Dating a bike

Hi Brian, good to here from you, thanks for the idea but I want to be able to use power tools as we'll.

Si, now there's an offer I can't refuse, I won't be able to put the cable in for about a month but if you would do that I'd be very happy. You can have a look at my bikes too, as long as you promise not to laugh too much
Pm'd you my mobile.

Thanks

Hello Team!

I am trying to date an obviously original ST50, frame no. 138636. By searching over here, it is obvious that Honda do not give any "hard data" about frame numbers and build year. So does anybody know any changeover points related to year of manufacture? For example, my moped has the early plastic tank, do we have any info on where it was changed? Are there any other points I should check? Thanks!

I believe the bike was built in 1970.
The plastic (bigger) tank was used in all CT70's and I believe in the '69 ST as well.

Yes the parts catalog for the Dax has this plastic tank as fitment to the early bikes.

By searching the web and forums and looking at restored bikes it seems that it is actually 1970, one 1971 I found had the sheet metal tank and helmet holder, which is absent on my bike as are its threaded holes for it on the frame.

You can't base a DOM on the fuel tank as this may have been changed to increase fuel capacity, the VIN number is the key, Honda will date it for you for a fee based on the VIN, but if the stamp is right then Waynus is most likely right.
Waynus, the plastic tank is smaller, we'll it is on mine?

angel wrote:Yes the parts catalog for the Dax has this plastic tank as fitment to the early bikes.

By searching the web and forums and looking at restored bikes it seems that it is actually 1970, one 1971 I found had the sheet metal tank and helmet holder, which is absent on my bike as are its threaded holes for it on the frame.

I have a 1970 frame and a later type, both have the threaded holes for the helmet holder, are you sure this is a Honda frame? I thought they all had the same Helmet holder?

The plastic CT70 version can hold 2,8l of fuel (2,4l metal version)

Waynus wrote:The plastic CT70 version can hold 2,8l of fuel (2,4l metal version)

Really? The metal one looks so much bigger!

Yes, no doubt it is a Honda.
It is a German spec ST50, it seems that this was the type officially imported here (Greece) in the early '70s. Maybe it has to do with it not having a helmet holder?
Here is the stripped frame:



If I need a certificate from Honda, do you have any address where I can contact them? Or can it be done via the local importers?