OS Max-R21 V2 Combo Set

The OS Engines MAX-R21 Ver.2 (SCH-OS1F401) is a 3.49cc nitro engine developed for 1/8 on-road racing and supplied as a combo set with pipe. Aimed at entry-level through to sports users, it offers excellent cost performance with updates focused on easier running and setup.

Compared with the previous model, both the crankshaft and carburettor have been revised for greater ease of use. The distinctive blue outer head, the image colour for the MAX series, now features a new laser-etched design.

Delivering 2.75 ps (2.71 hp) at 32,000 rpm and a practical operating range of 4,000–44,000 rpm, the MAX-R21 Ver.2 provides the high-revving characteristics suited to modern 1/8 on-road applications. Engine weight is 350 g.

What’s Included

• RP7 plug
• Exhaust seal ring
• Dust cap set (3 mm / 16 mm / 18 mm)
• Flywheel collet
• Reducer 8.5 mm (purple)

Specifications

• Displacement: 3.49 cc (0.213 cu.in.)
• Bore: 16.08 mm (0.633 in.)
• Stroke: 17.20 mm (0.677 in.)
• Output: 2.75 ps / 2.71 hp @ 32,000 rpm
• Practical RPM Range: 4,000–44,000 rpm
• Engine Weight: 350 g (12.35 oz)