OS Max-21Tm (T-MAXX)W/11K Carb.

The OS Engines Max‑21TM nitro engine (SCH‑OS12240) is a .21‑class unit supplied with an 11K carburettor and the M‑1020 exhaust manifold as standard. OS Engines notes this model was especially designed for the Traxxas T‑MAXX; therefore, suggested compatibility includes the T‑MAXX monster truck.

With 3.41cc displacement and an output of 1.8ps/1.77hp at up to 29,000 r.p.m., the Max‑21TM offers strong performance across a practical operating range of 3,000–35,000 r.p.m. A 17.0mm bore and 15.0mm stroke contribute to balanced power delivery, while the engine’s 243g weight helps keep overall mass in check.

Built on OS Engines’ .21 platform, this variant pairs the noted performance figures with the included M‑1020 manifold for the intended application. The package is identified by part number SCH‑OS12240 and is supplied with the 11K carburettor as indicated.

Suggested Compatibility

• Traxxas T‑MAXX (as referenced by OS Engines)

Included

• M‑1020 exhaust manifold (standard accessory)

Key Specifications

• Displacement: 3.41cc (0.208 cu.in)
• Output: 1.8ps / 1.77hp @ 29,000 r.p.m.
• Bore: 17.0mm (0.669 in.)
• Stroke: 15.0mm (0.591 in.)
• Practical r.p.m. range: 3,000–35,000 r.p.m.
• Weight: 243.0g (8.58oz.)