Engine	F- 91S
Displacement	14.97 c.c. / .914 cu.in.
Bore	28.3 mm / 1.114 in.
Stroke	23.8 mm / 0.937 in.
Practical R.P.M.	2,000 ~ 12,000 rpm
Output (BHP/RPM)	1.6 / 11,000
Weight (g/oz)	742.8 / 26.20

Thunder Tiger new F-91S powerhouse engines is the perfect way to enjoy the advantage of four-stroke performance; the ability to swing a large prop, increase torque, reduce noise and improved fuel economy. Feature with the twin needle updraft carburetor, black anodized cylinder head, oversized valves, combined with a high performance silencer to have the best power-to-weight ratio.

Black cylinder head.
Crankshaft with Ni plating to reduce corrosion.
The XC2 (extreme composite coating) cylinder liner with special criss-cross pattern etched.
Lightened hyperutectic machined Al-Si ringed piston.
High strength connecting rod with bushings pre-installed.
Over-sized drive washer diameter for 13” to 18” propeller.
Dual ball bearing supported crankshaft.
Rubber- sealed rear bearing to reduce corrosion.
Plain bearing supported camshaft.
Fine polishing rocker cover.
State of the art CNC machined components.
Smooth manifold.
Rear-mounted up draft and Reversible carburetor.
Black anodized muffler included.
Redline RF glow plug included.

1. F-91S engine x 1 EA
2. Carburetor Assembly x 1 EA
3. Allen wrench 3mm ＆2.5mm ＆2mm ＆1.5mm
4. Wrench 5/5.5 ＆12/14
5. Muffler Assembly x 1 EA
6. REDLINE RF glow plug x 1 EA
7. Instructional manual x 1 EA
8. TT logo sticker x 1 EA

Instruction Manual
Parts Catalog