I bought a dtr 125 and it came without a registration on it both engine and frame numbers are still present but I can't apply for a logbook with out knowing the registration the vin the vin is 3db-000920 any help would be greatly appreciate 

No one can help you with a registration number I'm afraid, your best bet is to contact the DVLA in the UK assuming of course that's where you live (no details in your info) or the relevant department in your country of residence. Usually the VIN will tell you all about the bike like when and where it was made the model and year of manufacture, other than that your at the mercy of the government dept that deals with these things. You could contact Yamaha direct in your home country and ask them to help out with more info about the bike but they will have no data on the reg number that's strictly local stuff.

Yes I'm in uk cheers will contact local dealer see wat they say

I hope its not stolen