Lamella of valves competition BOYESEN motorcycle YAMAHA RD 350cc, 400cc, C / D / E / F / G and S from 1973 to 1980

Here are the famous valves BOYENSEN competition. These valves are made for the engine that equips the 350cc ET 400cc 4-stroke YAMAHA RD machines.

It will allow an increase of the power but also of the couple! This is a patented double-slat system, a thinner for low revs and a thicker one that goes into action (resonance) for high revs! The fiberglass that designs them is of very high quality! Ideal for equipping your machines unbridled and equipped.

Mounts on :

Yamaha RD 350
Yamaha RD 400
Yamaha RD 400 C / D
Yamaha RD 400 E / F / G
Yamaha RD 400 S