Thanks MarkT! An incorrect flywheel was my first assumption too, and I bought another supposed CT1 Flywheel on ebay. The replacement flywheel has all the same measurements as the first one and fits in the same way. It does seem possible that I ended up with 2 of the same wrong flywheel form another similar bike.

Here are some measurements for the flywheels that I have.
OD: Approx 120mm
ID: Approx 85mm
Depth of cam lobe from top of taper collar: Approx 20mm

I'll attach some images of the measured flywheel. Sorry for the inch calipers - I don't have any in metric.
Both flywheels that I have are marked Hitachi F-130

Wow the plot thickens. CT2 & CT3 had smaller OD flywheels. People advertise everything often as CT1 because CT1 numbers still go to the end of 1973 CT3 & prefix is still called CT1. Now i don't suppose you got a CT3 flywheel. In saying that i wouldn't have thought the cam would be any different. But as i understand it 'now' the cam doesn't sit deep enough which is a whole new ball game. CT1 flywheel is noticeably heavier than the 2 & 3. In saying 'that' i'm not sure if they're Hitachi all the way to "73 or something else like ND. MarkT would know. Might get to my AT1 & read the number off the flywheel. ---& measure diameter.

A real mystery indeed!

The flywheel weights 1.3 kg if that means anything to anyone.....

Yes my flywheel on my "70 AT1 is an F130 Hitachi. Trying to get as near as i can lining the metric verniers up through the cover it looks 116mm but might be a fraction out--same flywheel anyway.

Here's another rough looking CT1 plate to compare pics but don't know if it helps. Almost like someone has fitted a left crank half with a longer shaft. But that aint gonna happen & looks ok for length in the pics if it's yours i'm looking at.

Okay, found 2 CT1 F130 Hitachi ignitions... both the same.

Some pictures:

Stator


Inside of flywheel:


Flywheel on stator from back side. Note that the points cam is almost flush with the stator plate.


I measured a little differently... ~31mm from flange surface to top of points cam.

I have some more pictures but I think I understand the misunderstanding...

The points cam is a VERY subtle "bump" in the approximate area in the pic below.


The actual points cam is the area marked by the arrows, not the area marked with the X in the picture below.

Some other measurements... the ID of the tapered hole is about 19.5mm inside the flywheel and 14.2mm outside the flywheel.

The depth of the flywheel is about 37mm:


The points cam starts about 3mm or 4mm below flush from the rim of the flywheel


Hope this info helps!

Well MarkT, you are officially the man! I was looking at the flywheel all wrong. Looking from the top, I was convinced that the little lip below the points cam was the cam. Total optical illusion I guess. Turns out the only wrong part was me.... I set the points, and I got a fat blue spark.

I can't thank you guys enough. Feeling like and idiot over here, but you just saved me from an endless goose chase.

I'll sleep tonight lol--already past midnight. Top Marks to MarkT.