O.S. SPEED B2105 radio-controlled heat engine (engine only)

O.S. SPEED B2105 radio-controlled heat engine (engine only)

Based on the O.S. SPEED B2104, the crankshaft and sleeve/piston assembly are new.

Power output is higher.

Compared with the B2104, it has more torque at medium and high rpm, and lower torque at low rpm, making it easier to use than the B2104.

Handling is improved by reducing the weight of the cylinder head.

For optimum performance, the newly designed crankshaft features revised timing and counterweight balancing, as well as the traditional O.S.SPEED DLC coating.

With the new crankshaft, power is very linear and you get power at any rpm without any constraints.

Liner: The shape of the exhaust port has been revised to improve performance.

The carburetor is based on the 22E with an improved idle adjustment needle. Fuel delivery is more stable.

A surface-treated thrust plate integrated into the crankcase cap reduces friction against the connecting rod and extends its life.　

The rear bearing is now ceramic.

Technical specifications:

• Displacement: 3.49cc
• Bore : 
• Stroke :
• Power output :
• Rev range :
• Weight :

Accessories included :

• Turbo P3 spark plug
• 6mm diameter venturi
• One 6.5mm diameter venturi
• Three plugs: 3; 16 and 18mm
• One exhaust gasket