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GENERAL ENGINE DESCRIPTION
The PRD 125cc Fireball engine is a “TaG” (Touch and Go) style engine. This engine is a
hobby engine and designed only for closed course racing on tracks built for this specific
purpose. The engine is a single cylinder 2-stroke.
Piston & Ring Single ring piston with an L-type cast iron & chrome plated ring.
Cylinder & Cast aluminum alloy.
Crank Case
Crank Case Liner The cast iron liner is fully machined then cast with an aluminum water
jacket creating a tamper proof locking system which ensures proper
alignment and stability.
Head The head is cast aluminum and fully machined on the combustion side
and attached to the cylinder with four (4) studs.
Crank Shaft Made of alloy steel machined, hardened and ground to exacting
specifications. The crank is supported in the case by C6305 ball bearings.
The connecting rod is investment forged for accuracy and durability.
Ignition Fully digital with a CDI ignition module, solid state relay and the rev
limiter preventing RPM’s in excess of 16,000. It is made for easy use and
great starting ability.
Bendix & Gear Engages the starter ring gear to start the engine.
Clutch The clutch is designed so the clutch gear may be easily changed to
achieve required gear ratios. The ring gear is part of the low stall dry
clutch that requires no adjustment. The ring gear/flywheel is part of the
clutch assy.
Carburetor HL-360A or HL-395A/HL-166 manufactured by Tillotson. Both are
diaphragm style with built in fuel pump, fully adjustable high and low
speed needles which can be set before starting the engine off the track.
