F1
This class is a NOVICE ONLY class run under the same rule specification as F2. It is designed for beginning racers who may not feel comfortable racing with Experts and/or large grids and DOES NOT count towards Overall Championship points.

1. Maximum displacement of:
a. 112cc air cooled 4-stroke auto clutch- OSB defines auto clutch as any automatic or semi-automatic centrifugal clutch that is engaged by pressure on the foot operated gear shift lever. The addition of any bar mounted levers to aid and/or actuate any part of the clutch mechanism in any manner for an F1 bike above 100cc will render that bike illegal for the F1 class;
b. 100cc air cooled 4-stroke manual clutch;
c. 55cc water cooled 2-stroke; and
d. 65cc air cooled 2-stroke.

2. NO ROLLER ROCKER HEADS

3. Any engine mods within CC range.

4. Any frame and engine combination

 
F2
1. Maximum displacement of:
a. 112cc air cooled 4-stroke auto clutch- OSB defines auto clutch as any automatic or semi-automatic centrifugal clutch that is engaged by pressure on the foot operated gear shift lever. The addition of any bar mounted levers to aid and/or actuate any part of the clutch mechanism in any manner for an F2 bike above 100cc will render that bike illegal for the F2 class.
b. 100cc air cooled 4-stroke manual clutch;
c. 55cc water cooled 2-stroke; and
d. 65cc air cooled 2-stroke.

2. NO ROLLER ROCKER HEADS

3. Any engine mods within CC range.

4. Any frame and engine combination.

 
FW
1. Maximum displacement of:
a. 145cc air cooled 4-stroke- NO ROLLER ROCKER HEADS;
b. 63cc water cooled 2-stroke; and
c. special inclusion MZ125.

2. Any engine mods within CC range.

3. Any frame and engine combination.

 
F3
1. Maximum displacement of:
a. 134cc air cooled 4-stroke;
b. 65cc water cooled 2-stroke;
c. 80cc air cooled 2-stroke; and
d. special inclusion MZ125.

2. Any engine mods within CC range.

3. No limit on wheel size.

4. No GP frames allowed, all other frame and engine combo is allowed.

Legal bikes for this class include but are not limited to: Extreme 125, XR 100/big bore, KX 65, KTM 65, YZ/KX/RM/CR 80 air cooled, KLX/DRZ 110/big bore, NSR 50/big bore, Derbi 50/big bore, and Aprilia 50/big bore.

 
F4
1. Maximum displacement of:
a. 120cc water cooled 2-stroke, unlimited mods within CC range;
b. 235cc air cooled 4-stroke, unlimited mods within CC range; and
c. 160cc water cooled 4-stroke, unlimited mods within CC range.

2. No limit on wheel size.

3. Any frame and engine combination.

 
F5
1. Maximum displacement of:
a.250cc water cooled 2-stroke;
b.250cc water-cooled 4-stroke;
c.450cc air cooled 4-stroke;
d.DRZ/KLX 400 special inclusion with unlimited mods;
e.Unlimited displacement for Sportsman machinery that retains 19" or larger front rim.

2. Motard class only.

3. All models from the manufacturers designated as either 250cc 2-S or 250cc 4-S must retain stock bore and stroke.

4. Any engine mods within CC range.

 
F6
1. Maximum displacement unlimited.

2. Motard class only.

3. Any engine mods.

Legal bikes for this class include but are not limited to: CRF/YZF/KX/RMX/KTM 450, KTM 525, DRZ/XR 650, and CR/YZ/KX/RM 250.

All rules, class distinctions, and age limitations are subject to Race Director discretion. Classes may be changed to maintain a competitive balance or to accommodate unique machinery. If enough bikes show up that are “in-between” classes, we will do everything in our power to set up a class structure that will allow them to be competitive. Basically, whatever you show up with, we will find a place for you to race.


PROTEST RULES
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