SECTION 8 - CLASSES FOR AHRMA RACE MEETS
VINTAGE ROADRACE
1. 500 PREMIER: 1968 and earlier 500cc four-stroke OHV/OHC, or 750cc sidevalve machines. See Section 10.2.1.
2. GRAND PRIX: 1968 and earlier 350cc four-stroke machines; 350cc air-cooled, single-cylinder, two-strokes with no more than five speeds; 250cc two-stroke water-cooled singles; 250cc twin-cylinder air-cooled two-strokes with no more than six speeds. See Section 10.2.
3. 250 GRAND PRIX: 1968 and earlier 250cc four-stroke machines; 250cc air-cooled two-stroke singles with a maximum of five speeds; 175cc two- stroke water-cooled singles; 175cc air-cooled, twin-cylinder, two-stroke machines with no more than six speeds. See Section 10.2.3.
4. 200 GRAND PRIX PLUS: This class combines a variety of engine designs and displacements, based on an index of performance. See Section 10.2.4.
5. FORMULA 750: Fully GP-kitted four-stroke machines up to four cylinders, manufactured as 600-750cc and built prior to December 31, 1972. See Section 10.3.1.
6. FORMULA 500: Two-stroke and certain four-stroke machines up to 500cc grouped on an index-of-performance basis. See Section 10.3.2.
7. FORMULA 250: Two-stroke air-cooled machines, including singles up to 360cc and twins up to 250cc, and certain four-strokes. See Section 10.3.3.
8. FORMULA 125: Machines up to 125cc. See Section 10.3.4.
9. FORMULA VINTAGE: Open to machines eligible for 500 Premier, Formula 750, Formula 500 and Sportsman 750. See Section 10.3.5.
10. CLASS C: Intended for AMA “Class C” machines up to and including those manufactured December 31, 1951, as ‘51 models. Also CLASS C HANDSHIFT, a championship class run together with, but scored separately from, Class C. See Section 10.4.
11. PRE-1940 GRAND PRIX: 1940 and earlier Grand Prix or modified street machines, including 500cc single-cylinder OHV and OHC and 750cc sidevalve machines. See Section 10.4.2.
12. CLASSIC SIXTIES: 1960 era and earlier (or like model) Grand Prix/Clubman 500cc four-stroke OHV and OHC machines, or 750cc sidevalve, in basically standard form. Plus 350cc OHV and OHC as a non-championship class. CLASSIC SIXTIES 650: Pre-unit 650cc and certain other machines, run with but scored separately from Classic Sixties. See Section 10.4.3.
13. SPORTSMAN: 1972 and earlier four-stroke, maximum three-cylinder streetbike-based machines, divided into 350cc, 500cc and 750cc classes. See Section 10.5.
14. NOVICE HISTORIC PRODUCTION: 1972 and earlier production street machines with the standard OEM frame, swingarm, forks and handlebar mounts. Engines use the original OEM bore and stroke. Classes are Lightweight (four-strokes up to 500cc, 250cc two-strokes and certain 350cc two-strokes) and Heavyweight (four-strokes up to 750cc and 350-500cc two-strokes). This class is intended for novice riders. See Section 10.6.
15. BEARS®: Two-cylinder pushrod machines built up through 1968 and competing under Formula 750 specifications. See Section 10. 7.
14. SIDECAR: 750cc four-stroke, twin-cylinder, or 500cc two-stroke, air-cooled, twin-cylinder powerplants. Rules available from the AHRMA national office.
15. EXHIBITION: Non-competitive exhibition or “rolling display” rides. Guidelines available from the AHRMA national office.
BATTLE OF TWINS®
1. BOT FORMULA 3: Pushrod OHV machines to 1000cc, OHC 2- or 3-valve to 800cc, OHC liquid-cooled 4-valve to 650cc. Pushrod OHV machines over 900cc must run under Supersport specifications See Section 10.11.
2. BOT FORMULA 2: Pushrod OHV machines to 1250cc, liquid-cooled OHC to 750cc, air-cooled 2-valve OHC to 1000cc and air-cooled 4-valve to 1000cc. See Section 10.11.
3. BOT FORMULA 1: No displacement limits and no limitations to engine modifications, with the exception of water-cooled 4-valve twins over 900cc. See Section 10.11.
4. OPEN TWO-STROKE: Air-cooled two-stroke motorcycles to 500cc; water-cooled two-strokes with tubular frame to 400cc; and modern 250cc GP type machines. See Section 10.11.
5. TRIUMPH THRUXTON CUP CHALLENGE: A spec class sponsored by BES Incorprated for the Triumph Thruxton 900. For rules, visit www.ahrma.org or contact the AHRMA office.
SOUND OF SINGLES®
1. SUPER MONO™ 2: Four-stroke motorcycles with more than two valves up to 510cc and two-valve four-strokes to 610cc. See Section 10.12.
2. SUPER MONO™: Unlimited displacement four-strokes. See Section 10.12.
3. SOS TWO-STROKE: Two-stroke singles to 550cc. See Section 10.12.
4. MOTARD: Motocross, off-road, dual-sport and motard-specific four-stroke single-cylinder machines of unlimited displacement (replaces Production Singles). See Section 10.12.
SOUND OF THUNDER®
1. SOUND OF THUNDER®: Unlimited displacement four-stroke singles and twins; three-cylinder machines to 1000cc; and twin-rotor rotary engines. See Section 10.13.
VINTAGE MOTOCROSS
1. PREMIER LIGHTWEIGHT: Certain pre-modern-era machines up to 250cc. See Section 11.1.1.
2. PREMIER 500: Pre-1965-era machines up to 500cc. See Section 11.1.2.
3. PREMIER OPEN TWINS: Pre-1965-era twin-cylinder machines 600cc and larger. See Section 11.1.1.
4. 100cc MOTOCROSS: 88-100cc 2-stroke and 4-stroke production machines up to 1974. See Section 11.1.1.
5. CLASSIC 125: 125cc two-strokes and four-strokes up to 150cc, manufactured through December 1971 and any like machines. See Section 11.1.5.
6. CLASSIC 250: Specific 250cc and smaller two-stroke machines introduced just after the Premier Lightweight era, as well as the heavy 350cc non-unit motorcycles. See Section 11.1.6..
7. CLASSIC 500: Specific motorcycles introduced just after the Premier 500 era. See Section 11.1.7.
8. SPORTSMAN: 125cc, 250cc and 500cc classes for machines up to model year 1974. See Section 11.1.8-10.
9. SPORTSMAN OPEN TWINS: Twin-cylinder machines up to model year 1974. See Section 11.1.11.
10. Open Age: Any AHRMA-eligible rider on any AHRMA-eligible vintage machine. See Section 11.1.12.
11. +40: Riders over 40 years of age on any AHRMA-eligible vintage machine. See Section 11.1.13.
12. +50: Riders over 50 years of age on any AHRMA-eligible vintage machine. See Section 11.1.14.
13. +60: Riders over 60 years of age on any AHRMA-eligible vintage machine. See Section 11.1.15.
14. +70: Riders over 70 years of age on any AHRMA-eligible vintage machine. See Section 11.1.16.
15. WOMEN: Riding any AHRMA-eligible vintage machine. See Section 11.1.17.
POST-VINTAGE MOTOCROSS
1. Historic 125: Certain 125cc and smaller motorcycles built up to and including the 1977 model year as the first-generation of long-travel machines. See Section 12.1.2.
2. Historic 250: Certain 126-250cc motorcycles built up to and including the 1977 model year as the first-generation of long-travel machines. See Section 12.1.3.
3. Historic 500: Certain 325-460cc two-strokes and four-strokes up to 636cc built up to and including the 1977 model year as the first-generation of long-travel machines. See Section 12.1.4.
4. Historic Four-Stroke: Certain four-stroke machines built up to and including the
1978 model year with up to 636cc. Overhead cam machines are limited to 500cc. See Section 12.1.5.
5. Gran Prix 125: Certain post-1977 motorcycles up to 125cc. See Section 12.2.2.
6. Gran Prix 250: Certain post-1977 motorcycles 126-250cc. See Section 12.2.3.
7. Gran Prix 500: Certain post-1977 motorcycles 325-500cc two-stroke and up to 580cc four-stroke. See Section 12.2.4.
8. Gran Prix FOUR-STROKE: Certain 185cc-580cc four-stroke motorcycles that came just after the Historic Four-Stroke period. See Section 12.2.5.
9. Ultima 125: Certain motorcycles up to 125cc that do not have disc brakes or power-valve type mechanism built directly into the engine. See Section 12.3.2.
10. Ultima 250: Certain 126-250cc motorcycles that do not have disc brakes or power-valve type mechanism built directly into the engine. See Section 12.3.3.
11. Ultima 500: Certain 325-580cc motorcycles that do not have disc brakes or power-valve type mechanism built directly into the engine. See Section 12.3.4
12. Ultima FOUR STROKE: Certain 200cc-580cc four-stroke motorcycles that were produced either with a single-shock rear suspension or a newer engine technology. See Section 12.3.5.
13. Open Age: Any AHRMA-eligible rider on any eligible machine. See Section 12.4.1.
14. +40: Riders over age 40 on any eligible machine. See Section 12.4.2.
15. +50: Riders over age 50 on any eligible machine. See Section 12.4.3.
16. +60: Riders over 60 years of age on any eligible machine. See Section 12.4.4.
17. Women: Female riders on any eligible machine. See Section 12.4.5.
OBSERVED TRIALS
1. PREMIER HEAVYWEIGHT: Pre-1965 era machines 350cc and larger. See Section 13.1.1.
2. PREMIER LIGHTWEIGHT: Pre-1965 era machines up to 250cc. See Section 13.1.2.
3. RIGID: Any non-swingarm machine. See Section 13.1.3.
4. GIRDER FORK: Any rigid-frame, girder-fork machine. See Section 13.1.4.
5. MODERN CLASSIC: Any unit-construction machine up to model year 1979. See Section 13.1.5.
6. CLASSIC: British kit-framed two-strokes up to model year 1974 with 175cc or smaller OEM engine, and Spanish 4- speeds to 250cc in original OEM frame. See Section 13.1.6.
7. BEGINNER: A non-championship class for beginning trials riders on any motorcycle eligible for AHRMA trials. See Section 13.1.7.
DIRT TRACK
1. DINOSAUR: 1951 and earlier 500cc OHV and 750cc sidevalve. See Section 14.2.1.
2. CLASSIC: 1967 and earlier machines; the two classes include 0-250cc, and 500cc OHV/ 750cc sidevalve. See Section 14.2.1-3.
3. SPORTSMAN: 1974 and earlier dirt trackers, divided into classes for 0-250cc, 251-600cc and 601-750cc machines. See Section 14.2.4-6.
4. SEVENTIES SINGLES: Post-vintage-era 500cc and smaller four-stroke machines such as competed in the late 1970s. See Section 14.2.7.
5. SEVENTIES TWO-STROKE: 1981 and earlier air-cooled two-strokes up to 250cc. See Section 14.2.8.
6. SENIOR: Riders over 50 years of age on any Sportsman-eligible machine. See Section 14.2.9.
7. SUPER SENIOR: Riders over 60 years of age on any Sportsman-eligible machine. See Section 14.2.10.
8. NOVICE: A non-championship class run at selected events for entry-level riders on Sportsman-eligible machines. See Section 14.2.11.
TT
1. DINOSAUR: 1951 and earlier machines, no limits on engine displacement. See Section 14.3.1.
2. CLASSIC: 1967 and earlier machines; the two classes include 0-250cc, and Open. See Section 14.3.2-3.
3. SPORTSMAN: 1974 and earlier dirt-trackers, divided into classes for 0-250cc, 300-600cc and 601-750cc. See Section 14.3.4-6.
4. SEVENTIES SINGLES: Post-vintage-era 500cc and smaller four-stroke machines such as competed in the late 1970s. See Section 14.3.7.
5. SEVENTIES TWO-STROKE: 1981 and earlier air-cooled two-strokes up to 250cc. See Section 14.3.8.
6. SENIOR: Riders over 50 years of age on any Sportsman-eligible machine. See Section 14.3.9.
7. SUPER SENIOR: Riders over 60 years of age on any Sportsman-eligible machine. See Section 14.3.10.
8. NOVICE: A non-championship class run at selected events for entry-level riders on Sportsman-eligible machine. See Section 14.3.11.
CROSS COUNTRY
1. SPORTSMAN, 88-200cc & 201cc-Open: Novice, Intermediate & Expert. See Section 15.1.1.
2. CLASSIC: Novice, Intermediate & Expert. See Section 15.1.1.
3. PREMIER: Novice, Intermediate & Expert. See Section 15.1.1.
4. +50: Novice, Intermediate & Expert. See Section 15.1.1.
5. +60: Novice, Intermediate & Expert. See Section 15.1.1.
6. +70: Novice, Intermediate & Expert. See Section 15.1.1.
7. HISTORIC: 88-200cc & 201cc-Open: Historic-class machines; Novice, Intermediate & Expert. See Section 15.1.1.
8. POST-VINTAGE: 88-200cc & 201cc-Open: Grand Prix and Ultima-class machines; Novice, Intermediate & Expert. See Section 15.1.1.
9. POST-VINTAGE +50: Novice, Intermediate & Expert. See Section 15.1.1.
10. POST-VINTAGE +60: Novice, Intermediate & Expert. See Section 15.1.1.
11. POST-VINTAGE +70: Novice, Intermediate & Expert. See Section 15.1.1.
Also see Vintage and Post-Vintage MX class descriptions.