Hi all,

As a matter of personal interest, how many different versions of the CB 400 'Super Four' have been produced over the years, and what are the major differences between them?

After all the digging I can do, I've established that:
- NC31 is the 'Spec 1' (ie non-VTEC) version of this bike.
- NC39 is the 'Spec 2' (VTEC) version.

Is this correct? Are there any other versions? And VTEC aside, what other major differences, if any, are there?

There has been quite some model development since the introduction of the CB-1 in 1989
I have a related CB400 Four NC36 1998. Similar engine as the Super Four but more bling on the bike.
Honda have a timeline for their motorbikes on their website

Hey Mansie, great stuff. :)
The disadvantage with greys is that the English-speaking world tends to be more-or-less totally reliant on technical info coming from forums like these... not a bad thing, since there is no substitute for people actually owning and working on the bikes in question on a daily basis.
But if only more of us understood Nippon (and had the PC apps to go with the language), the Japanese sites would literally be gold mines of info for us, too.

That's the thing with the Japs... I worked for a time at Toyota SA's technical department, and you notice that they are highly community-centred. No one in trouble gets left in the lurch - it simply isn't done. And if they suspect there's a bona-fide technical issue that needs sorting, they fall on it like rabid wolves!

By the way, does anyone know how to determine Super Four year-model by VIN number?

On the issue of help: I had searched the web everywhere and contacted a few Japanese guys who owned the same bike as I did. Often they are not confident about their English. One guy in particular did help me a lot, ordered a few parts that he got delivered. After he crashed his bike he had no need for the manual any more so he posted it to me. Ace guy.
The CB400 is incredibly popular in Asia. I met a group of owners in Singapore. They are also on the Singapore Bike Forums. I don't know how useful it could be for you to sign up there.
Cheers, Mansie