Many folks have touched on the proper technique for high performance shifting. I wonder how many of them realize what or why it works so well. As a street rider that wants a long riding career, I'm always looking to improve, and part of that involves participation in ERC courses, and soon the Lee Parks Total Control Riding Clinic in Phoenix. In preparation for that event, I have read Lee Parks' book Total Control High Performance Street Riding Techniques. It is NOT about racing, but rather, how some racing techniques will make you a better steet rider. He devotes an entire chapter to shifting, allow me to share with you how, why, and when to use the clutch.
"The basic upshifting technique involves preloading the shift lever with your foot with slightly less force than that needed to engage the next gear. Next, quickly roll off the throttle approximately 25% of its twisting range. When this happens, the torque force on the tranmission will temporarily unload, and the preloaded shift lever will now snick inth the next gear. For regular shifts at less than full throttle, a simultaneous light stab of the clutch will help ease this process. For full throttle "speed shifting," no clutch is necessary. In fact, it's actually harder on the transmission to use the clutch in this type of situation than to just let the loading forces do the job. Most riders are amazed the first time they find that they don't need to use the clutch in high-performance shifting. These techniques will make the ride noticeably smoother for passengers as well." He goes on to talk about high-performance downshifting. Suffice it to say it's more difficult and requires lots more practice.
For the past month or so I have been using this technique religiously on the FJR. As most of my shifts are at less than full throttle, I use a light stab of the clutch, but even at less than full throttle and higher rpms, I've shifted smoothly without clutch by the simple preloading of the lever and unloading the tranny. Lee was right, you won't believe how easy and smooth this makes the ride.
FWIW, this same technique is taught in the open wheel racing car schools like Derek Daley and Skip Barber that I have participated in. While these vehicles don't have a sequential gear box like the FJR, they don't have syncro's either, which is why the technique is used.