This is the Ofna Jammin' .12 Rear Exhaust Off-Road Engine without Pull Starter.
Ideal for the Ofna CRT.5 Mini Truggy.
FEATURES: ABC construction "A"luminum piston with "B"rass liner that is
Three port liner, bushing equipped connecting rod
Ball bearing-supported crankshaft
Composite bodied Slide Valve Carburetor with Red silicone boot
Red anodized aluminum cooling head
SG type balanced crankshaft
INCLUDES: Ofna Jammin' .12 Rear Exhaust Off-Road Engine, drive hub and parts
REQUIRES: Fuel: 20% nitro
Glow Plug: Hot heat range, OSMG2691
Glow Starter and track equipment
SPECS: Needle Settings;
Needle Valve: 3-3½ turns from closed
Low Speed Needle: 5 turns out from closed, do not adjust until
needle valve is properly set for power and top speed
Barrel Stop Screw: 1/16" gap to start new engine, open more for
Bore: .54" (13.80mm)
Stroke: .55" (14mm)
Displacement: .12 cu in (2.1cc)
Claimed Horsepower: 1 HP
Weight: 7.7oz (220g)
Width between mounting holes same side: .43" (11mm)
Width between mounting holes opposite side: 1.2" (32mm)
Crankcase width below mounting tabs : .98" (25mm)
Distance from coverplate to drive hub: 2.7" (69mm)
Distance from coverplate to end of crankshaft: 3.2" (81mm)
Height/bottom of crankcase to top of cylinder head: 3.5" (88mm)
Height/bottom of mounting tabs to top of cyinder head: 2.9" (74mm)
COMMENTS: For pull start version order OFNG5125.
Some points on Slide Valve and Rotary Carburetors-
Rotary Carbs offer a larger response in the middle of the engine's
power band. This is desirable for off-road applications where
throttle response must be varied.
Slide Valve Carbs provide greater response at the beginning and end
of the power band. This works well for on-road and racing vehicles
demanding fast take-offs and high speed.