Below is a preliminary breakdown of the class structure. The structure is designed to provide a variety of bike types and sizes a competitive class to compete. There are both stock and superbike classes. Bikes maybe entered in the primary class designed for the displacement, type, and wheel size. Additionally, the bike can be entered in the next class up (bump up a class). This is allowed so that a single bike can be run in multiple classes per weekend. Examples are listed at the bottom of the post.
Please review and feel free to ask questions. Look forward to seeing what everyone will be riding...
· Kids Novice
Up to 125cc air cooled, vertical cylinder four stroke
Up to 110cc air cooled, horizontal cylinder four stroke
Up to 50cc air cooled and water cooled two stroke
Engines must remain stock using all OEM parts. This includes airbox, ignition, carburetor, and exhaust.
Allowable changes are wheel sizes, tires, jetting, gearing, and controls.
Suspension components must remain OEM. Springs, fluid, and internal modifications are allowed.
OEM Brake components must be used. Brake pads can be changed.
If the modification is not explicitly stated as allowable then it is illegal.
Example of Eligible Bikes:
Yamaha: PW50, TTR50, TTR125
Honda: CRF50, CRF70, CRF/XR 100, CRF110, CRF125
Kawasaki: KLX110, KLX125
Suzuki: DRZ50, DRZ110
KTM, Husqvarna, and Cobra: 50cc 2 stroke models
Ohvale: GP-O 110, Manual and Automatic models
Bucci: BR10 110, Manual and Automatic models
- Kids novice riders will be moved to expert classes at the discretion of the SEMRA Officials.
· Kids Expert
Up to 73cc air cooled or water cooled, two stroke,
Up to 125cc air cooled, horizontal cylinder four stroke.
Up to 150cc air cooled, vertical cylinder four stroke
Ohvale GP-O 160 and Bucci BR10 160 are allowed in stock configuration
Example of Eligible Bikes
Yamaha: YZ65, TTR125
Honda: XR100, CRF100, CRF110, CRF125
Kawasaki: KX65, KLX110, KLX125, KLX140
Suzuki: RM65, DRZ125
KTM, Huqvarna, and Cobra: 50cc & 65cc 2 stroke models
Ohvale: GP-O 110 & 160, Manual and Automatic models
Bucci: BR10/12 110 & 160, Manual and Automatic models
With approval from SEMRA officials, Kids expert riders with appropriate machines can ride in adult classes that the bikes are legal for with SEMRA approval. Kids Expert riders cannot run in novice classes.
· Adult Novice
Ages 14 and up. Any SEMRA legal mini may compete in this class. When a competitor's times AND SKILL level approach the times being turned in the main classes, they will be moved. The rule of thumb will be 110% of main event lap times.
Adult Novice riders are not eligible to enter other classes.
· Stock 100/125 Lightweight
Stock 100/125, vertical cylinder air cooled 4 strokes
Eligible bikes allowed using either stock wheels or 16” wheels running DOT tires.
Honda XR100, CRF100, CRF125
Yamaha TTR125
Kawasaki KLX125
Suzuki DRZ125
Honda Grom is allowed using the stock 12” wheels running DOT tires.
Kawasaki Z125 Pro is allowed using the stock 12” wheels running DOT tires.
Engines must remain stock using all OEM parts. This includes airbox, ignition, carburetor, and exhaust.
Allowable changes are tires, jetting, gearing, and controls.
Suspension components must remain OEM. Springs, fluid, and internal modifications are allowed.
OEM Brake components must be used. Brake pads can be changed.
If the modification is not explicitly stated as allowable then it is illegal.
Riders of any weight
· Stock 100/125 Heavyweight
Stock 100/125, vertical cylinder air cooled 4 strokes 4 strokes
Eligible bikes allowed using either stock wheels or 16” wheels running DOT tires.
Honda XR100, CRF100, CRF125
Yamaha TTR125
Kawasaki KLX125
Suzuki DRZ125
Honda Grom is allowed using the stock 12” wheels running DOT tires.
Kawasaki Z125 Pro is allowed using the stock 12” wheels running DOT tires.
Engines must remain stock using all OEM parts. This includes airbox, ignition, carburetor, and exhaust.
Allowable changes are tires, jetting, gearing, and controls.
Suspension components must remain OEM. Springs, fluid, and internal modifications are allowed.
OEM Brake components must be used. Brake pads can be changed.
If the modification is not explicitly stated as allowable then it is illegal.
Rider and gear weighing a minimum of 185lbs
· Formula 2
Up to 65cc two strokes
Up to 125cc air cooled, horizontal cylinder four strokes
Up to 150cc air cooled, vertical cylinder four strokes
Superbike rules: Bikes may have unlimited engine mods but must not exceed max displacement.
· Formula 3
Up to 73cc two strokes
Up to 160cc air cooled, horizontal cylinder four strokes
Up to 180cc air cooled, vertical cylinder four strokes
Superbike rules: Bikes may have unlimited engine mods but must not exceed max displacement.
· Formula 4
Dirt bike based framed only, no GP style bikes allowed.
Wheel size 12” to 17”
Up to 105cc two stroke
Up to 150cc water cooled four stroke
Up to 190cc air cooled four stroke
Superbike rules: Bikes may have unlimited engine mods, but must not exceed max displacement
· Unlimited GP
GP style bikes only with 10” or 12” wheels
Up to 105cc two stroke
Up to 150cc water cooled four stroke
Up to 190cc air cooled four stroke
Superbike rules: Bikes may have unlimited engine mods, but must not exceed max displacement
· SuperMini
Any style chassis, 10” to 17” wheels
Up to 112cc two stroke
Up to 170cc water cooled four stroke
Up to 190cc air cooled four stroke
Superbike rules: Bikes may have unlimited engine mods, but must not exceed max displacement
· Supermoto
Full size dirt bikes only, no mini eligible bikes allowed.
250cc to 525cc, 2 stroke or 4 stroke engines
Dirt bike chassis with any wheels size greater than 16”
Superbike rules: Bikes may have unlimited engine mods, but must not exceed max displacement
Example of "Bump Up" classes:
Example 1: KX65 – Primary class is Formula 2 (max 2 stroke displacement of 65cc). The bump up class would be Formula 3.
Example 2: Stock TTR125 or CRF100 – Primary class would be Stock 100/125 (both LW and HW). The bump up class would be Formula 2.
Example 3: YZ85 or CRF150R – Primary class would be Formula 4. The bump up class would be Supermini.
Example 4: Ohvale GP-O 190 – Primary class would be Unlimited GP. The bump up class would be Supermini.
I have a 1969 Honda CL 90 (Logan 125 engine) that I built for vintage Mx. if I am reading it right and swap to street tires 17/17, I could race it in Adult Novice (over 13 years since being on a track) or in F2. Thoughts about this?
Hi preacher! Long time no see. I like the CL. I have been racing some vintage stuff too.
Hey Paul. Welcome to the forum. Cool looking bike! You are right on the rules. It could run in F2 or Adult Novice. Throw some tires on and come join us. Let me know if you have any other questions. Look forward to seeing you at the track soon. Steven
Will do! I look forward to racing with SEMRA again! Thank you.
Hi Paul,
Look forward you seeing you at the races. Adult Novice was my class back in 2007. Got my first motorcycle race win in adult novice after 40 years of trying! Never to late.
No F1 anymore? Still have my XR-50/108. I think the rest of the WV crew still has theirs as well.
Hey Carl. Appreciate the question. We are trying to maximize track time for the most popular bikes with the current class structure. When putting together this structure, I looked at the entries for past SEMRA races and F1 was not as well attended as other classes. If there is enough interest then we will certainly consider making adjustments.
Hey Carl. We have room in the race schedule for one more class. The rules have been slightly adjusted for F2. The 2T displacement was reduced t0 65cc. We also added a new F3 class (old F3 when to F4) that will serve as a step between the 125cc 4T/65 2T and the 150Rs/105cc 2T. This setup also eliminates the need for having an exception in F2 for the Ohvale/Bucci 160s.
Thanks. In Ohio they allow stock 100 to bump up to F1 (f3 I think they call it) where they are more competitive. Just a thought.
@Carl Hill The current setup allows for the stock 100 bikes to bump up to F2. We will continue to evaluate the interest in each class to optimize the structure. We also plan on having a practice / SEMRA reunion later this year. We will use opportunities like that to speak with riders to gain additional feedback and hopefully we will get more feedback like what you have provided.
Thank you! Steven