Jr. Modified
Class Rules
1. Engines may be 1 or 2 cylinders with original carburetion, not exceeding 20 HP from the OEM.
2. Cylinder must not exceed 0.030 over original bore diameter.
3. Stroke must meet OEM spec for that engine
4. No valve or camshaft changes or modifications allowed
5. Only internal modification for increased strength allowed
6. Exhaust may be modified
7. Engines may be changed
8. Engine rpm may be modified
9. All tractors must be naturally aspirated
10. Tractor must have stock rear end of a lawn and garden type.11. Gear ratio changes allowed.
12. Clutch changes or modification allowed.
13. Rear-ends may be locked
14. Rear-end modifications allowed for increase strength ONLY!
15. Tractor must use stock frame, only modification for engine change allowed
16. Tractor must have 12" high back seat or 12" high bar behind driver
17. Maximum tire size: 26x12x12