Do not run the bike. In the best case it will seize again. In the worse case it will kill you. Take this very seriously.
If it's already nipped up then there will be smeared bits of aluminium on the cylinder wall. This will make it seize again. I have no doubt whatsoever about this.
Let's just say that you're flat out again, having a blast, coming up to your favourite corner and as you shut off and tip it in, the thing locks up again and spits you over the high side into an oncoming truck. Splat...you're dead!
Pull it apart and do something about it. For the sake of a couple of days off the road, and a few quid you get piece of mind to know that the engine is fresh and good to go.
If you can't be bothered then I suggest that you don't ride over 20mph and keep your fingers very close to the clutch lever.