10-11k on the rev counter is right. twostrokes don't rev to the moon like fours. as for the rear wheel.
i cannot think how you would get a nsr500 rim in the swinging arm. the 16 is very narrow. i,m in the process of fitting an MC18 arm to mine ,so i can run a 150 tyre! you need to ask the last owner whats been done to the bike. are the carbs standard? or MC18,21 carbs. as for pod filters. andy runs pods on his 21 ok,and i am thinking of useing them when i fit my MC18 carbs 
stephen RC45 thinks they should jet ok on his dyno.
bring the bike along to the track or dyno days i,d love to get a look at that back wheel
