Sorry about the late suggestion, Spinner.

My bike does exactly as you describe if I hold the clutch in for a couple of seconds before trying to select first. I let the clutch out a fraction until the gears spin again, and then it's possible to engage first. Sometimes with a clunk. It's always done it, and I don't think it's anything serious.

On my bike, at times the clutch fully disengages like a dry clutch, and the gears stop spinning. I had a couple of BMWs do this, and the "fix" was the same. Just let the clutch out a bit, then pull it in and press the gearlever. It should go in, stomp-free.

Hope this is of some help.