Topic: Serial Number/ Model Year question

[nomad]

All of the paperwork for my CB750 says it's a 1974 model.  But, according to the CB750 Shop Manual, my VIN number falls within the K3 range.  So, I'm confused.  I always thought the number after the "K" corresponded with the last number in the model year of the bike.  Is that wrong?

From the manual:

Following are the initial serial numbers of each model at the time of change...
CB750K3  Frame No. 2200001~
CB750K4  Frame No. 2341915~

My VIN (on the frame): 231xxxx (manufactured 9/73)

Is it a 1974 or a 1973 model?  Is this kind of a grey area with the CB750's or are the model and frame numbers above dead on?  Or am I looking at this wrong and I really have a 1974 K3?

[MCRider]

All of the paperwork for my CB750 says it's a 1974 model.  But, according to the CB750 Shop Manual, my VIN number falls within the K3 range.  So, I'm confused.  I always thought the number after the "K" corresponded with the last number in the model year of the bike.  Is that wrong?

From the manual:

Following are the initial serial numbers of each model at the time of change...
CB750K3  Frame No. 2200001~
CB750K4  Frame No. 2341915~

My VIN (on the frame): 231xxxx (manufactured 9/73)

Is it a 1974 or a 1973 model?  Is this kind of a grey area with the CB750's or are the model and frame numbers above dead on?  Or am I looking at this wrong and I really have a 1974 K3?

It was a convenient coincidence that the number after the K often, but not always coincided with the last digit of the year. The "K" series (serial number) rules when buying parts. The year of the title rules when registering the bike. A K3 that was never sold in 1973 could be a "holdover" and sold in 1974, ending up with a 1974 title.

Honda was sued over this situation and reconciled it with later models. But yours is in the period when these things could happen. Essentially, Honda would come out with a new "K" series whenever they wanted. It wasn't so bad with the 750s, but with the 350s and 175s, there was a time when 3 different K series wre available in one calendar year. A customer wanted the most recent year of a CB350. The dealer sold him the current year, but not the current K series. The customer sued and won, and Honda came more in line with US conventions.

[Don R]

McRider nailed it. I bought a 73 500. My brother worked there and we were assured it was the newest model. It was in fact, a 72 holdover it had the small gauges and when I needed parts 73 stuff didn't fit.

[domer]

my 500 is also the same. title says 73, neck says 9/72.

[SohRon]

I know that new car models in those days commenced production in July for release in September, so a 1973 Gremlin could be both manufactured and sold in 1972, with a production date anywhere from July to December. I believe the Motorcycle industry followed this same practice, though it may not be as simple as this with these Hondas. My '74 CB550, for instance, was built in July of '73, but there's no doubt that it's a '74 and not a '73 model...

[Hinomaru]

Nomad, If it's of any help ...

My CB750 shop manual (dated 1977) has the same exact serial number information as you posted. My Honda published CB750 parts book (dated January 1974) has the following serial numbers:



As you can see there is a conflict of data between the two references.   

I have a CB 750K with a VIN tag manufacture date of 10/73 which was made one month after yours. My frame number is: 232XXXX and it's titled as a 1974.

 

[nomad]

Thanks for digging guys!  The title says 1974 and with the reference material Himomaru just so generously provided (dated around the time the bike was actually made), I think I'll just call it a 1974 CB750 K4 and be done with it.    If I recall, I don't think there was hardly any difference between the K3 & K4 anyway.

[Shadowjack]

I'm going to make an assumption here, but probably the Federal regulations enacted for the '76 model year, such as always-on headlights and left-side shift on all bikes, also stated guidelines for titling. Gone were the days when a machine could sit on the dealer's floor for years and receive a current-year title when finally sold.

[Gaither]

Even U.S. new car dealers did this trick, at least from '46 to '48 (maybe prior) til the Gov stopped it. In some cases on model holdovers dealers could return paperwork to the factory which would send 'em new paperwork indicating the current model year. 

As an amusing result of this practice, a buddy had an antique, beartifully restored '46 Ford - originally titled as a '47. It was obviously a '46. A '47 & '48 had some different chrome and other less obvious changes but were basically the same car all 3 years. It was easy to see this Ford was actually a '46.

The title always put him in competition with the '47/'48 Fords in stead of the class a '46 was in. He had a back seat full of trophies - won almost everywhere he showed it. I enjoyed standing 10 feet away listening to the verbal battles he caused between the judges and the '47/'48 owners over the car being a '46 that should not compete with '47/48's (which had cost one of 'em a trophy). The buddy always got a big kick out of the battle and always got to keep the trophy. The date on the title always prevailed.