now i put in this clutch set up in my98 sx 8ab weights,g-p-g primary 49/43 helix green secondary,reed notch,punched out silencer. was riding today and she engages earlier 3000 rpms. factory engagement is 4000,is this more efficient for engagement at 3000 or does the primary have to be shimed to raise it to the factory setting of 4000.i have a picked track and i want the most out this set up.i think it should engage at 4000 like from the factory what do you guys think?
If you want a hard launch it's going to launch harder at 4000 no question. More torque/HP and kinetic energy working for you at the higher RPM.
how many shims do you think to bring it up to 4000
700scott
New member
it'll take alot of shimming and you might end up with coil bind. you might want to think about another primary spring with a higher tension to start and same to fully compress i don't have the book infront of me to tell you what might work for ya though. i'll look tomorrow.
98srx6
New member
You may want to look into getting the proper spring rather than using the shim.
flying dutchman
Member
Each shim raises the engagement app 100 rpm. I heard a max of 3 shims. After that you need to find a different spring/weight combo 
98srx6
New member
The shim (1) that was in my sled when i got it raised engagement ~1000 rpm
what you have there is a aftermarket spring shim, they come in 2mm,4mm,6mm,10mm,12mm, these will allow you to raise the engagement up. The factory shims are the ones that only raise it approx. 100rpm per shim. If what you typed below is correct, you have a green-pink-green, the spring is 30/119 kg, to raise the engagment only up you will want a spring with higher first number and same finish(if your rpm is correct at wide open), Do you still have the short cover on prmary? if you do the closet spring to get you more in engagment and same shift rpm is the yamaha yellow-silver-yellow, it is 35/118 kg, you would probally need 3 stock yamah shims with this to be up a 1000rpm from where you are now. What you have to becarefull with is using too big of a shim, it will coilbind the spring, and it will just smoke the belt and probally break it, be sure to check for coilbind when using shims, and also, it will raise the shift rpm a very tad bit also by shimming the spring, its working in a shorter stroke now and will also diminish faster.
MountainMax
New member
for the best start you want to raise the engagement rpm's as high as you can without spinning too much, for racing, for trail driving, if youre happy with the power starting off at 3000 rpm stay with it.