According to the critics, Suzuki’s Z400 would be at disadvantage in the pro ranks for 04’. Leave it to Yoshimura to prove them wrong. Suzuki has won an astonishing all but one pro Motocross overall the season using a Yoshimura built engine that features their 450cc big bore kit. This kit features a 92mm forged aluminum piston, sleeve re-plating, 5mm offset crank pin and special head and base gaskets. This engine kit works great with Yoshi’s Pro Series Titanium exhaust system, and is currently used by Team Suzuki pro riders Doug Gust and William Yokley.
Yoshimura Research and Development
5420 Daniels St.
Chino, CA 91710
Phone - (909) 628-4722
Fax - (909) 591-2198