47. 10. That 2. 67 horsepower difference is noticeable from the saddle. Handling? KTM. A few years ago, every MXA test rider would have chosen the YZ250 to take the handling cake—no more. The Austrians have finessed the KTM’s chromoly chassis to the nth degree. The Katoom handles better than the YZ. Weight? KTM. Both the 250SX and YZ250 are very light compared to the four-strokes they race against. At 216 and 218 pounds respectively, the scale favors the orange bike. Suspension? Yamaha. The YZ250 comes with Kayaba SSS (Speed Sensitive System) suspension, and it is the best in the biz. The KTM’s WP forks and shock are light on mid-speed compression and rebound damping. Brakes? KTM. There isn’t a Japanese-made bike that can compete with the 260mm Brembo front brake on the KTM. Clutch? KTM. Yamaha’s clutch is workmanlike, but it is a weak sister when compared to KTM’s Belleville washer-equipped, hydraulically actuated Damped Diaphragm Steel (DDS) clutch. Cosmetics? KTM. It is hard to tell the 2013 KTM 250SX from its 2013 250SXF, 350SXF and 450SXF brethren—it looks modern because it is modern. On the other hand, the YZ250 plastic and design have nothing in common with the latest-generation Yamaha four-strokes. Q: CAN YOU MAKE THE 2013 YAMAHA YZ250 AS GOOD AS THE 2013 KTM 250SX? A: Yes, but be prepared to spend some late nights in the garage working on it (and some early mornings with your new paper route to pay for the updates). Here are the seven areas that we focus on. (1) Exhaust pipe. You can gain two horsepower with an FMF or Pro Circuit pipe. Although you might think that this will help close the gap between the YZ and the more powerful KTM 250SX, that is only true if the KTM rider doesn’t install an FMF or Pro Circuit pipe. ( 2) Reeds. As a rule of thumb, MXA test riders who like more midrange choose Moto Tassinari reeds, and those looking for more top end go with Boyesen. A simple mod is to remove the 5mm spacer in front of the reed block for more top-end power. ( 3) Gearing. Every MXA test rider adds one tooth to the YZ250’s rear sprocket. The goal is to gear it down to get to third gear sooner. The lower gearing makes the bike accelerate quicker. ( 4) Jetting. Although the YZ250 is finely jetted for its box-stock configuration, if you port it, raise the compression, add an aftermarket exhaust or try to skimp on fuel quality, it will ping. Play it safe and go rich–or add a touch of race gas. ( 5) Front brake. Drop-kick the stock front rotor and go oversize—260mm is nice; 270mm is better. ( 6) Clutch. We run stiffer clutch springs. Our basic setup is to install three aftermarket YZ450F clutch springs to get better bite. ( 7) Flywheel weight. Although local hotshots will tell you that flywheel weights are for enduro riders, virtually every factory Yamaha YZ250 rider ran a flywheel weight on his works bike. We run a 9-ounce Steahly weight, but Steahly makes lighter weights also. Q: WHAT DID WE HATE?
Ring: The YZ250 engine is a good solid powerplant. It lacks
the sheer horsepower of the KTM 250SX, but it’s still good.
Pucker up: Yamaha’s front brake could stand a little R&D. It
was good back in its day, but KTM, TM and Husky have better.