"Baby Blues" Champ
Engine Rules 

Engine:  The class will run the 79cc predator engine out of the box allowing only the modifications listed below. NO EXCEPTIONS!! Below are some rules for setting up the clutch and throttle and guidelines for the engine.

 

1.  Approved Engine: OHV ( Overhead Valve) 79cc (3HP) Harbor Freight Predator Engine. ONLY

 

2.  Engine Components: Engine must be stock 79cc Predator engine with factory governor intact and functioning. 

 

3.  Low oil sensor may be unplugged or removed and block plugged if it has one (current models do not)

 

4.  You must run the factory gas tank. Gas cap may be vented

 

5.  Chain guard: is mandatory and must include a heat shield extending 1/2" inch above the muffler box but not to exceed 1" inch

 

​6.  Flywheel and Ignition: Must use stock flywheel, ignition coil, plug wire, and resistor spark plug boot. Spark plug is non tech. The engine must have the factory key-way as installed by the factory. Factory timing on the flywheel is prohibited to change.

 

​7.  Fuel: 87 octane only. No additives an No menthol

 

​8.  Carburetor: Carb MUST REMAIN STOCK

 

9.  Airbox: No alterations to the air box, Must run the factory foam filter inside the airbox. Replacement aftermarket foam filters may be purchased from Midwest Champ Kart Series. Reach out to purchase.

 

10.  Throttle System: MUST USE THE MANUAL THROTTLE LEVER (tortoise and hare) for the throttle setup. This is for your driver's safety. Carburetor butterfly must function with the governor and driver's foot only. Pictures are provided for guidance. Throttle cable must be secured with a mechanism and must work properly with the butterfly located on top the carb. Must have a properly functioning return spring somewhere in the throttle system. This system can be engineered freely to your imagination but will be inspected for safety. We have provided a simplified system in the pictures that cost less than a few dollars to fabricate. Here the one we found easiest to use. Throttle Kit, 79cc/98cc Predator Engine (79CCTK) (gopowersports.com)

 

​11.  Cylinder Head: Must be the OEM 79cc Predator type casting only. Intake and exhaust ports must remain as factory produced, porting or deburring not permitted. Transition edge from port runner to bowl area must remain defined edge. Head gasket surface must remain stock, no copper or aluminum gaskets.

 

​12.  Valve train: Stock valves only, must use stock pushrods, rocker arms, retainers and valve springs,

No alterations and or aftermarket valve train components allowed. Camshaft must remain stock.

Crank rod and piston must be as factory without any modifications, stock piston rings only.

 

13.  Starter: Recoil pull start only. Pull starter may be rotated for better cranking angle and have better quality replacement rope installed.

 

14.  Clutch: All Baby "Blues" Champs must run a shoe style drum clutch only. The clutch is open to any drum clutch 5/8" or 3/4" bore hub. The 3/4" hub clutch will require a clutch adapter. Must run 11/62 through 66 gearing. 

 

15.  RPM: There is an +-200 4100 RPM Rule. The Engine needs to go through Pre-Tech and painted on the GOVERNOR SPRING SETTING "SET SCREW". To assure the rpm does not move please use a jam nut. 

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​16.  Headers and mufflers: Must remain factory muffler in stock form only. No aftermarket headers or mufflers, no modifications to factory muffler. Prohibited to remove any of the stock bolts and drill any additional holes for better air flow