's stronger and make more noise, but doesn't necessarily mean it is. Also not saying that there isn't a tach or two out there that read high.
one thing to keep in mind about the dyno results frequently posting peaks of 79-8100 rpm, these are all at the dynos altitude, most of which are less than 2000'.....you can expect to need 100-200 more rpm in the mountains at 8-10k....try the set-up i just posted above, Joe Namath guarantee you'll like it better...running side by side with stock alpha, easily outclimbs the stocker...
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