Hello,
Well after all this time you would think i had managed to secure a registration number for my DT175!!
No such luck! I have twice applied and twice had the letter of rejection from DVLA stating i needed to add something i had not done earlier. This last letter arrived yesterday and now says even though i have a letter of authentication proving when it was built, i now have to supply a NOVA certificate. I have gone onto the HMRC web site and now am completely lost due to only being able to certify a vehicle imported from an EU country not anywhere else!!
Please would anybody tell me how i apply for a NOVA on an old bike which i have NO knowledge of where it originally came from?? I bought said bike in good faith thru' ebay and have it running a treat for daytime use only, but i cant use it on the road, which is not helpful when you live in a town!!
Any help would be better than where i am now 

Does it have any remnants of a headstock decal?  Could it have been a US model?  VIN?

If you send the VIN to DEET, he might be able to make you a replacement decal which includes the production date if your model was sold in the USA.  For a DT175 it would have to be 1981 or older. 

Other than that, maybe you can contact Yamaha?  Yamaha USA has helped others...  not sure about Yamaha UK.

MarkT
Thank you but the frame only has the numbers in the steel punched in, no decal tag that used to be pop riveted on. The bike had been powder coated before i bought it so had no remnants of the old decal with it. I assume DEET is a contributer to the site and if i send him my numbers he might help??

Yamaha didn't rivet a tag...  it was a decal that would be removed/destroyed by powdercoating.

What is the prefix of your VIN?  First three characters or so.

DEET can be contacted by email here: yamaha(at)nc.rr.com  Replace (at) with @

NOVA is a UK requirement, to prove that VAT has been paid on an imported bike.

I can't say that I've done any investigations on this matter, but if you picked the bike up cheap, then it might be easier to pay the VAT (might only be 5%) and get a NOVA that way. Or maybe go back to the seller and ask if they have it.