EFI couplers. Put your fancy new hat on and use the owner’s manual to locate the stock coupler (on the left side of the bike tucked in behind the radiator and shroud). Pull the rubber coupler guard from its mount, remove the guard, unclip the stock EFI coupler and install the optional white coupler. All you have to do is plug it in. The white coupler, also known as the lean or aggressive coupler, decreases fuel delivery by 4 percent. It is a noticeable change, all the more evident on a track where the dirt is disced deep. We would like to point out that of all the 250 four-strokes that come with pre-tuned EFI adjustments, the RM-Z250’s couplers are the most noticeable. That says a lot. Every test rider preferred the lean coupler. Throttle response was improved, and the somewhat flat feel of the powerband was livened up considerably. The kicker? The 2013 bike with the lean coupler was superior to last year’s RM-Z250. The rich coupler (gray in color) was our least favorite option and only worked moderately well on rock-hard tracks or in the hands of beginners. Q: HOW DOES THE 2013 SUZUKI RM-Z250 RUN ON THE DYNO? A: Both the 2012 and 2013 engines are essentially the same from 6000 rpm to 8000 rpm, then the 2013 RM-Z250 loses almost a horsepower from 8100 rpm until 12,000 rpm. At that point on the dyno, both engines intersect and the race to the top begins. At 12,500 rpm, the 2013 RM-Z250 is still holding strong while the 2012 bike falls off significantly. The 2013 RM-Z250 makes 38.01 horsepower (the 2012 model made 38. 12) with maximum torque at 19. 29 foot-pounds (compared to 19. 85 foot- pounds last year). Obviously, the 2013 RM-Z250 makes less power than the 2012 model, but the numbers are moot on the track. Compared to all the other 2013 bikes, the RM-Z250 falls fourth in line (behind the KTM 250SXF, Kawasaki KX250F and Honda CRF250). Compared to the KTM and Kawasaki, the Suzuki’s dyno numbers are weak. Still, the Suzuki is the best of the rest in terms of a strong and consistent dyno curve. Q: WHAT IS THE GREATEST ATTRIBUTE OF THE 2013 SUZUKI RM-Z250? A: Any Suzuki RM-Z250 owner would give a glowing review of the bike’s handling tendencies. The RM-Z250 has no equal when it comes to cornering. It can hit inside lines with very little rider input, but also blast around sweeping turns with relative stability. Thanks to stiffer fork legs and decreased flex, more advanced riders can push the limits of the bike’s capabilities in transition from braking to corner entrance. The only downside to the RM-Z250’s geometry is the possibility of headshake. The 2013 setup is the most stable RM-Z250 since Suzuki developed their own chassis (after the messy Kawasaki-Suzuki alliance of 2004); however, the front end still trembles like a teenager on an energy-drink binge down fast straights where the front end is loaded. The best solution is to drop the forks down in the triple clamps, tighten the steering stem nut and make sure that there is a proper amount of race sag. Even so, every MXA test rider was willing to trade some straight-line stability for the RM-Z’s precise cornering ability.
The in-crowd: Suzuki joined the Showa Separate Function fork
fray. As a result the RM-Z250 suspension is improved.
Plug in: The RM-Z250 comes with three EFI couplers to
change the mapping. We preferred the aggressive setting.