when i change up through the gears there is a clunk noise each time, the clutch is ajusted ok, is it a gearbox or clutch problem, i cant seem to get a smooth clutch release while changing up it pulls the revs down jerking me foward unless i rev the engine as i release the clutch while going from 3rd to forth say....
i'd bet your clutch is engaging too early, or you're just letting it out too quickly.
revving it between gears can make it an ugly thing too.
suzuki makes slick trannies generally.
Assuming there are no mechanical problems, if you're revving the enging between gear (in neutral) you should try to match the RPMs to where they will be once the gear you're going to is engaged. Since you noted that 1) you rev, 2)engage the gear, and 3) the engine "pulls" the RPMs down... sounds like you've got the RPMs too high when the gear engages. Generally, you need to rev the bike when downshifting since the smaller gear will make the engine rev faster at a given speed. Anyway, You didn't hear this from me, but if you can find the sweet spot, you don't even need to use your clutch to shift, it'll go into gear that easy. I believe this maybe be called "powershifting". But will be bad for tranny if you don't do it just right. That is, of course, assuming you don't already have any mechanical problems...
i shift without the clutch all the time. well not in town but when i'm on the highway i rarely use the clutch. release throttle, shift, hit throttle. every shift is smooth except the 1 - 2 shift. it's almost throws you off the bike when it catches gear. works best when trying to keep up with the guys i ride with ( 2 have 06 zx6r's, 1 has 06 gsxr600, and 1 has a 06 gsxr1000.)
Chain slack is the most likely culprit.
Here's how to shift smoothly using the clutch:
Just before the upshift, preload the shifter lever in the up direction. Use your index and middle finger to operate the clutch, place the other three behind the clutch lever to limit the lever travel. Now pull the lever in while holding preload and snap the throttle closed with your right hand. The shifter will snick up one. Let the clutch out quickly while opening the throttle. All of this will take a very short period of time. If you continue to lurch forward when releasing the clutch, release it more quickly and add more power.