stop that squeak

[pyrocam]

Yep. A less restrictive zorst will make it run leaner, which wil probably make it idle slower. A REALLY restrictive zorst will make it idle very slowly. A longer exhaust may make it speed up, unless it's reaaaaalllly reeeeeeaaaaaaalllllyyy long.

really? your exhaust really makes that much difference to the way the bike runs? Ive got a normal sized exhaust with a little knob on the end about 2cm diameter I guess If I removed that, how would it run?

[vifferman]

really? your exhaust really makes that much difference to the way the bike runs?

It's not just there for looks or to make the bike quieter.

Ive got a normal sized exhaust with a little knob on the end about 2cm diameter I guess If I removed that, how would it run?

Are we still talking about zorsts? this sounds a little dodgy...
Is an RGV150 2-smoke? Then stuffing around with the zorst will probably make it run like crap. If it's 4-stroke, then taking it off will make it sound more grunty, and run like crap, except maybe flat out, when it might produce a poofteenth more ponies.