I have an early 70's Yamaha 175 two stroke, bought in the UK as a fun bike stripped of lights etc owned it for twenty + years  but never known it's year, original colour and actual model. The Frame number is CT1 312347 . Can anyone help
lrb

The main list of VIN tables in the Tech Library (TL) is for US bikes. However, further down the TL menu is a tab for a schedule for some UK bikes. I have attached a link and I reckon what you are after should be in there.

UK VIN Information

Thaks very much G8uncleal, it seems pretty clear it is a 1975 model. I had hopes of registering in france where I live but that probably can't happen which is a pity as it performs very well for a 175 and is the only bike out of about 30 odd I have that actually works so far
lrb

From the UK VIN chart in the Tech Library:

1975 DT175 CT1 (Model Code 458).  VINs CT1-310101 to 400000.

I have no idea about colors or even the version compared to the US models?  Is it similar to a 1975 US DT175 (that had a complete redesign for the 1974 model year?)

Or did Yamaha have some 69-73 CT style frames and engines left over and sold them in other countries like the UK?