Designed to achieve the easiest operation and max performance over & over, the new PRO-21BX-R delivers an awesome raw power & durability !
The new webbed reinforced compact crankcase is made for added wearing resistance and provides effective heat dispersion for longer runs.

All PRO series engines are manufactured by automated computer-controlled machinery, using the highest quality materials and state-of-the-art CNC manufacturing techniques to deliver a powerplant that looks and performs better. Precision mixture control carburetor makes adjustments simple, the crankshaft is lightened, and balanced to achieve a smoother and more efficient fuel mixture. 
The new 21 engine fits in the same mounting as the original .21/.28 engines, with no additional weight - but delivers greater output and higher practical rpm.

The Pro-21BX-R is equipped with a built-in recoil starters ("X" type) for easy and quick start.