quote:Nice job.
Man, I need to pick up a small bike to race with you guys in the 200 class.
Yeah, in AHRMA its Grand Prix 200 Plus. From what I can tell the two strokers are the fast bikes in this class.
From the rulebook:
10.2.4 200 GRAND PRIX PLUS: This class combines a variety of engine designs and displacements, based on an index of performance. Eligible machines are listed below by make, model, displacement, and individual restrictions. Like-design models also are permitted. Displacement as noted below may not be increased beyond the allowable overbore. (See rule 9.7.2).
Aermacchi/H-D 250cc long-stroke (66mm bore x72mm stroke), wet clutch, original backbone chassis, maximum 30mm carburetor (i.e., up to 1965 only)
AJS/Matchless 250cc pushrod single, maximum 30mm carburetor
Ariel Arrow 250cc twin, original frame and forks, one 32mm or smaller carburetor
Benelli 250cc pushrod single, maximum 30mm carburetor
BMW R26 250cc single, maximum 30mm carburetor
Bridgestone 175cc twin, maximum 22mm carburetors
Bridgestone 200cc twin, maximum 20mm carburetors
BSA/Triumph 250cc single, maximum 30mm carburetor
Bultaco 125cc water-cooled GP TSS (round barrel only)
Bultaco 175cc air-cooled single (round barrel only), maximum 30mm carburetor
Bultaco 200cc air-cooled single, maximum 4-speed, maximum 28mm carburetor
Ducati 125, 160, 175, 200cc single
Hodaka 125cc
Honda CR110 (CR93)
Honda CB/CL 160, 175cc twin
Honda CA/CB 125, 160cc twin
Indian Arrow 250cc single, maximum 30mm carburetor
Moto Guzzi 250cc pushrod, maximum 30mm carburetor
MV 200cc “works” or replica single or twin
MV Augusta 250cc pushrod, maximum 30mm carburetor
Norton 250cc pushrod twin, maximum 30mm carburetor
Ossa 175cc, maximum 30mm carburetor
Parilla 250cc pushrod, maximum 30mm carburetor
Parilla 200cc production racer
Puch/Allstate 250cc split single, maximum one 32mm carburetor
Rumi 125cc flat twin
Triumph 200cc T20 Tiger Cub, maximum 250cc with allowable overbore; maximum 30mm carburetor
Villiers-based 250cc two-strokes such as Cotton, DKW, Greeves, maximum 32mm carburetor
Yamaha AS1 125cc twin (pre-1968), cast iron cylinders only
Yamaha CS3 and CS5, maximum 20mm carburetors or carburetor bore size
Yamaha CT1 175cc single (no Noguchi engine components), maximum 30mm carburetor
Yamaha YCS1 180cc twin (pre-1969), cast iron cylinders only, maximum 22mm carburetors.
10.2.5 REQUIREMENTS AND MODIFICATIONS FOR GRAND PRIX CLASSES
a) All GP class motorcycles must be fully GP kitted, with no lights, no starting mechanisms, no street equipment or associated brackets (factory-welded brackets may be retained if desired), low narrow handlebars (maximum width 32 inches). Fairings are encouraged.
b) Frame may be changed to racing type, though must be period type and style. (Refer to rule 9.7.3)
c) Front forks may be changed, though must be period type and style. “Ceriani” type may be no larger in diameter than 35mm, unless supplied as OEM on that motorcycle.
d) Period retrofit gearboxes are permitted (i.e., Quaife, Shaflieghtner). Maximum 6 speeds unless otherwise stated.
e) Front disc brakes are prohibited. Rear disc brakes are permitted, provided they are period equipment.
f) Magnesium engine cases are allowed in 500 Premier.
g) The number of valves in the cylinder head may not be increased or decreased from stock.
h) No more than one carburetor per cylinder.
i) All modifications must be consistent with the spirit of the class and period.
j) Appearance and workmanship of a reasonable standard shall be enforced.
k) Two-strokes must use silencers.
l) Maximum rim width WM3 in all GP classes.
Honda go sideways!
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