Update -

Bike did not seize. After taking off the gear box cover and disassembling everything, I turned the motor over by hand with no problems. I then put the gear back into place and the kick start worked again. Bolted everything back up, got the bike started and rode it for 5 or 10 min.

Then - Same Problem!

Bike began to drop revs, stalled, and the kickstart froze in place.

Clearly there is a problem with either the flywheel, the gears, or the crankshaft sprocket getting stuck.

Anyone been in this "bind" before? Any suggestions? I'm stumped. I couldn't find anything strange in the gear box - although I should say I have never seen an NSR gearbox before either.

Thanks

Adam