O.S. SPEED 21XZ-B Features

Race-winning power characteristics

パワー特性

A tried and true 3-port sleeve design (3 bypass ports, 1 exhaust) provides smooth, crisp acceleration with a combination of specially designed inner head and sleeve porting for SPEED version. Fuel mileage is improved by 8%*

* The result of internal testing in comparison to the previous model. Test results may vary depending on the conditions of use.

Outer head

アウターヘッド

The low-gravity, black-anodized outer head with original laser marking has many cooling holes for improved cooling and extra weight reduction. The entire height is 9mm shorter than the previous model. The low-gravity head contributes to steady car control. A highly popular P3 glow plug is included.

Carburetor

キャブレター

A newly designed 21J2(B) carburetor includes 6, 6.5, and 7mm aluminum venturis. Even the smallest 6mm venturi doesn’t change its easy tuning characteristics.

Ceramic ball bearing

セラミックスボールベアリング

The black anodized crankcase adds a ceramic ball bearing in the rear to reduce rolling resistance.

Crankshaft

クランクシャフト

The intake passage is filled with silicone and ensures better fuel mixture flow. A tungsten insert is pressed in the counterweight to optimize inertia mass. DLC coating is applied to minimize frictional loss as well as improve durability.

TOP