Hello,

I hope anyone can help here, i have bought a YB100 that was used as a field bike and has no number plate or paperwork, how can i make it legal again. 

If the previous owner can't tell you anything, I'd be asking them why not - a usual reason is that the bike was stolen at some point, so you may well have bought a stolen bike that would never be yours legally on the road. Finding out the bikes history could mean you end up losing the bike (at the extreme).

if you can see the frame number and engine number, perhaps you could get help from the DVLA. Or given the age of the bike and the potential lack of history, maybe joining the Vintage Japanese Motorcycle Club could be an idea. I think they can give you a document based on your frame number which can confirm the manufacture year of your bike which will help you get a proper age-related registration number for it. Either way, I'm sure the VJMC will be able to advise.