O.S. SPEED R21 Shimo Edition 3 Combo Set | TR03 EFRA 2196 + MR05

O.S. Speed R21 Shimo Edition 3 Combo | TR03 + MR05

O.S. Engines introduces the latest evolution of its 1/8 on-road competition engine: the new R21 Shimo Edition 3. Developed in collaboration with team driver Takaaki Shimo, this engine introduces key changes to the crankcase and liner to offer more linear behavior and increased longevity.

To maximize performance right out of the box, this Combo Set includes the TR03 (EFRA 2196) tuned silencer and the MR05 manifold.

New Features

• Linearity Adjustment (Spacers): The main innovation lies in the exhaust section of the crankcase, designed to accommodate spacers (included). This allows the driver to modify the engine's character, achieving a smoother and more linear response from low RPM to top speed depending on the track.
• New Internals (9 Ports): Features a redesigned 9-port liner and a piston with a new surface treatment that reduces friction and increases the assembly's lifespan.
• Stabilized Carburetor: To prevent leaks and air intake, it uses a new "Dust cover ring" that ensures a stable idle and precise tuning.
• "Shimo Spec" Components: Includes a reinforced "R" type connecting rod (based on the R2106), ceramic rear bearing, and a new "Deep Gold" outer head with matching venturi for improved heat management.

Technical Specifications

• Displacement: 3.49 cc / 0.213 cu.in.
• Practical RPM: 4,000 - 45,000 r.p.m.
• Output: 2.80 ps / 2.76 hp @ 35,000 r.p.m.
• Bore / Stroke: 16.08mm / 17.20mm.
• Weight: 347g.

Combo Content

• O.S. SPEED R21 Shimo Edition 3 Engine.
• Complete Exhaust: Tuned Silencer TR03 (EFRA 2196) + MR05 Manifold.
• T-RP7 Turbo Glow Plug.
• Reducer (Venturi) φ8.5.
• Accessories: Exhaust seal, dust caps, and spacers.