[sho305]

The secondary can affect top speed by the spring and how far the belt drops down into it. The outside diameter would be your low gear so to speak, larger is lower initial gearing. Having been tuning on my 94c lately some stiff springs wont let the clutch close all the way and get belt to the top, ones that do the top speed is much better. Another issue is distance between clutches can affect the initial low gearing and/or the top gear ratio, same goes for belt length and width it will change how it rides in the sheaves. I have modded on my clutches to get them to open more and things like that to get max range of ratios. If your belt is just half inch from top of primary or bottom of secondary, it will make a difference in top speed. The only good part is when you get it working right you don't have to mess with it anymore. (when will that ever happen? lol) This is on my clone, it should roughly do around 40mph at just over 5K rpm on 22s. I only go that fast when I test it down a road, its a little hairy feeling even after getting the steering aligned right. Its just I'm out there with no belt/cage/helmet/etc since I rarely hit 30 in normal trail and yard riding.

This is not a good pic, but its the yamaha G9 shaft. It has a spline on the inside to hold the helix (actually the shoe carrier/hub as the helix ramps are on the inner sheave that is the movable) and has a taper fit on the end for the fixed outer sheave. The taper has a half moon key in the taper, pretty small thing. Then the threads at the end for the nut.