OS Engines Speed R21 Euro II .21 Nitro On Road Engine

O.S. Engines have introduced their updated version of their R21 Euro 1/8th On-Road Nitro engine with the R21 Euro II. It inherits the smooth and easy-to-use feeling of its predecessor, with new features to improve performance.

Features

• Updated laser graphics on the cooling head
• High cooling performance and lightweight outer head
• O-ring embedded inner head
• Comes with 21M2 (B) carburettor, which is popular with many racers for maximum performance
• The cylinder with 7 ports and piston have a new design with cooling holes added to the bottom of the exhaust with the newly designed crankcase

Product Information

The OS Engines R21 Euro II Nitro On-Road Engine features some upgrades to improve performance. To obtain more power the balance of the crankshaft was updated and now sports 3 tungsten counterweights, giving an improvement in the mid-range. Another effect of this change is the return to idle has been improved. The liner now has an additional cooling hole on the exhaust side and the crankcase has been updated to cater for this. The OS Engines Speed R21 Euro II Engine is available on its own or as a combo with the TR01 pipe and MR02 manifold.

Specs

Displacemen 3.49 cc / 0.213cu.in.

Bore 16.08 mm / 0.633 in.

Stroke 17.20 mm / 0.677 in.

Output 2.8 ps / 2.76 hp / 35,000 r.p.m.

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

Weight 340g / 11.99 oz.