CLICK HERE for 2009 AMA Racing Stock Class Approved Machines.

CLICK HERE for 2009 AMA Racing Motocross Stock Rule Clarification Chart.

AMA STOCK CLASS RULE

Per the 2009 AMA Racing Rulebook Chapter 1, Section 1.2, Paragraph B (pages 11-12): Stock Class Additional Equipment Standards:

1. To be eligible for the STOCK CLASS, the following cannot be changed or modified:

a. Air box frame, carburetor (jetting changes allowed), rim size, electronics, stroke, exhaust system, swing arm, internal engine components, wheel hubs

b. Cylinder re-plating is allowed but must retain the original manufacturers bore.

c. Changes to carburetor jetting are allowed.

d. Clutch plates, pistons and piston rings may be accessory items as long as they maintain the stock shape, design and material of the OEM parts.

e. High compression pistons are not allowed.

f. All other internal engine components must be stock OEM parts.

g. Material may be added to the existing frame for strength, including welding. These changes shall not affect frame geometry.

h. OEM front and rear suspension can be altered with internal modifications only. Shock linkage and suspension spring rates may be changed to any commercially available part.

2. To be eligible for stock classes in oil injection systems used in stock classes, only oil may be put in the reservoir. Pre mix gasoline is not allowed in the oil injection system. Any items not listed above may be changed or modified.

Violations of the stock class rules as determined by the protest process or by the referee of the event will result in a disqualification from the event. A second violation of the stock class rules will result in a disqualification from the event and a suspension from AMA competition for one year. However, if a violation is deemed by the referee to be cosmetic in nature, with no performance advantage or willful misconduct involved, he may issue a warning or fine in lieu of disqualification.

In addition to the above AMA Stock Rule, the following apply to the Stock classes for the AMA Amateur National Motocross Championship:

  1. Parts/components that may be replaced or added include but are not limited to: fuel filters, air filters, gas line, handlebars, crossbar pads, non-metal open ended hand guards, serrated foot pegs, lower fork leg protectors, spokes and nipples, decals, spark plugs, spark plug caps, sprockets, handlebar mounts, seat covers, triple clamps.
  2. The kill switch on all 51cc automatic machines must be stock and fully functioning.
  3. Class 18: Oil injection systems must be present and fully functioning. Only oil may be put in the reservoir. Pre mix gasoline is not allowed in the oil injection system.
  4. Removal of gaskets, O-rings or other components is NOT allowed. Port cleanup is NOT allowed.
  5. Aftermarket front fork hole shot devices are NOT permitted.
  6. Metal hand guards are NOT permitted.
  7. Rims can be replaced with OEM or aftermarket rims of the same size and width.

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