The Unofficial CB450 Page
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450 Model

Picture of 450 Motor

KO 1965-67
K1 EARLY 1968-LATE 69
K2  LATE 69-70
K3 1970
K4 1971
K5 1972
K6 1973
K7 1974

I've seen so many wrong dates on bikes.  Of course many things can cause this.  Including bikes sitting unsold into the next year.  Bikes being re-registered and the like.

K1 Model Info

The K1 has 7 variations so its easy to mistake the model.
There were actually 2 CB450K1's or at least variations which could be classed as 2 separate models. The 1969 is quite different in many
respects.  The blue one is as i found was chromed up a bit in the 70s
and has the 1970 front end which of course were compatible with the cb750.

About 6000 early K1's were made with the small triangular sidecover badge which simply had 450 on it in black.  The triangle below it was in red, the badge was a double layer brass and chromed.  What distinguishes the early K1 is this badge and the 2 horizontal pressed lines above and below the badge the full width of the sidecover.  Also the seat is peculiar to this early version, it is quite flat and has course vinyl covering the top pad (to prevent slipping i guess).  The sides are smooth vinyl, and the piping bordering the two vinyls is white.

Transitional models recieved a thicker padding and pleated top cover.  the sidecovers recieved the new version badge with 450 DOHC and a smooth surfaced sidecover.

The american market models had slimline fenders whereas ours and europe got the deep valanced fenders.

K3 Model info:

In 1971 the CB450 came out with the CB500/4 front end (fork legs,front guard,brakes and front wheel.)

Misc Model info:
The Honda company continuously strived for a high degree of quality control and new parts were continuously introduced to curb any fault or any chance of a fault.  Honda sent to dealers service sheets all the time.  I have many here in the front of partlists. 
part no---description---number required--reason for change---new part number

You have to admire Soichiro Honda for his quest to provide the best product for the best possible price, and his ability to be able to stand by his word to provide any part for any Honda he produced.  Things have changed since his death, now youre lucky to get parts 20 years old, its just not good economics from a new sales point of view.

Information provided by Graeme Duckett.


The following information was found on the net, and looks like it may have been an aftermarket manufacturers application sheet.  HOWEVER, I have doubts to it's accuracy regarding the model year, frame #, and engine #

MODEL YEAR/S TYPE Gasket kit A Gasket kit B Engine No. Frame No.
CB450 K0 1966 A 06110-283-T20 06111-283-000 CB450E-1000001 CB450-1000001
CB450 K1

06110-319-S01 06111-319-S00 CB450E-3000001 CB450-3000001 to 3008955
CB450 K2 1970 - 71
06110-319-S01 06111-319-S00 CB450E-3000001 CB450-3008956 to ..
CB450 K3 1971 A 06110-319-S01 06111-319-S00 CB450E-4000001 CB450-4000001 to ..
CB450 K4 1972
06110-319-S01 06111-319-S00 CB450E-4100001 CB450-4100001 to ..
CB450 K5 1973 U 06110-319-S01 06111-319-S00 CB450E-5000001 to 5046895 CB450-5013282 to ..
CB450 K6
A 06110-319-S01 06111-319-S00 CB450E-6000001 to 6026022 CB450-6000001 to 6025991
CB450 K7
A 06110-319-S01 06111-319-S00 CB450E-7000001 to 6022907 CB450-7000001 to 7022920
CB450P ? D 06110-283-T20 06111-283-000 CB450E-1000001 CB450P-1000001