Back in January, the Thumper Racing crew re-jetted a Yamaha Grizzly 660 4x4 for us, and they’ve grown to appreciate the five-valve utility quad for having a lot of
other attributes than just the best head design in the industry. In
true Thumper fashion, Gary Hazel and crew couldn’t leave the
Grizzly alone, and set out to make it a better trail machine.
Project Stage 2 Grizzly was born, and zeal took the project quickly to Stage 3, a full-on mudder for the many swampy East Texas
OHV parks. Now the Thumper Grizzly cruises the bogs looking for
700s and 800s to declaw.
Sharpening the muddy
claws and trail teeth