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10 Posts
As a red blooded american veteran who loves his Japanese machinery I am not going to touch this one with a ten foot pole, but to clarify what exactly I am not touching: AMA superbike, NHRA pro stock bike, and now this class where we have at least a fifty year head start.

2 Posts
The post is incorrect.

Mark Underwood did not even attend the World Finals.

He was disqualified after a tear-down in the previous race at Montgomery, AL. His valve angles were changed to allow larger valves.

He admitted, and all points for the season were taken away.

I was there, and I know he did not qualify with a 9.75, that was at a previous race this season.

Vince Woska

1,459 Posts
Re: New Triumph

Yeah, I saw this yesterday on a couple of other sites. Looks like a really cool bike (hey KPaul -- what do you think -- its an inline 4, but its not Japanese ;-) )

Looks like Triumph is going the same way as the Japanese in this market -- producing 2 distinct models, one cutting edge and the other more broad spectrum.

From the press release I read, I got the impression that Triumph intends this bike to be race-competitive. Does this mean we might see some factory supported race teams?

I will be interested to see how all the new crop compare. Some pretty exciting new products in this segment this year.

Looks like 600 supersport may be the series to watch this year (other than MotoGP, that is).

The Toad
17,458 Posts
Well ,where are all the obligatory comments deriding Yamaha, a manufacturer of obsolete air-colled pushrod bikes? Oh wait. Air cooled pushrod engines are not an outrage if they are produced by the Japanese.

So sorry. Please excuse me.

780 Posts
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: CLASS REQUIREMENTS 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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


89 Posts
'Gotta wonder..

'Might be a bit of (big) manufacturers' "political" influence involved here.. but then again, maybe not... It seems the rules were "clarified" periodically (or at least I was given to understand so...).

I know of a (privateer)Confederate Hellcat that was not allowed to play (113"/1857cc evo was standard - but the rules committee? disallowed a de-stroked version @100"/1640cc); and, the bike was too light @497# dry... the 155# pilot would have to add 100# of plate-weight to meet the weigth minimum. I can't help but think it might have been interesting.

1,670 Posts
Re: 'Gotta wonder..

The answer to why is right here:

"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."

The engine in a Hellcat is not in that cc range in a production state, nor is it specifically designed for the bike it is used in, so it very clearly is illegal. No argument is possible here.

The Warrior is also too light- they add weight too. Check out that metal plate underneath the engine.
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