C72 from France

[sky.fred]

EUREKA
I think I've got it.
The selection mechanisms of the CA72/77 -for the USA- and the C72/77 were different and I believe that the “C” Japanese had an N1234 selection but I'd like to have confirmation

The drums were different, but so were the forks.
On my C72, I have a 24301-259-000 drum and 24211-259-000 forks.
So I need forks 24211 268 000 to fit drum 24301-268-000 and get 1N234 gears.
You can see below the difference between the two types of forks, in the position of the pin shift fork

24211-259-000


24211 268 000

[sky.fred]

I could only find this one photo of the selector on my C77, it’s probably not a lot of help.

My motor is dismantled and after checking, everything seems to be in accordance with the parts list and the assembly is correct, but it's a fact that when I'm driving, the gears are “reversed” and there's no stop in 4. Given the drum xxxxx259xxx with a single groove that goes all the way round, technically it doesn't seem possible to me that the gearbox could operate other than by returning to neutral after 4 .... or else there's something I really don't understand .... but no matter how hard I look, I haven't found the slightest possibility of a stop in 4.
I've come to the hypothesis that Japanese C72s, or at least some of them, had this type of selection, because after opening the engine, I'm not sure if it had already been opened, but only a Japanese person could confirm this.
This is a possibility, since Honda seems to have hesitated between “English” and “German” gears on its early models. The rear brake lever with the drum on the left and the chain on the right also seems to show that Honda could have originally put the selector on the left, otherwise why make it so complicated?

Reference xxxxx268xxx fits CL, CB or CA72/77. This is the version with slots, two grooves and 3 selection pins, whereas the xxxxx259xxx version is round with a groove that goes all the way round and 5 selection pins.


The 259


The 268

[sky.fred]

While we're waiting to find forks that are in good condition and not outrageously expensive, we might as well keep checking the engine.
Opening the engine allows me to see that it's in good condition and that there's very little carbon build-up, but there's also a surprise..... I've got 4-ring pistons, and the scraper is under the pin. I don't know which models had these pistons, but certainly not the latest evolutions, which seems to correspond with my “inverted” gearbox.
I need to change the roller chain, which is damaged, and for safety's sake I'm going to fit a new timing chain.

[Michael Stoic]

Sky Fred:

Vague recollection of some unusual shifting patterns on obscure (in the US) early models. This is very tenuous, but was discussed on the old VJMC mailing list - decades ago, by now.

Bill Silver may be the best informed about this. I would definitely keep the bike original for the time being.

You are a talented mechanic and could do the mod to another shift pattern later, between lunch and dinner.

--
Michael

[sky.fred]

With vintage motoguzzis, I only order parts once they've been dismantled, because in the 70s and 80s, Italians used to fit their bikes with the parts they had on hand, and not always those listed in the parts list. But with Honda, I'm surprised to find parts that come out of nowhere.
I'm not a “museum” collector and my bikes are often ridden and sometimes far away, so I give priority to reliability and ease of use, but I don't make anything that isn't reversible, so I'll carefully store the “surprising” original parts.

[Michael Stoic]

I don't make anything that isn't reversible, so I'll carefully store the “surprising” original parts.

A sensible approach!

[sky.fred]

While we wait for the rest (my various parts should arrive within the week), a test of the C72 in the 1962 issue of Moto-revue.
It's in French .... Your turn to use a translator.