Motorcycles must not exceed the following guidelines:
New rules for 2013 are in Red
Unlimited modification to suspension.
Unlimited modification to chassis.
- Unlimited wheel size.
- Unlimited modification to braking system.
- Unlimited modifications to Exhaust with sufficient silencer.
- Unlimited modifications to engine
- Unlimited modifications to carburetor.
Engine displacement must not exceed 100cc air-cooled 4-Strokes(2-valve), 50cc liquid-cooled 2-strokes, 62cc air-cooled 2-strokes, 110cc Horizontal air-cooled 4-stroke(2-valve), and NO liquid-cooled 4-strokes. +2cc maintenance overbores allowed
Yamaha TTR-125 allowed. May change fluids, gearing, wheels, carburetor jets/needle, suspension springs. Must use Stock un-modified engine, exhaust, carburetor, electronics.