250/450 SuperStock Class Rules for 2012

This is the rules for the Sunshinemicrosprints Sportsmans club races

1) Driver age: Driver shall be at least 12 years old or older. No maximum age limits.
2) Engines:
A) Engines will be completely stock, and unmodified except as specified in the rules. If it doesn’t say you can do it, you can’t. No porting, polishing, grinding, machining, or substituting parts etc. unless rule says you can do it.Any exemptions to the rules will be by club member vote.
B) Single cylinder, Stock 250 2-stroke, or Stock 450 4-stroke engines.
C) Engines may be any manufactured year. Only dirt bike or ATV engines may be used (no road race engines allowed).
D) Any Piston may be used, as long as stock bore is retained.
E) Any valve of any material may be used, as long as stock dimensions are retained. Valve springs are open. Standard valve job is allowed to re-freshen head.
F) Stock ignition system must be used and functional, timing may be altered, stock rev limit must be retained.
G)450 4-strokes Heads may be surfaced for flatness, but no other modifications allowed. 250 2-strokes may have porting in the cylinder and run a cool head.
H) 450 4-strokes must have an operating clutch (to encourage electric start), 250 2-strokes do not need an operating clutch, and it may be machined and welded.
I) Electric start is not mandatory, but is highly encouraged. 
J) Any replacement connecting rod and crankshaft may be used, crankshaft must be steel, no lightweight or knife edged cranks. No machining or modifications allowed. No strokers. No Titanium or lightweight materials unless used as factory balancing.
K) Oil system may be modified for engine durability. No Dry sump if it was not stock on that engine.

L) NO ceramic bearing in engine
M) Mufflers: 250 2-strokes may use any pipe and muffler combination . 450 4-strokes may use any muffler and pipe combination .
N) Minimum weight: 610 lbs for 250-2 stroke, and 450-4 stroke.
O) Wings: Max of 12sq ft
P) Fuel-GAS ONLY  allowed for 250 2-strokes and 450 4-strokes. No performance enhancing additives.
Q) Race tires:
1-Dirt races will be either a American Racer sd48 or a Hoosier d25 on the right rear and all other tires will be open
2-Asphalt races will be run with the DOT rated 205-50-10 on the front and the 205-65-10 on the left rear,open dirt tire on the right rear(go as hard as you can find)                                                    R)Only two in car adjustments allowed(drivers choice)