Reader hops up his Yamaha 450 quad


Modern 450 quads like Yamaha’s YFZ450  have such high-tech engines it’s hard to extract much more power than what they come with stock. David Armitage in Illinois found a way around that rule. However, you may say he cheated when he took out the single-cylinder 450cc engine.

Instead, he installed a Suzuki GSXR 4-cylinder street bike engine in his YFZ. When those things are revving up past 10 grand they produce around 160 ponies. That’s about three times the horsepower of a stock YFZ. Yeah, that would make it even more fun to ride for sure.

Of course, the physical dimensions of a 4-cylinder street bike engine are bigger than a single-cylinder 450 engine. Therefore, it’s not just a simple drop-in installation.

As you can see from the photo David had to take a hacksaw to his YFZ frame and remove a few frame tubes. Then he had to bend and shape some new steel tubing and weld it into place around the taller and wider engine. The four exhaust pipe headers also had to be bent just right to fit into place. It takes hours of figuring, measuring and fabricating to complete the job, but when done right it’s worth the effort.  Just think of the sensation you get when going through the gears on this beast.


We know there are other project quads out there that deserve to be featured in Dirt Wheels. We’re not allowed to go around looking in everyone’s garage to find these works of art. Nope, we have to rely on you folks sending us photos and info on your prized machines. So, please do so.

Send your Emails to us at [email protected]

To subscribe to Dirt Wheels Magazine in print or digital form click here https://hi-torque.com/product/dirtwheels



Comments are closed, but trackbacks and pingbacks are open.