Thanks mate,
I live in QLD Australia and the nearest mechanic with a clue is in Melbourne (2000km away!) so all help is much appreciated. He suggested that the crank centre bearing seal may be shot . If it is I can't afford to fix this as parts availability is poor and expensive. Rings and gaskets are available however, so being an ex engine fitter I'd be happy to replace the rings. Just one question(s): How much compression should it produce throttle fully open , kicked over till I expire? I am running Mobil Semi-Syn 2 Stroke oil and Castrol 4T in the gearbox are these OK!. Have had many bikes over the years 91 VFR, 98 VFR , 02 VFR, TRX 850 and currently commuting on a CB 1300 as well as owned a few I don't want to mention! but the NSR handles, stops and goes better than just about anything I've ridden. I'm absolutely addicted to tinkering, checking and improving it. Have a good day one and all and ride safe. P.S I believe the engine has only done 22000 km, should it need more than rings?