2.6 Novice GTU/GTO and Amateur GTU/GTO classes
2.6.1 GTU
Class displacement limits are set as follows:
• Up to 430cc two or more cylinder, two stroke, unlimited origin
• Up to 550cc two or more cylinder, two stroke, if frame is from a motorcycle
manufactured for street use in North America
• Up to 550cc single cylinder, two stroke, unlimited origin
• Up to 850cc two cylinder, four stroke, four or more valves per cylinder
• Up to 750cc three cylinder, four stroke, four or more valves per cylinder
• Up to 640cc four or more cylinder, four stroke
• Up to 900cc three or more cylinder, four stroke, air cooled
• Unlimited displacement two cylinder, four stroke, two or three valves per cylinder
• Unlimited displacement single cylinder, four stroke, unlimited origin