1. At a recent open track-riding day we attended, we were stunned to see the amount of riders who were wasting a lot of time and physical effort using the clutch to upshift. The continuous rise and gradual fall of the engine's rpm between each shift as bikes roared by us in the pits had us wondering if there was an epidemic of slipping clutch plates that we didn't know about. While it may be an important ritual for beginner or novice riders, using the clutch for upshifts during aggressive canyon or track riding is totally unnecessary (unless, of course, your bike has some shifting/transmission issues that prevent using this technique). In fact, there are many riding situations where it can be a nuisance and even a hindrance to quicker and smoother riding.
2. A motorcycle's gearbox differs from your typical automobile transmission in that it can actually change gears under a small load, and only needs a slight interruption in the flow of power to accomplish an upshift. Its constant-mesh, sequential dog-engagement design means it can change gears much more readily than a typical automobile synchromesh transmission that requires an almost total stop in power flow, which is why using the clutch is necessary for upshifts in manual-transmission cars. This is why "power shifters" are so popular with motorcycle racers; by using a device that cuts ignition power momentarily while upshifting, the rider is able to keep the throttle pinned wide open, saving time and effort.
3. Basically, the technique is simple: Instead of shutting off the throttle completely and pulling in the clutch while you shift, just let off the throttle a small amount and perform the upshift in a quick, near-simultaneous movement; ignore the clutch. Don't shut the throttle off completely, just let off enough to get the shift done. Upshifting without the clutch also gets you in the habit of performing the shift quickly and smoothly, as otherwise the weight transfer from letting off the throttle can upset the bike's handling. Once you become accustomed to using this technique, you'll be amazed at the time and energy saved (and you'll probably reduce wear and tear on your clutch plates, too, judging by the clutch slip we could hear as riders at that track day tried to squeeze and release the clutch lever quick enough during each shift).
4. There are many riding situations where the physical exertion saved from not having to constantly squeeze the clutch lever during upshifts can be a huge benefit. For instance, when accelerating through a set of tight switchback turns or chicanes, your arms and hands are busy with the effort of steering the bike, and your body positioning may also prohibit being able to release your grip on the left bar to work the clutch lever. In scenarios like this, there simply isn't the time or the wherewithal to deal with the clutch, and at the end of a long ride or track session every little bit of your energy level conserved can help you avoid making a crucial mistake. Also, the smooth riding that results from learning to shift properly will pay major dividends in added speed on the road or track.-SR