2010 Yamaha YZ450F

Yamaha YZ450F

Ringleader: Brian Catterson
MSRP (2010): $8090
Hours: **Approx. 12
**Accessories & Modifications: Engine mapping, suspension work

It's a tad ironic that Kawasaki helped make my new long-term Yamaha better, but it's true.

When I gave back my 2009 KX450F, the one thing I regretted never doing was fine-tuning the fuel injection. That would have meant installing the accessory ECU controller behind the front numberplate and some software on my laptop, then learning how to use it. On my new 2010 YZ450F, all I needed was a GYTR Power Tuner ($279.95), which plugs into a connector behind the left radiator shroud.

Not that I did said tuning myself. At the behest of Yamaha's off-road media rep Tim Olson (formerly of the Motocross Action Wrecking Crew, the only guys besides Art Friedman cool enough to wear orange helmets), I picked up my new bike one Thursday at Glen Helen Raceway.

My YZ is the optional white/red color scheme, which comes with a gold chain and black rims, and costs $100 more than the basic blue model. It's a classy-looking unit, very Euro-chic, though I'm not big on the little "snowflakes" on the radiator shrouds and numberplates and I wonder how long it will be before the black rims get scratched.

First order of business was tailoring the ergos to fit my 6'1" frame. Moving the eccentric bar clamps to their optional mounting holes put the Pro Taper handlebar in the second most forward position. To move it to the first, I'd just need to rotate the clamps.

R&D; tech Jonathan Belding brought along a spare set of fork legs and a shock with stiffer springs (.48 kg/mm front $110.36; 5.9 kg/mm rear $225.80), and I rode the bike both ways before settling on the replacements.

We next moved onto the engine, uploading fuel and ignition maps from the half-dozen Jonathan had programmed into the Power Tuner (available at www.yamaha-motor.com ). While there's nothing really wrong with the YZ's engine performance, it hits pretty hard right off the bottom. The map we settled on simply knocks the edge off that hit.

So set up, my YZ is without question the best motocross bike I've ever ridden. With its mass-centralizing "backwards" engine, it feels as though all the weight is between my calves. Turning is incredible, yet the bike is super-stable, refusing to swap even over Glen Helen's notorious braking bumps. Validating that point, I finished fifth my first time out on the Yamaha at the REM Saturday-morning races, tying my best-ever result on the Kawasaki.