With the HPD clutch kit you will be REAL close to where you need to be.But like Scramblered said you need to check for full shiftout.you may need lighter or heavier weights to get where it needs to be.The kits are for general applications and there is many differant condition to take in to account.I think the kit you are getting has a brown spring,violet sec,S58 weights.TRy it with the stock S55 wieghts first.

 

I have the stock sprockets and stock helix in my clutch (for now) with s53 weights and mine does 73 MPH GPS topped out on asphalt, 75 deg temps, 1200 elevation. 4 PSI
With my mods as listed below.

Tire dia and inflation will matter too slightly as all the other factors mentioned.

Jim

 

Hmmm, marking the clutches, an interesting idea. Does it matter what you use? Crayon, tire chalk, white-out ? Ideally the primary will be wipped all the way to the top and the secondary all the way to the bottom?

 

Soap stone or chalck work the best they wipe off easily by the belt

 

The auto clutch sys won't allow you to get anymore speed out of it. Once that belt get's to the top of that pulley, thats all it's got unless you can get a bigger pulley. Changing the sprocket might not be a good idea either. If you do that, then it will lug the motor down and have a harder time to get up to speed. That's one of the down falls about the auto belt trans. It's kinda like 10 speed bike. Once your in 10th gear, it's hard to pump it to get more speed out of it unless your going down hill.

 

gunman457 have said it all,the black pencil mark must done straight
vertical all the way through the primary clutch,you didn't have to drawn
it down at the bottom tough it doesn't help anymore then.
after a WOT (wide open throttle) ride for some time,remove the cover and the mark
should be erased at where the belt is climbing at...

 

hey Jimmy, if you ever wanna sell that scrammy, let me know first!


Fred.

 

Thats assuming you dont have the power in your motor. The 'chart' on the cover of Olav Aaen's clutch tuning handbook shows the relationship between RPM and speed. When the clutch is fully shifted out, the power of the engine starts gaining RPM and speed.

 

You may get a little more mph out of it, but it won't be much. you'll have to make a lot more power to get a higher rpm to maybe get a nother 1 mph out of it. Once you top out the pulley, your done. Unless you want to make your motor sing. I don't know how great the bottom end of Polaris motor is. That's the chance you'll have to take.

 

According to HPDs dyno charts stock peaks at about 6000RPM, the trail port peaks at about 7000RPM, the race mod at about 7250, and the power max at about 7800RPM. The Power Maxx doesnt have any bottom end parts in the kit, and even says its designed for the 400 bottom end, so the bottom end shouldnt be a problem. If you have the power to get to full shiftout you should be able to increase RPM from there (probably more than 1 MPH too).