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The O.S. SPEED R2104 is a factory tuned engine solely developed for 1/8 racing competition. This new engine boasts 9-port piston liner to improve torque in low-middle power range. It also produces enough power as designed even for high traction tracks. The redesigned crankshaft counter weight enables smooth power transition from low to top. Distance of each fin of the heat sink head is enhanced for better air flow for cooling and better balance. The heat sink head is anodized in both black and red for a high contrast and powerful aesthetic.
Video Overview
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Cylinder Liner
This new engine boasts a 9-port piston liner to improve torque in low-middle power range. It produces enough power as designed even for high traction tracks.
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Outer Head
Distance between the cooling fins is enhanced for better air flow and better balance. The heat sink head is anodized in two colors: black and red.
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Inner Head
A silicon O-ring fit to the inner head prevents dust from coming into the engine.
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Crankshaft
The redesigned crankshaft counter weight enables smooth power transition from low to top.
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Carburetor
The carburetor is 21M2(B), which has been proved to be consistent and reliable for generations (R2101, 2102, 2103)
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Product Specifications
Specs
Crankshaft Threads | UNF 1/4-28 |
Crankshaft Type | Threaded |
Cylinders | Single |
Carb Type | Slide valve |
Bore | 16.08mm (0.633" ) |
HP | 2.8 ps / 2.76 hp at 35,000 RPM |
Plug Type | OS RP7 turbo, cold heat range |
Product Height | 91.2mm (3.6"), total height |
Product Length | 94mm (3.7") backplate to of crankshaft |
Product Width | 45mm (1.8") at mounting tabs |
Recommended Fuel | 10 - 30% nitro content, 20% recommended for break-in |
RPM Range | 4,000 - 45,000 |
Starter Type | Bump |
Stroke | 17.20mm (0.677" ) |
Cylinder Type | Nine port liner |
Displacement | 3.49 cc (0.213 cu in) |
Engine (Only) Weight | 340g (11.99oz) |
Power Type | Glow |