Two-strokes, 125 particularly, feel much lighter than their four-stroke counterparts, "surf" over the track more than plod across it, and accelerate with more excitement. Yes, the YZ125 is exciting. The YZ125 has a wide-for-a-125 powerband and a 6-speed transmission to keep the ratios close enough so even a novice racer has no trouble keeping it in the usable power range. Glen Helen's Saturday-racing REM track has some serious hills and the YZ accelerated my 160 pound body up them, grabbing gears (yes, higher gears!) until I shut off the throttle. In a highly un-scientific and much-enjoyed test, I told Dirt Rider test rider Mike Barrett I was going to pass him on the steep uphill and yell as I flew past. Well, I forgot to yell, but I went right by Mike who was riding one of Dirt Rider's 2012 250Fs fresh from our shootout and all dialed in perfectly.Okay, another rider may have interfered, but this goofy challenge is indicative of what happens when you jump onto a 125 - everything is suddenly flat-out brand new again, or at least a lot more fun.