Make sure you follow proper primary sheave installation procedures. I've read way too many horror stories of people screwing this up and then complain that their bike perform poorly (usually dropped weights) and even many situations where their Cvts were damaged from improper installations.
Nothing hard about this but a few careful steps must be taken.
Few quick points.
- Make sure you maintain tension on the cam plate when sliding the primary sheave on the shaft and collar . Otherwise the weights can fall out of their channels and you'll need to disassemble your primary sheave to reinstall them. ( Very commun mistake!)
- If your belt is still in place during this installation make sure it's loose enough as to not get "pinched" by the sheave during installation . Your supposed to install two screws in your secondary sheave to open it up and witch loosens the belt tension when disassembling the cvt.
- When the sheave is first installed verify you have full cam plate engagement on the splines.
- Make sure the thick washer is centered and over the splines before threading on the nut.
-Do not use an impact to tighten the nut! Use a torque wrench and torque it properly. Not sure about the 450s but the 700s is 100ft/lbs
I use a choked rachet strap to stop the sheave from turning, but others have made wooden holders, or special wrenches. Many ways of doing it.
-Once this is done you can gradually start removing the pusher screws from the secondary sheave while spinning the sheave. Back them off a bit at a time and spin the sheave many, many times . The belt should gradually climb all the way up the secondary and drop right down into the primary as the spring tension is reestablished on the belt.
A good idea is to count your CVT ratio before and after you serviced your CVT. ( how many turns the primary needs to do before the secondary sheave makes one turn). With proper installation of shims you will gain more initial ratio compared to stock. In my case, stock was 2.45:1 and with 1.5mm of shim it was 2.75:1. My machined sheave has a ratio of 3:1
Plenty of YouTube videos on the subject so take the time to watch a few just to get familiar with things. All Yamaha Grizzly and Kodiak Cvts have the same basic procedures so don't worry if the video you view is of a Grizzly / Kodiak 700 and not a 450.