RIVERSIDE RACEWAY PARK CLONE RULES FOR 2010

Revised as of MARCH 31, 2010

ENGINE SPECIFIC TECH SHEET FOR: BOX STOCK PROJECT 6.5 OHV

 

DESCRIPTION: Single cylinder, 2 valve, OHV 4 cycle

Important Note: All parts must be Box Stock Project factory production parts unless otherwise specified in this rules manual. No machining or alteration of parts is allowed unless specifically noted. All parts will be subject to a comparison to a known Box Stock part.  When performing a comparison check a  + /- .005” tolerance will be used unless otherwise indicated.  Engine will be teched as raced. Engine must be one of the Blue or Yellow Harbor Freight motors.   No Honda GX series motors

 

CLAIMER RULE: There will be a $225 claimer rule in place for this engine. You must finish the race in the box stock class to purchase the winners engine.  – If you finish 4th, for example, & you want to purchase the winners’ engine, you must also purchase the 3rd & 2nd place engines as well. Claimed engine does not include the clutch, chain guard, throttle kit, header pipe/muffler, air filter adaptor and air filter, top plate, fuel pump, and valve cover with pulse fitting. The seller must supply a stock valve cover to the claimer. Any claim or protest must be filed in the scale area within 5 minutes after race is completed. $100 to protest, $50 to accept. Once  protest monies are given to track official  you must complete the protest. No exceptions.

 

Refusing to accept the claimer (1st Offense) will result in immediate disqualification of competitor along  with   forfeiture  of  any  points   earned  to  date  in the class. ( 2nd Offense),  driver and/or kart owner will not be allowed to compete any longer in that class.

 

There will also be a $25 tech in place that will consist of lift check, spring check and carb check. This tech will be performed on the grid impound area after the feature race. See below for additional tech options.

 

If karter denies tech, he/she will be disqualified  Any arguing with track official, use of inappropriate language, or causing a disturbance will result in an immediate suspension of not less than 2 weeks and a $500 dollar fine paid to the track before returning. A disturbance includes pushing or bodily contact with a track official or competitor.

 

COMBUSTION CHAMBER VOLUME:  27.5 cubic centimeters minimum, with piston at TDC, using prescribed procedure.

 

 CYLINDER HEAD REQUIREMENTS: Must be OEM casting only. Porting and/or grinding are not permitted.  Valve seats are two angles 45º valve face and 30º top relief. Stock head bolts only, must have four. Head gasket may be after market; must be of stock configuration. No copper or aluminum gaskets allowed.  Any stock configuration gasket allowed; no other sealer permitted.

 

BORE AND STROKE: Stock cylinder bore is 2.685” max.   Stroke is 2.123” +/- .005”.

 

 

 CARBURETOR : Huayi OR RUI*ING model carb only.  Carb to intake sealer must be  gasket only, no other sealer allowed.  Choke is optional.  Choke bore: .810 NoGo. Stock emulsion tube only without modification.  Venturi: .615 NoGo. Rear carb bore: .751 NoGo.    Main fuel jet: .042 NoGo.  Small Fuel jet: .019 NoGo.  Stock air cleaner assembly or optional aftermarket airhorn/adapter and “Clamp On” air filter.

 

 CARBURETOR/FUEL TANK REQUIREMENTS: Floor Mounted fuel tank or stock tank (optional).  Pulse type fuel pump allowed.  Fuel pump must be pulsed from either the side cover, valve cover, or block. You may install a flat metal plate or equivalent support in the original tank location for the purpose of mounting the throttle linkage and fuel pump.  Pump gas only, 87-93 octane. No racing fuel or power additives.  Gas will be teched with hydrometer at end of race. We reserve the right to send any suspicious fuel sample to the lab for further testing. No pay out will be made until the lab result is known.

 

 VALVE TRAIN: Stock valve cover only with any stock configuration gasket. Factory stock rocker arms,  (no modified ,extra ratio arms allowed). Factory stock push rods only. Stock valves only,  45º degree angle only  (both valves), no modifications allowed. Single wire valve springs:  Dyno Cams white stripe valve spring, part number DCS-CL1 or equivalent. Valve spring must test at 18 lbs. max at .900 installation height.  Wire diameter.:  .099 + .005 max.     

 

IGNITION SYSTEM:  Stock Box Stock system only and must be unaltered. Kill switch and low oil sensor may be disabled and removed.

 

 FLYWHEEL: Box Stock flywheel only with plastic fins. No alterations of any type allowed. Must also run stock flywheel key, no advance timing allowed.

 

 PISTON & RINGS: Must be unaltered Box Stock only.  No machining of piston and rings allowed. 

 

 CONNECTING ROD:  Box Stock rod only. No billet rods.  No machining of any type allowed. Stock rod bolts only.

 

 CRANKSHAFT REQUIREMENTS:  Box Stock crankshaft required.   Machining, polishing, addition of material or other alteration of crankshaft is prohibited.  Stock factory timing gear mandatory and must be installed in original

location.  Crankshaft journal diameter is 1.180”- 1.175” min.

 

 

 

 

CAMSHAFT REQUREMENTS:  Stock as cast camshaft only, must still have compression release functional.  

Intake lift on cam .225” max taken at the pushrod.

Intake lift at the valve .238” max taken on valve spring retainer with zero lash.

Exhaust lift on cam .232” max taken at the pushrod.

Exhaust Lift at the valve .242” max taken on valve spring retainer with zero lash.

 

Cam Profile  (+/-3 degrees)

              Intake

 

050 Lift 8 ½  degrees   ATDC

.100 Lift 26   degrees   ATDC

.150 Lift 47   degrees   ATDC

.200 Lift 75  degrees    ATDC

Max lift taken at pushrod .225

.200 Lift 32  degrees    BBDC

.150 Lift  4   degrees     BBDC

.100 Lift 16  degrees     ABDC

.050 Lift 34 degrees     ABDC

.010 Lift 72 degrees     ABDC

 

              Exhaust

.010 Lift 76  degrees    BBDC

.050 Lift 28 degrees    BBDC

.100 Lift 11  degrees     BBDC

.150 Lift 8   degrees     ABDC

.200 Lift 33 degrees    ABDC

Max Lift taken at pushrod .232

.200 Lift 65 degrees    BTDC

.150 Lift 37 degrees    BTDC

.100 Lift 17 degrees     BTDC

.050 Lift 0  TDC

.010 Lift 40 degrees    ATDC

 

Special note. Valve guide wear can give false valve lift readings when checking off the front of the valve spring retainer. It is advised to take readings at several  points around the retainer (back, and both sides) if wear is suspected of giving a false, unfavorable reading.

 

BLOCK REQUIREMENTS:  Block must remain stock as produced. Stub for governor may be removed and hole plugged.  No machining of block allowed. Block may be honed when installing new piston rings. Must use stock piston. Welding to the block shall be for rod damage repair only and may not constitute a functional modification.  Deck Height: .000.

 

HEADER & MUFFLER REQUIREMENTS:   Any single stage, one piece header made of steel tubing allowed.  All headers must be wrapped for safety.  WKA muffler (stock style only) NO MODS, no limited style “open hole” muffler allowed. Muffler must be clamped and strapped with positive fasteners. No welding permitted.

 

CLUTCH/GEAR RULE: Open Clutch (any manufacturer). OPTIONAL-- RUN 19 tooth clutch sprocket and 72 tooth rear sprocket---OR 18 TOOTH/68 TOOTH REAR.  (19/72 OR 18/68).  MARCH 31, 2010.

 

TIRE RULE:  BURRIS B33A ONLY.    42 DUROMETER MINIMUM.

 

SEALED MOTORS: We will have a sealed motor option that will cost an extra $30. Must contact tech official, who will check engine for any modifications.  If tech is legal, the motor will be sealed at head, block, and side cover. With regard to sealed motors from other tracks:  Riverside Raceway tech will still apply as if motor has never been sealed, to include the $225 claimer rule.

 

 

$25 TECH.  (On track at impound area). Valve springs, carb check, rocker arm check and lift check. Tech official gets the $25.

 

$50 TECH.   Entire motor tech, block, head, cam, crank, piston, rod, and carb. (This option applies to making an appointment with the tech official during the week, prior to race night, or leaving your motor with the tech official after the race, to be picked up at a mutually agreeable time, in order to determine compliance with track rules) Tech official gets the $50. 

 

$30 SEALED MOTOR OPTION.   Inspection of new motor (unopened box) in the tech room. (This option not available on race night). You must make an appointment with the tech official. Tech official will seal the block, head and side cover.  Includes seals and new side cover gasket. Removal of governor shaft and installation of governor shaft hole plug extra.

 

RIVERSIDE RACEWAY (STOCK APPEARING) BLUE OR YELLOW CLONE

 

STOCK APPEARING  Blue or Yellow 6.5 OHV Single cylinder 2 valve 4cycle motor.

Motor and carburetor may be modified internally. Must run billet rod and flywheel. After market header and RLV muffler. Methanol may be used as fuel.

ANY AND ALL RULES SUBJECT TO CHANGE AT ANYTIME