| from Hottrax website...
MODERN CLASSIC SUPERBIKE & SUPERCUP CHAMPIONSHIP
NEW! 3 races each weekend including qualifying and warm up.
NEW! Modern Classic motorcycles from the age of Kawasaki ZX7RR’s, Yamaha YZF750, Ducati 916 etc. All will be 750 cc 4 cylinder, 975cc triples or twin cylinders up to 1000cc.
NEW! Minimum rider age is 30 years old
NEW! Bikes must be older than 10 years on 1st March 2012
Seems a good compromise; and allows DD mates to race with big bike mates | 
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