B4 Odd frame number

[GSF89]

Recently purchased a B4 and trying to discover more info.
The frame number is 'CHMP 4081 B06MP' strange in that it does not follow the published numbers.
Engine number is MP 4647 B06MP.
Other info:
Stainless steel exhaust, looks original at least in style.
Twin front disks.
Registration documents states that it was manufactured in 1989.
Any help in identification would be welcome.

Just to add to my confusion after searching this board.
The Igniter unit P/N is 32900-10D10, and it has a green wire on the 4 pin connector in position 3 (L to R, T to B)

[ventYl]

I think that your bike is Japanese domestic market model originally sold in 1989 in Japan which was later grey-imported into country you're living in. Friend of mine was recently taking one VFR750 for a ride. This bike was declared as being sold in Japan and grey imported into Europe and similarly to yours it does not have regular frame number but odd regulatory assigned identification number which does not fit manufacturer's frame numbering scheme.

That would match the stainless steel exhaust and twin front disc. Also to my knowledge during 1989 and 1990 Bandit 400 was sold only in Japan and international sale was started beginning MY 1991 (that's why some sources state that B4 was made from 1991 to 2000 despite production began for MY 1989).

[GSF89]

Thanks ventVI,
It's more or less what I expected. This bike is in v good condition overall, I'm thinking about restoring it to original, as in 3 years it will be eligable for Vintage status in Malta.
So I'm just trying to find out the correct year for parts, and from what you say any or some of the early years should be OK.
The bike is only missing the original front end equipment (Headlamp, indicators, instruments, etc), and needs a little cosmetic work.
If any one else can shed some more light, or have contacts in Japan, It would be great to hear from you.
Thanks again to ventVI.