#4 Yamaha YFZ450
Yamaha came in as the defending champ, but unfortunately, it went out on its shield. The potent YFZ shines in actual competition--just not in ours. More pro racers ride YFZs than any other model by a wide margin. There's a good reason, too: The YFZ, when modified, is a killer, and it can be easily tailored for all kinds of aggressive riding. GNCC pro Bill Ballance used a YFZ to capture his fifth title, and Keith Little recently wrapped up the ATVA GNC TT championship aboard his Yamaha. How-ever, when it comes to everyday trail riding, the YFZ is uncomfortable and somewhat unforgiving.
The funny thing is all the changes from last year are comfort-oriented: slightly softer damping and spring rates and a better seat. They all work as advertised, but it's the overall moto orientation that hurts the Yamie in a test such as this. Stiffer sidewalls on the tires and an aggressive ergonomics package work wonders for the quad on the track but cause it to wear down a rider on a rough off-road course. Even the usually YFZ-mounted pros had some colorful descriptions for the Yamaha after their hour-long stints, none of which we can print here.
What's changed from last year: Revisions for `05 include front suspension tweaks (a new front spring rate and damping help reduce rider fatigue through increased low-speed bump absorption) and Yamaha's addressing its stiff seat (the seat now has softer, more-durable foam and a nonslip cover). The `05 YFZ also received forged-aluminum shift and brake pedals.
What broke: As with most of the machines, the Yamaha suffered from repeated flats, but the wheels held up pretty well. The rear plastic skid plate and rear brake disc also were fairly hammered early on in the event. In fact, the rear brake disc had to be pounded into a somewhat flat shape on at least two occasions, just so it wouldn't keep the rear wheels from turning.
+ Best MX platform
+ Super-strong engine
- Flat-prone tires
- Hand-numbing thumb throttle
= Great MX quad ...
| Yamaha YFZ450 |
| Retail price: | $6899; Special Edition, $7099 |
| Engine |
| Type: | Single-cylinder, four-stroke, five-valve DOHC |
| Displacement: | 439cc |
| Cooling: | Liquid-cooled with fan assist |
| Carburetion: | Keihin FCR 39mm |
| Lubrication: | Dry sump |
| Starting: | Electric |
| Drivetrain |
| Drive system: | Chain, 2x4 |
| Transmission: | 5-speed manual |
| Suspension (Type/Travel) |
| Front: | Dual A-arms, independent/9.1 in. |
| Rear: | Swingarm/10.1 in. |
| Tires |
| Front: | 21x7-10; rear: 20x10-9 |
| Brakes |
| Front: | Dual hydraulic discs; rear: hydraulic disc |
| Dimensions |
| Wheelbase: | 50.4 in. |
| Claimed dry weight: | 350 lb |
| Ground clearance: | 4.4 in. |
| Length/width/height: | 72.4/46.1/42.9 in. |
| Seat height: | 31.5 in. |
| Fuel capacity: | 2.6 gal. |
| Electrical |
| Taillight: | Yes |
| Headlight: | Dual 30-watt high/low beam |
| Instrumentation: | NA |
| Colors: | Team Yamaha blue/white, white/red; Special Edition yellow/black |