Here are the specs:
Note the 50 pound penalty for OHC engines. Otherwise, it looks like lots of fun if not cheap.
They only have to LOOK stockish:
4.3.5.2. CLASS REQUIREMENTS
4.3.5.2.1. Approval of Hot Rod Cruiser Motorcycles
Hot Rod Cruiser motorcycles are 4-stroke, V-Twin production
cruiser machines produced and manufactured for street use.
Approval must be submitted through AMA/Prostar. All bikes
must be 1998 or newer factory production models. Only the following
brands and models are allowed in competition: Harley-
Davidson (V-Rod, Sportster, or FX), Honda (VTX, Shadow),
Indian (Scout), Kawasaki (Mean Streak or Vulcan), Suzuki
(Intruder), Victory (V92) or Yamaha (Road Star, Warrior). Must
have been originally produced as 1100cc to 1800cc model VTwin
cylinder class bike. *Minimum weight: SOHC or DOHC 800
lbs, push rods 750 lbs.
4.3.5.2.2. BODY
Must have originally been produced as a V-Twin cruiser. Stock
fuel tank and side covers mandatory. Modifications to stock fuel
tank and side covers are permissible. Fenders may be replaced
with cosmetic duplicates of the original parts. Duplicates must
visually resemble the original parts in design and style for model
year as determined by VIN number. Updating of bodywork permissible
only on same models. Lower air dams permissible.
Fairings and windscreens prohibited unless OEM. Brand name
must appear on both sides of motorcycle. Operational cruiserstyle
DOT hi-beam, low-beam headlights and DOT taillights with
brake lights required. The use of turn indicators and mirrors is
optional.
4.3.5.2.3. BRAKES
Hydraulic type, front and rear, mandatory. Minimum size: 7-inch
diameter x .187-inch thickness for approved aftermarket rotors
or .187-inch thickness OEM rotors.
4.3.5.2.4. CARBURETOR / FUEL INJECTION / INTAKE
OEM Fuel injection systems permitted if originally equipped.
Aftermarket fuel injection management systems permitted that
plug "in-line" with bike's ECU, must plug into stock wiring harness.
Aftermarket units must be generally available commercial
parts that retail for under $1,000. Electronic or mechanical
enrichening devices must remain installed, but may be deactivated.
Fuel lines and vent lines may be replaced. Aftermarket
fuel filters may be added. Multi-aftermarket carburetors/throttle
bodies permitted with a maximum of (1) one carburetor/throttle
body throat per cylinder, multi-dual throat carburetors/throttle
bodies not allowed. Fuel injection may be replaced with carburetors.
Snap back throttle return is mandatory.
4.3.5.2.5. CLUTCH
Slider clutches prohibited. No clutch management parts i.e.; airclutch, proportioning valves or hydraulics, allowed. Cable operated
clutch can be converted to manually activated hydraulic
clutch. Mechanical lock-ups permitted.
4.3.5.2.6. CONTROLS
Handlebar controls must be located in the stock position. Brake
pedal, shift lever may be rear set, but foot pegs must be at least
15-inches in front of rear axle vertical centerline.
4.3.5.2.7. ELECTRICAL
Computers and/or data recorders prohibited. Exhaust gas temperature
meters permitted. IGNITION: Aftermarket ignition box
permitted. Replacements must be available for immediate shipment
from U.S. warehouses to any of the manufacturer's U.S.
retail outlets for sale to the public. Availability must be maintained
throughout the current racing season. The use of external
belt drive magneto ignitions and 2-steps are prohibited.
4.3.5.2.8. ENGINE
Must be an 1100 to 1800cc 4-stroke V-twin cylinder production
engine specifically designed and manufactured for a production
motorcycle with a maximum displacement of 1800cc. Class limit
displacement may be achieved by cylinder overbore only - stock
stroke length must be maintained. No Nitrous, turbo or superchargers
permitted. Engine manufacturer will determine make
of bike. Engine type or configuration, crankshaft configuration
and stroke, cam drive location in the engine, number of valves,
material and castings of cylinders, cylinder heads, and
crankcases and any major element used in the crankshafts and
camshafts may not be altered from the original model except as
noted. OEM crankshafts may be lightened. Aftermarket, stock
size rods are permissible; titanium rods prohibited. CYLINDER
HEADS: Stock OEM cylinder heads mandatory. Porting permissible.
Valve locations and angles may not be altered. Oversize
valves permitted. Aftermarket rocker arms and push rods (for
push rod engines) permitted. CYLINDER: OEM cylinder casting
mandatory. Cylinder sleeving, replating or recoating permitted.
CAMSHAFTS: Reground OEM or aftermarket cam shafts permitted.
Cam shaft drive may converted to chain drive or gear
drive. TRANSMISSION: Stock OEM., Transmission must be
shifted from gear to gear manually or by air or electric shifter.
RPM or computer-shifted gearboxes are prohibited. Bikes must
be ridden from end of track to tech under power (not pushed or
towed). Final drive may be converted to shaft, belt or chain.
Push starting or roller starts are not permitted. External starters
are prohibited.
4.3.5.2.9. FRAME
Stock OEM frames required. Frame must display vehicle identification
number (VIN) in original location. Strengthening modifications
to stock frames are permitted as long as the frame is not
weakened. Strengthening gussets and/or tubes may be added
but none removed. Accessory brackets (radiator, shock reservoir,
etc.) may be changed, relocated or removed unless they
also serve as a strengthening member. Steering head angle
may not be less than stock rake or more than 38 degrees maximum
rake. Swing arms and struts may not be welded to frame.Struts, if used, must be "bolt on" with a maximum of (3) struts
per side. Minimum seat height, with rider in position and seat
compressed, measured from lowest point of seating position to
ground is 18-inches. Frame strengthening gussets/tubes and
replacement brackets must be made from 4130 chrome moly
steel on OEM steel frames or a compatible aluminum allow on
OEM aluminum frames. All welding must be done by using
accepted heliarc process in a "workmanship" like manner.
Frames may be polished. Wheelbase: Maximum 68-inch.
4.3.5.2.10. FRONT SUSPENSION
The use of retention straps is prohibited. Standard production
internal parts of forks may be modified to alter damping qualities.
Aftermarket damper kits or valves may be installed. Fork
springs may be replaced with optional or aftermarket springs.
Fork caps may be modified or replaced to allow external adjustment
of fork springs only. A fork brace may be added or
replaced with an aftermarket brace. Minimum required suspension
travel is 1-inch. Maximum fork tube exposure above the
upper triple clamp or clip-ons is 1 1/2-inch. A steering damper is
required.
4.3.5.2.11. FUEL
Gasoline only. All bikes must have a method to provide a fuel
sample from the fuel line system. Sample must be able to be
taken from a line between the carburetor and fuel pump or pet*****.
In fuel injected systems, the sample may be drawn from
the fuel return line between the injectors and the tank, on the
low pressure side of the circuit. At the tech inspector's discretion,
fuel samples may be taken from any location. Any Prostar
approved fuel (including oxygenated fuels) may be used, in an
unmodified state - and must pass Prostar fuel check. The use of
propylene oxide is prohibited. (See Fuel, 2.6:1,2,5 & 6.) Allow
enough fuel for a periodic two-mile ride prior to a qualifying or
elimination run.
4.3.5.2.12. FUEL SYSTEMS
Artificial cooling or heating systems, i.e.; cool cans, ice, freon,
whippets, etc. prohibited. Circulating systems, not part of OEM
fuel pump system, prohibited.
4.3.5.2.13. SEAT
Custom seats with a step to prevent the rider from sliding backwards
are recommended. Seat, tail section, and rear fender may
be incorporated in one unit.
4.3.5.2.14. TIRES & WHEELS
DOT motorcycle street tires only, slicks prohibited. Rear wheel,
up to 18-inch diameter. Front wheel, up to 21-inch diameter.
Wheels constructed of carbon fiber or carbon composite are
prohibited.