Throughout the test, my main focus was to tame the power and make the bike a little more friendly through the throttle. The biggest step was from the Vortex ignition and its 10 maps. A final gearing change to a 48-tooth rear sprocket made for longer pull in each gear, but as I mellowed the power more, the gear gaps grew wider and tougher to pull. The worst part of running the 48-tooth sprocket was that second-gear starts could be brutal on the clutch, and the same with pulling third gear in tight turns (which the bike would do). Riders not familiar with my setup had an easy time getting the clutch hot, but it held up to the abuse well, even the basket and clutch fingers.
My suspension setup from Pro Circuit was also a huge reward. In conjunction with the PC link pullarm, it seems every bit as good as the phenomenal 2007 KX-F, only giving up a little in the plush department but being more stable all the time. Putting on the Flexxbar only made it better, especially when we set it up with a little "rebound" damping by placing shortened elastomers on the outer side of its mounting bolt. Upgrading the levers and keeping them and the cables lubed has gone a long way in retaining the fresh feeling.
So did the KX-F have any of those first-year blues? Not for me. It has held up commendably, and through my tuning, it even works better for me than the '07 KX-F. Yet after riding it, I'd change only a few things on this trusty '06. First, I feel there is a better gearing solution for the four-speed gearbox, possibly ratios a little tighter than my current 14/48. Second, I'm betting Pro Circuit has some better valving for the suspenders after a year of testing; it is way past time for a rebuild, especially the shock. But the best thing about this KX-F and most of the aluminum-framed bikes I've put a lot of time on lately is that as a whole they still feel pretty fresh after a hard year. And after putting 10 more hours on it since the top-end job, the bike is as strong and tight as it was when it was new.
Running TallyHours on Bike: 48Modifications: $3042.40 (none since last update)Maintenance and Repairs: $691.97 (not including tires)2 oil changes and 1 filterOil filter: $6Silkolene Pro 4 10W-40: $13.99 per literPiston: $95.76Piston pin: $18.94Rings: $32Circlips: $0.30Base gasket: $8.52Head gasket: $25.84Dunlop tires 756RR, front, $107.13; rear, $127.22