So the whole reason I haven't been out riding around on my Honda 250 is because the starter clutch has been broken all this time. I took it apart when I was younger but there is no way to repair the unit and finding a new one is not easy. I have a spare Benly 150 engine so I took it apart to see if I could use the starter clutch from it. I took off the magneto and the starter clutch looks like new BUT the holes are in a different arrangement around the clutch unit, bummer. Here are some pics comparing the two.
First here is the broken starter clutch from the CB72
As you can see there is a good crack from one of the roller cavities. The metal case surrounding the part is destroyed as well. A couple springs went flying and the pins that push the rollers are also damaged.
Here is a shot of the Honda Benly 150 starter clutch. It looks the same but the holes are machined slightly off from the arrangement on the 250 unit.
Here is the starter clutch on the magneto. The face of the starter clutch faces inward when it is assembled onto the crankshaft.