Inherited a crusty ratchet top. I have one for my current build so this one is going to be a rebuild candidate for me to learn on. Any help dating it? Is it as simple as the 65 shown? It's also stamped N-18 on the inside of the ratchet lid.

 

The -65 is the casting part number, used for years. The anti-theft number does help, but IDK how to decode it.

 

I guess the best thing to do is to read up on the differences between the years and figure it that way.

 

Casting number 34703 65 was used for 1965 models through mid-1977 models.
I don’t know what 2E indicates and my best guess is that it may be an inspector marking. Some other cases have E2, E1, 1E, 1, 2 or E.

The ID on the front of the case is intriguing, partly because the 9, even though it is a round-back type, doesn’t look exactly the same as other examples in my photo collection. And the 3s have a flat top when l would have expected a round top. Also notice the 3s don’t line up exactly with the other characters and that is interesting because most (not all) of my examples of this form of ID look like they may have been done with one strike, suggesting that all characters were contained in the one stamp-holder.

I can’t see any sign that the area has been altered but what does that area look like to you? Is there any sign of alteration? If not then maybe the case is a replacement and someone used the ID from a damaged case? Or maybe the ID was applied at the factory but wasn’t done with the usual types of stamps?
Apart from being called an anti-theft number, it’s also known as an additional original component identifying number or a security code. When stamped at the factory, the letter E was used on Big Twin trans cases for some 1966–69 models but other letters were also used for 1966–67 and 1969. And maybe for 1968?

Inside the lid and partly hidden by the fluid may be casting number 34809-52 which I imagine first appeared for 1952 models. Following that may be a circle E which may indicate Eck Industries. After the circle E it looks like EQ2 and I've seen that marking before but I don’t know what those three characters represent. Next may be a lone 4 while some other lids have a lone 1, 2 or 3 in one position or another.

Provision for a switch on the lid first appeared as of 1959 models and your switch may be the type introduced then but obviously I don’t know if that switch is original to that lid.
Another clue may be in the screw holes because as of 1965 model lids the screws changed to socket-heads and the countersinking appears different. Also changing to socket-heads as of 1965 models were the screws in the shifter shaft lever and shifter cover.

Some lids of that type have date codes such as 12-74, 1-75, 8/75 and 8/14/78 but I don’t see a date code on your lid. But the lack of a date code doesn’t necessarily mean anything because I’ve seen other lids of that style without them.
I don’t know what N 18 indicates. Other lids of that type have similar markings such as D3, N3, N6, N9, N12, N28 or N30.

I haven’t studied shifter cams much but yours may be one of the types used for 73/74 or later?
Eric

 

Excellent info. I hope to dig into it more this weekend as I'm planning a full rebuild. I'll provide more info when I have it. For what it's worth, I have a '71 FX ratchet top on the bench right next to it and from the brief comparisons, they look to be the same. I got this tranny in a parts pile from my late brother in law. He had a '59 pan chop and some of those OEM parts were in the pile. I was thinking it was from that bike at first but I doubt it.

 

Finally was able to tear it completely down. Code under lid suggests it's a 50's?

 

Well a couple things, it's got the later 2-1 speedo drive so the guts are post 69. Can't remember where I found the dating codes but they were on an old iron bike site, like chop cult or similar, dated a bunch of stuff before my sale last year.

Clean it up pull the bottom studs, heat it up some doesn't take much 150-180f or so to see if there are any cracks or fracturing going on you didn't see, micro cracks pop out very visually on aluminum casting doing this. Soak it in acetone, maybe heat it once more to double check, any inclusion pockets or micro cracks will show now. All good, sealing loctite the studs in place and coat the inside with Gylptal. Those old castings were porous to a fault, they'll sweat oil.

 

As I mentioned in my previous post, I imagine casting number 34809-52 first appeared for 1952 models. Provision for a switch first appeared as of 1959 models and your switch may be the type introduced then but obviously I don’t know if that switch is original to that lid. Another clue may be in the screw holes because as of 1965 model lids the screws changed to socket-heads and the countersinking appears different. Also changing to socket-heads as of 1965 models were the screws in the shifter shaft lever and shifter cover.
Eric