2005 NCK Local Option Class
NCK Stock CR125 Moto

The name of this class has been changed to IKF Super Stock CR125 Moto and the rules have been updated for 2006...  Click HERE, to view the revised 2006 rules.
 

Guidelines offered in these pages are subject to the term "Spirit and Intent" and apply to the technical aspects of this "Stock" sprint shifter kart class. It is expected that all participants will adhere to the spirit and intent of these rules. These are guidelines for fair and equitable competition. They are not the basis to "read between the lines" in order to circumvent the intent.

Northern California Karters (NCK) does not intend to become the center for arguing and bickering. If you are the type of person that is intent on finding loopholes, then it is imperative that you reevaluate your decision to run in this class. If you are contemplating a technical undertaking that is not directly addressed in these rules, please contact the NCK BOD to make sure it is legal and will be allowed.

Spirit and Intent: "If these paragraphs do not say you can, you can't!"

Stock Defined: All displacements will bear a tolerance that will be defined by specifications deemed as "Factory Stock," in specifications from said manufacturer. All post event technical inspection will rely on published factory specifications.

Neither the OEM engine nor any of its auxiliary components may be modified in any way, unless an exception and / or exclusion is specifically noted within the rules. This includes the addition, deletion and / or omission of and / or adjustment to parts and / or materials. Note: Adjustments to components that are specifically designed for that purpose shall not be construed to be a modification (i.e. Carburetor jets, needles, slides, adjustment screws, spark plugs, exhaust flange spacers, etc.).

OEM Defined: For purposes of defining allowable engine components, OEM will mean parts produced by a particular manufacturer for a particular model. Where OEM parts are called out for example, you may not use Yamaha parts in a Honda engine, or Honda RS parts in a Honda CR engine. Except where otherwise stated, the year of manufacture is open, provided the parts are commercially available in the U.S. market.

Chassis: Same as IKF 312.7.1.1

Brakes: Same as IKF 312.7.1.2

Bodywork: Same as IKF 312.7.1.3

Tires: Same as IKF 312.7.1.4

Engine: Stock OEM Honda CR125.

Top End: Cylinder and cylinder head must be stock 1999 OEM Honda CR125. Exception(s): Power valves must be removed and the power valve ports plugged (power valve plugs may be modified to achieve desired fit). The power value actuator rod hole must be plugged. Machining of the mating surface of the cylinder head only, between the cylinder and the cylinder head, is allowed. Minimum 11.0 CCV, measured with a L.A.D. tool (part #CCMP).

Head gasket and base gasket must be stock OEM. Exception: An additional .010 base gasket may be added.

Piston, ring, wrist pin and upper rod bearing must be stock OEM. Exception: For the purpose of cooling / lubricating the exhaust bridge, up to a maximum of three holes may be drilled (1/16 inch maximum diameter), in the exhaust side of the piston.

Bottom End: Crank, rod and flywheel assembly, including bearings and seals, must be stock OEM.

Intake System: Box stock PWM or PWK 38mm carburetor. Bore may not exceed 38.6mm in diameter, through the .400" long throat, measured inboard (engine side) of the slide. Exception: Pump around fuel recirculation system is allowed.

Single, pulse type pump feed system. One (1) pump feed only. Any additional pump must be for evacuation (i.e. pump around system). No belt driven pumps.

Intake manifold and reed assembly must be stock OEM. Exception: Single-stage (single plane) aftermarket reeds are allowed.

Ignition System: CDI, spark coil, wiring and connectors must be stock 1999 OEM. Kill switch, if used, must function only to kill the engine.

CR125-Honda part number #xx-xxxx (1999)

Note: NCK reserves the right to require a competitor to swap ignitions, prior to the start of a race event. Failure to comply will result in DQ for the day.

The stator and flywheel must be stock 1999 OEM. Exception: Modifications to change the static timing are allowed, by modifying or removing the flywheel key.

The spark plug manufacturer is open, but must be commercially available and without modification. Exception: The gap of the electrodes may be adjusted and the washer may be removed.

Exhaust System: Use of a spec pipe is required. The spec pipe must be manufactured to the exact specifications as the R.L.V. Honda R2 pipe (R.L.V. part #6800) and may not be modified. Spacers are allowed, between the cylinder and the exhaust flange.

10.12.04: Per R.L.V. - Discontinue using "R2," when referencing the spec pipe. The spec pipe must be manufactured to the exact specifications as R.L.V. part #6800 (a one-piece stamped pipe) and may not be modified.

Exhaust silencer is open, but will be at least 12 inches in length and at least 3 inches in diameter (minus 10% tubing tolerance). Silencer core must be perforated for a minimum of 10 inches in exposed length, with 1/8 inch or larger diameter holes, on a 3/16 inch staggered center pattern. The silencer core may not exceed 1-1/4 inches inside diameter and must be wrapped in fiberglass or steel wool.

O-ringed aftermarket exhaust flange allowed (40mm inside diameter plus or minus 0.5mm). Note: Removal of carbon build-up from the inside of the exhaust flange will not be deemed to be a modification.

Transmission / Clutch: Components must be stock OEM. Exception: Finish on gears is a non-tech item (gears may be tumbled). Aftermarket clutch springs, discs and plates are allowed.

Shifter must be a manual mechanical apparatus.

Note: While air / electric / pneumatic shifters are not allowed, this restriction may be waived to accommodate special driver needs and requires prior written approval by NCK.

Intake Noise Suppression: Air boxes are required, only when local authority mandates. Use of a bolt-on air filter adaptor is allowed.

External Modifications: Cases must be stock OEM. Exception(s): Kick-starter assembly may be removed and the hole plugged. Cases that have had the kick-starter hump removed are currently legal, but will be phased out over the next several years. A hole may be drilled and threaded to accommodate a pulse line. The case may be clearanced to accept a larger front drive gear.

Other: OEM water pumps must be retained. No axle or external water pumps allowed. Cooling system may use only water and / or water based coolants. Catch containers and / or alternative plumbing is mandatory, to deal with potential carburetor and radiator overflow. Chain guards are required.