O.S.Speed R21GT Engine

Features:
5-scavenging port + 3 exhaust port design is conforming to IFMAR regulation
DLC coated, Silicon filler, double counter weights for powerful torque and response
New carburetor 22E(B)GT: Double adjust type, smooth acceleration from cornering
Specifications:
Bore: 
0.633" (16.08mm)
Carb Type: 
Slide Valve w/7mm Restrictor Installed
Crankshaft Threads: 
UNF 1/4-28
Crankshaft Type: 
SG
Cylinder Type: 
Five Scavenging Ports, three Exhaust Ports
Cylinders: 
Single
Displacement: 
0.213 cu in (3.49cc)
Engine (Only) Weight: 
13.2oz (369g)
HP: 
2.65ps, 2.61hp @ 34,000RPM
Height: 
Bottom/Mounting Tabs to top of Cylinder Head 3.4" (86.5mm)
Length: 
Backplate to Front Bearing, 2.5" (64.6mm)
Oil Type & Content: 
12-16% Synthetic Oil Mixture in Fuel
Plug Type: 
RP6 Turbo Type, Medium Heat Range
RPM Range: 
4,000 - 42,000
Recommended Fuel: 
10-30%, 20% Nitro Content for Break-In
Stroke: 
0.677" (17.20mm)