It's not uncommon for manufacturers to roll out new features wrapped in clever acronyms, and the 2011 KX250F is no exception; DFI and SFF are the freshly abbreviated innovations of the day. DFI stands for Digital Fuel Injection, the battery-less system aimed at taking the Kawi to the next level in terms of response and delivery. With no hot-start lever and a 43mm throttle body, the KX250F's DFI is nearly identical to the system on the KX450F, but with a different ECU setting and roughly 20 percent more fuel output required by the 250's higher rpm ceiling. A 250F revs to 13,000 rpm, and that requires a lot of fuel. The other standout acronym, SFF, represents the new, Kawasaki-exclusive Separate Function Fork consisting of Showa fork legs that handle springing and damping independently of each other. The left fork boasts one large damper and traditional clickers, while the right fork leg essentially consists of one large spring, a bit of oil for lubrication and an external preload adjuster that offers a whopping 60 clicks of height adjustment. Although unheard of on a production machine, the SFF setup is claimed to offer easier maintenance, more adjustability and easier fine-tuning, as well as promises of less weight, reduced friction and better damping.
There are several other changes to the machine-over 30 total-that make the 2011 a fully upgraded version of the almost-shootout-winning 2010 KX250F. If you want to see an extended list of revisions, check out www.dirtrider.com. Now, let's get to the fun part.
After trying fork preload in both directions, we liked the standard setting on the fork preload adjuster the best, and so long as proper shock ride height was maintained we really didn't feel a need to mess with the front end's ride height. However, it is nice and simple to tune with a wrench. The rest of the handling revisions-including a full millimeter reduction in fork offset-all help to maintain the excellent stability that we've praised the KX250F for in the past. The front end is a touch quicker and a little lighter handling than last year, and none of our testers complained about a lack of traction. The revised shock settings are right on the money, so much so that only our heaviest test rider cared to play with the clickers, and that was just to tighten up the compression a touch. In fast, repeated hits or slow, bucking bumps, the rear of the bike simply ate up whatever we could throw at it.