I will be having my carburetors cleaned soon and was wondering if I should have some performance mods done. I am planning on having a compression test done to see if the valves need to be shimmed. If shims can't bring the compression up to specs, I may have it bored out to 1200cc. If I have this done along with aftermarket exhaust and carburetor re-jetting, what can I realistically expect for horsepower/torque increases? I'm also wondering if it will dramatically alter the powerband, because I rarely go past 6000rpm and don't want it to be sluggish at lower rpm's.

 

If the compression is lower than the 159 psi standard manual numbers, you also want to check the piston clearance and rings. I realize that the manual only lists compression testing, but I prefer a leak down test normally.

I also prefer the stock cams and timing for normal street useage, ie 6k - 10k rpms running the stock exhaust. For more stock and hot rodding info, KZrider.com has alot of good info there.

Enjoy

 

That's what I was thinking about the stock parts, didn't want to end up with something all top-end. I was just thinking of that as an option if I had the motor rebuilt, didn't know how the stock exhaust would work with the bigger bore.