If you read our review of Yamaha’s incredible YZ250F, you know how excited we are about that bike. Yamaha has just introduced the off-road version, called the WR250F. We’ve had the bike a few days, and this is part one of our ride review.
To begin with, you need to know that we are testing a U.S. version of the bike. In the U.S., the stock bike comes with a very restrictive exhaust, a very small air box opening, and a throttle stop that prevents application of the last one-third of the throttle. Like many riders will do, we immediately modified these three items before extensive testing. Here is what we did.
You can open up the air box slightly by removing the snorkel, but we removed the entire top of the air box (four screws). You will have to clean your air filter more often, but the WR will breathe much better.
Next, we removed the baffle from the muffler. There is a single screw holding in the baffle, and this takes about one minute.
We then removed the throttle stop, which is a pin on the right side of the carburetor (behind the black cover). Remove the pin (it is difficult, as it has plenty of Lock Tite on it), and then shorten the shaft of the pin by approximately sixty percent. The shaft is the length of the pin before the threads. We used a hack saw, and then smoothed the end of the shortened shaft with a file. Then re-insert and tighten down what remains of the throttle stop.
Finally, we have been experimenting with re-jetting the WR now that it breathes so much better. The stock main jet on our bike was a 170. We are now running a 185 main, and we have turned the fuel screw one-half turn out (for a total of three turns out). Leave the needle in the stock position (third groove from the top).
With these modifications, our WR runs even better than the YZ250F we tested a couple of months ago (we didn’t have time to play with the jetting on that bike). The bike has an extremely broad powerband, with good low end, a strong mid range and a very strong top end pull. With the jetting dialed in, it is hard to believe that this is a 250 four-stroke.
For all around riding, we definitely prefer the WR transmission over the YZ transmission. All things being equal, this is reason enough to buy the WR over the YZ. The WR also has a smoother powerband, with less radical cams and a heavier flywheel.
The WR is sensitive to jetting, and it took us a while to settle on the correct jetting for the better breathing bike. We are in California near sea level, and the air temperature is relatively warm for this time of year (in the 70s). We may refine the jetting further and report back during part two of this review.
The suspension on the WR is outstanding. The handling is also excellent, but, at this point, I would be tempted to buy the YZ fuel tank and seat and put it on the WR. The three gallon gas tank, coupled with the shape of the seat, prevents you from getting very far forward on the bike for turns.
After we put more time on this bike, we will report back with more details and our lasting impressions.