Must retain OEM clutches. Springs, weights, ramps, helix may be changed.
Gear ratios and chain may be changed.
No machining of clutch surfaces.
Track and Suspension
Speed tracks are NOT allowed in stock classes. Minimum 0.500 inch lug height.
OEM suspension must be used,addition or removal of wheels permitted.
Enviromentally friendly lube systems NOT allowed.
OEM ski's or aftermarket ski's must be a minimum of 40 inches.
Must retain OEM drive sprockets.
No lowering of the machine is allowed.Suspension must retain 2 inches of front and rear travel. The only way of lowering a sled is by using the provided factory adjustments. No straps, chains or wires permitted.
Carbide tiped trail studs only.
Frame and Body
All factory installed componants must be present and un modified. Hood, Ski's, Frame, Gas tank, Carbs, Air box, Suspension, Seat.
No drilling or lightening of sled permitted.
Engine
No componant of the engine may altered, changed, reduced or enlarged from the
engine manufacter original stock specifications. Nor may any additional componants be added to the engine.Blue printing of engines is not allowed. No removal of material whatsoever will be allowed. This is to include polishing, port matching, deburring, glass or sand blasting surfaces or materinal removal for the purpose of
engine balancing or other reasons.
No more than one cylinder base gasket to a cylinder.
No aftermarket reeds, reed spacers, pipes,cans, air boxes, carbs.
Oil injection must be functional if equiped from factory.
No turbo or Nitrous allowed.
Drive
Must retain OEM clutches. Springs,weights,ramps,helix may be changed.
Gear ratios and chain may be changed.
No machining of clutch surfaces permitted.
No light weight drive shafts or jack shafts.
Track and Suspension
Speed tracks are NOT allowed in Improved, minimum of 0.500 lug.
OEM front suspension must be used,addition or removal of wheels permitted.
Idler wheel size and material change permitted.
Enviromentally friendly lube systems NOT allowed.
OEM ski's or aftermarket ski's must be a minimum of 40 inches.
Rear suspension can be NON OEM. Must be a trail suspension.
Suspension must retain 2 inches of front and rear travel.
Frame and Body
Hood, Seat, Gas tank, Front suspension, must be OEM.
Engine
Trail Improved stock 500-900.
Must retain OEM cylinders, porting and polishing,balancing,blueprinting allowed.
must maintain stock carbs but may be modified.
Engine may be bored to a class cc limit. A 1% overbore limit allowed.
OEM carbs must be used but may be modified.
Air box modification or removal allowed.
Oil pump may be removed or disabled.
Cool down systems NOT allowed.
Heat exchangers can NOT be modified or removed.
Aftermarket reeds,reed spacers, pipes, cans allowed.
No turbo or Nitrous allowed.
1000cc and up in this class.
RX-1 with turbo must run in this class.
Trail Open allowed aftermarket carbs.
OEM stroke may be changed.
Any aftermarket cylinder allowed.
Turbo or Nitrous allowed.