Just an up-date. Opened the gearbox oil top-up thingy and sure enough oil gushed out. So it looks like 2-stroke oil had gotten in.

Pulled off the oil pump, and whatcha know, the oil seal was half way down the pump shaft. Stuck it back in with some gasket sealant and fingers crossed a week later the thing looks to be holding out.

An easy job, took about an hour. Should have taken some photos for the NSR250World workshop section. 20/20 hindsight is a wonderful thing.

Cheers for everyone’s help…..especially Andy.