Think that you will find that because the UK continued with the K2 model until the K6 arrived, that from around 72 to 75/6 all UK bikes would have had frame numbers in the 20******** range and as such the engine No's would have been in the 20********* for 72 but in 73 the engine No's would have changed to 22****** series in 74 23******* etc.
So you need to check what year the bike was first registered as you may well find that it has the correct engine and frame No's for a UK bike of that year.
I'm picking up on this just now, after a long absence, because I have the same thing: Frame - 208**** and engine - 231****
When I started my rebuild I used a K2 parts book, out of ignorance, but later realised I should have been using a K4 engine parts book, or should I?
Or should I use a K4 parts book for both frame
and engine?
Cheers
