O.S. Engines R21 1/8 On-Road Club Racer OSM1B900

This is the O.S. Engines R21 engine for 1/8 scale on-road club racers.

Includes:

• R21 Engine with 21M2 Slide Valve Carburetor
• RP7 Turbo Glow Plug
• 8.5mm Carb Reducer Dust Cap Set
• Instruction Manual

Requires:

• Fuel: Car blend, 25% nitro content recommended for break-in
• Exhaust System depending on vehicle
• O.S. Engines T-2080C Tuned Silencer Set (OSMG2983)
• Glow Starter
• Track Equipment

Features:

• Nine fin anodized aluminum cylinder head in blue
• 21M2 slide valve carburetor with 8.5mm reducer
• Silicone filled crankshaft

Specs:

Displacement: .213 cu in (3.49 cc)
Bore: 0.633 in (16.08 mm)
Stroke: 0.677 in (17.2 mm)
Output: 2.75ps / 2.71 hp / 32,000 RPM
Weight: 12.35 oz (350 g)
Practical RPM: 4,000-44,000
Crankshaft Size: UNF 1/4-28
Distance between Mounting Hole Centers Same Side: 0.83" (21mm)
Distance between Mounting Hole Centers Opposite Side: 1.4" (37mm)
Height Bottom of Mounting Tab/Top of Cylinder Head: 3" (75.6mm)
Height Bottom of Crankcase/Top of Cylinder Head: 3.6" (91.2mm)
Height Bottom of Mounting Tab/Exhaust Outlet Center: 1.1" (28mm)
Length from Cover Plate to Front Bearing: 2.5" (64.5mm)
Length from Cover Plate to End of Crankshaft: 3.7" (94mm)
Length from Cover Plate to Center of Crankcase: 0.81" (20.5mm)|
Length from Crankcase Center to Front Bearing: 1.7" (44mm)
Length from Crankcase Center to End of Crankshaft: 2.9" (73.5mm)

Carburetor Settings

• Needle Valve: 3 turns open from fully closed
• Mixture Control Valve: Flush with carburetor body, adjusting range within +- 1 turn
• Metering Needle: Standard position, flush with ball link body
• Throttle: Approximately 0.5mm open from factory setting with reducer removed