Whilst i'm getting advice, another Q:
the engine died on the track. took the cylinders off and the rear piston had kinda melted, the rings were compressed and sitting flush with the wall of the piston. Had to file away at it so i could get the piston pin out. The damage is i believe due to detonation, extreemly similar to this: http://pg.photos.yahoo.com/ph/rothmansmc18/album?.dir=f9ce. Only happened to the rear cylinder, the front was fine by comparison.
So, my question, what are the likely causes of detonation? It had BR8ECM spark plugs that are probably a bit hot for Sydney conditions, i bought it from a country town where there winters are much colder. cold days here are 15 C, there it can be lucky to get over 10 in winter. I was using a low octane fuel (91 RON), and rode it to work the day before it died in shocking traffic (10km trip=30 minutes), so it got more than a little hot.
Would using cooler plugs and higher rated fuel be likly to help solve the problem? i thinking about getting BR10ECM plugs, and using 95 octane fuel.
StephenRC45 wrote:Because it add to that "whats he doing" look at the petrol station,
First you pull up on something with no lights, sounds like a bag of nails and smells. Then for some reason measure some sort of liquid and put it in the petrol tank!? Followed by shaking the bike... after which you have to run with it to start the thing... then pulling away the same bag of nails clatting around with large amounts of revs and smoke, leaving the bloke whos filling the 4x4 up wondering wtf just happened there!
hahaha i wish, NSRs and strokers in general are as scarce as hens teeth around here. I got it at a very good price (AUS $3000, about £1200), with a full years rego and insurance, but it's a MC21R, so no bag of nails
. The dealer even delivered it 400kms to my house, as he was heading to sydney anyway! I didn't buy it as a street bike, i've got a hornet600 for that, but i do take it out every now and then, just to keep the engine cycling 
Once again guys thanks for the help, this whole DIY mechanic thing is still kinda new to me! Carburettors was about the extent of it before this!