OS Engines Speed R2105 .21 On Road Engine with EFRA2165 Pipe

OS Engines Speed R2105 .21 On Road Engine with EFRA2165 Pipe

The O.S. Speed R2105 Engine is a factory-tuned engine developed for 1/8 racing competitions. It is based on its predecessor, the R2104 engine, and has been further improved to have an easy-to-handle feeling that can be used on any course.

Features

• This combo set includes the EFRA2165 pipe
• Based on the R2104 engine with improvements
• Performance is improved by adopting a new mould of the crankcase
• By changing the crankshaft, the counterweight from φ4 to φ4.5 and optimizing the weight balance, the feeling in the mid-low speed range is improved
• Cylinder liner - adopts 9 ports that have a good reputation in R2104. The shape has been changed to match the new crankcase
• Outerhead has been changed from conventional black colour to polished silver with clear coating
• Cover plate - a well-established thrust plate, the same as that of B2104 is adopted

Product Information

O.S. SPEED R2105 is a factory-tuned engine solely developed for 1/8 racing competitions. The new engine boasts a 9-port piston liner to improve torque in the low-middle power range. It produces enough power as designed even in high traction tracks. The redesigned crankshaft counterweight enables a smooth power transition from low to top. The carburettor is based on 21M, which was well received in R2104, the main needle was changed from one o-ring to two o-rings. This stops needle change while running the engine, making it ideal for long races. In addition, the idle adjustment valve has been changed to have more torque coming out of the engine.

Specs

Displacement .49 cc / 0.213cu.in.

Bore 16.08mm / 0.633 in.

Stroke 17.20mm / 0.677 in.

Output 2.80 ps / 2.76 hp / 35,000 r.p.m.

Practical RPM range 4,000-45,000 r.p.m.

Engine weight 345.0g / 12.17 oz.