Max rpm issues for vmax 600 twin

[JacobM03]

I have a 1998 vmax 600 xtc twin which i changed the gear ratio from 23/39 to 21/39, put a 1.25” track on and cleaned everything and the carbs, seems to run very good other than im only hitting 7500 rpm no matter what, i read that power is till 8200 but my sled seems to only hit 7500 and dont want to go more, is this a specific issue?

 

[74Nitro]

These are known for being hard on rollers and weights. Have you checked the condition of those?
8200 would be the high end, 8000 is peak power.

 

[Maim]

x2 on clean and inspect the clutches. a new primary spring might not hurt as well.

 

[JacobM03]

I blew a belt today (it looked like in rough shape to begin with) and put on my spare and it seemed to pull harder and would go past 8000 rpm so that couldve been it I guess. But putting on that belt it looked like the secondary spring wouldnt go back out all the way. Might be because it was pinching the belt on install a bit? Backed out all the way after getting it moving. Also found out my secondary had in and out play? Like i dont have enough washers on that bolt maybe, theres thicker washers and thinner ones, the thick ones dont fit over the aluminum bushing and the bushing looks abit mushroomed out at the end is that ok?