rules are on 2up's web site
Adult 88cc - You must run a 10" inch. rear wheel. All bikes must be air-cooled, 4-stroke engines with open cradle frames. 12" inch. front wheel (maximum) are allowed. Manual clutches are allowed. Engine specs are 88 cc and below. Maximum wheel base is 45 inches. Motor will be teched on overall series winner.
Adult 10 Super Stock - XR/CRF50 or TT-R50 Bikes Only .
The following items must remain "Bone Stock" : Engine cases, engine head and cylinder (No aluminum heads allowed) (No cylinder spacers allowed), carburetor (re-jetting is OK. Choke must remain on carb.), carburetor manifold, engine appearance (do not paint orcoat cases), frame, swingarm, forks, wheels hub's (10" only front and rear), brakes, fuel tank.
Bikes can be modified by changing or adding the following parts: Upper tripleclamps, handle bars, grips, brakes cables, throttle cables, kill-switch, throttle assembly, sprockets, graphics, tires, pistons, rings, exhaust system, clutch springs and plates (clutch must remain fully automatic) CDI box, air filter, fork springs, rear shock, chain, sprockets, footpegs/mounts, skid plates, rims andspokes, shifter and brake lever, seat cover and foam, plastic (ie: fenders, shrouds, number plates can be replaced in color only, must have white backgrounds).
Adult 10 open - You must run a 10" inch. rear wheel. All bikes must be air-cooled, 4-stroke engines with open cradle frames. 12" inch. front wheel (maximum) are allowed. Manual clutches are allowed. Unlimited engine modifications are allowed. Maximum wheel base is 45 inches
