RichG wrote:sorry guys, poor choice of words using 'minor'. well corrected.

Sorry Rich, I didn`t mean to sound like the strict school teacher!

NSR_hongkong, When you stripped the top end, did you remove the gearbox? If so, it could be that there is a circlip or thrust washer missing?

Is the gear lever action stiff? It is easy to get the selector drum spring trapped between the circular cassette gearbox mounting plate and the crankcase. This makes the gearbox hard to shift.

Check out the workshop section to adjust the carbs. Just set the floats to standard. 13mm from gasket face to bottom of float when the float tab is lightly seated against the valve if I remember correctly?
It sounds like you have flooded the engine or set the float level too high. Assuming you haven`t changed anything else?