Brand Logo
5 out of 5 Customer Rating

21XR-B Version II Car Engine

Item No. OSMG2056
Brand Logo
5 out of 5 Customer Rating

21XR-B Version II Car Engine

Item No. OSMG2056
This Item is No Longer Available
Selected Store

Product Details

Powerful performance for weekend warriors.

1/8 scale buggy competition is as fierce as it gets. You want every advantage possible — and it starts with the 21XR-B Version II engine. This version of the 21XR-B power plant has been totally re-designed. It’s even more reliable, and the new 21J3-I carb is easy to tune. The aluminum cooling head ensures steady power even under harsh conditions. And when you're ready to move up to top competition, you can get up to speed with the 21XR-B Version II. This engine is upgradeable with high-performance O.S. Speed Parts, letting you realize your full winning potential. Equip your ride with the 21XR-B Version II, and start owning the podium.
  • Engineered for up-and-coming 1/8 scale buggy club racers, with upgrade capability for competing at the highest levels.
  • A dependable, low-maintenance engine that fits into most any modeler's budget.
  • O.S. Speed parts are available for updating the outer and inner heads, crankcase, crankshaft and more.
  • Includes P3 turbo plug.
O.S. 21XR-B Version II Buggy Engine - Carburetor
The 21J3-I carb comes with two intake restrictors that can be swapped out quickly and easily for fine-tuning to meet track conditions. The yellow (7 mm) restrictor gives you more bottom end, while the red (8 mm) restrictor delivers more top end.
O.S. 21XR-B Version II Buggy Engine - Cylinder Head
The blue-anodized aluminum cylinder head delivers superior cooling.

Product Specifications


Bore 0.64 in (16.27 mm)
Carb Type O.S. 21J3-I slide valve w/7mm & 8mm restrictors
Crankshaft Threads UNF1/4-28
Cylinders Single
Displacement 0.213 cu in (3.49 cc)
Engine (Only) Weight 13.40 oz (380 g)
Power Type Glow
HP 2.45 PS 2.42 HP @ 33,000 rpm
Plug Type Turbo P-3 Glow Plug
Product Height 3.4 in (86.5 mm) bottom of mounting tabs to top of cylinder head
Product Length 2.5" (64.5 mm) from backplate to front bearing
Product Width 1.8 in (45 mm) at mounting tabs
Recommended Fuel 10-30% nitro content, 20% recommended for break-in
RPM Range 4,000 - 40,000 rpm
Stroke 0.66 in (16.8 mm)
Total Weight 12.5 oz (353 g)