am i right in thinking they will fit on with a taper roller bearing but of what size inner to match rvf stem and outer to match nc frame does this bearing have a code numbsr etc how differcult is it to do the whole job i know ive got to change the wheel spacers and axle, any help or links .

You need a fitting kit to fit them, and I happen to have one for sale. I fitted it to my bike, rode the bike 3 times then broke it for bits and will be selling the bike shortly. The complete system comprises or brand new bearings top and bottom as well as the spacer fitting kit. If you are interested just PM me.

This is what you need,