Thanks for the replies - I'll have a look on the parts manual. The code listed above appears on allen performance website.

I've got an RGV with NS400 engine, with TA21 NSR250 carbs. I've just fitted 500cc barrels and want to rejet. It's got 190 at the front cylinders and 192 at the rear at the moment, it's too rich with either open carbs or individual ramair pod type filters.

I really need to take it to a dyno place and get it set up properly.

Cheers, Mat.