It is a long-stroke engine, bore x stroke is
16.27 x 16.80mm. It has quicker response in low range and more torque
in middle range with consistent idling.
- The new piston/liner is conventional 3-port type enabling more torque over the power range.
- The new crankshaft has DLC coating as we always do for OS SPEED engines.
The two tungsten counterweights are embedded in the crankshaft
contributing consistent idling and quick rpm down according to throttle
- The thrust plate with surface treatment embedded in the cover plate
reduces friction against a connecting rod to extend its life.
- The boost port and the exhaust port of the crankcase are redesigned for optimum air flow.
- The carburetor is trustable 22E type, which we have been using for B2103 Type R.
- The cooling head is conventional round-shape type with standard height.
- An o-ringed inner head, which absorbs vibration and prevents dust coming into the combustion chamber.
Displacement:3.49cc / 0.213 cu.in.
Bore:16.27mm / 0.641 in.
Stroke:16.80mm / 0.661 in.
Output:2.68 ps / 2.64 hp / 34,000 r.p.m.
practical rpm range: 4,000-42,000 r.p.m.
weight:352g / 12.42 oz.
Glow plug T-P3 ·Reducer f6??f6.5?· Exhaust seal ring
Dust cap set 12-30(f3?f16?f18)