1982 kz440 starter problems

First time posting so here goes. Just purchased a 1982 kz440. Pulled the dead starter out when I got it home. Prev owner had most of the work down before I got to it I just pulled the bolts out and slide it out. Rebuilt it starter works great. Problem is I can't get the starter gear onto the starter. Either the splines are wrong or shaft is to big. I guess my question is are these starters interchangeable with other machines? It fits and bolts in perfect other than the gear not fitting. Could this be a starter for a different bike the guy just crammed in before I bought it?

Sorry for the long post. Thanks for any help.

Quite a few small and medium displacement Japanese motorcycles use a chain drive starter. It is certainly possible to have the wrong starter or the wrong sprocket or both.

Can you see a part number or other identifier on either part?

The numbers on the starter are mitsuba sm-8208 I think. The last number has a gouge in it so its hard to read. Judging by other parts of the bike I wouldn't be surprised if it was wrong. Any suggestion on were I might find a correct starter.

The gear for the starter is a very precise fit onto the splines on the end of the starter. It might just be slightly misaligned. Double-check that the gear fits onto the end of the starter without the chain wrapped around it, as the chain might be tweaking it to one side or the other and causing problems.

I've tried to put it on with and without the chain. Every thing short the hydraulic press to put it on but it shouldn't be press fit. The shaft on the starter just seems to big or the gear is to small.

Is this the gear that came off of the starter originally? If it slid off originally, it will slide back on with the correct orientation. Try rotating the gear as you line it up to try and get the splines to line up.

From your pictures, everything looks to be original so you shouldn't have issues. That definitely looks like the correct starter, as it has the positive terminal in the correct orientation and has the tapped holes for the starter cover bolts moulded into the end caps.

I don't know if this was on the starter or not. It was the gear sitting in the bottom of the stator cover when I finally drilled all the screws out the prev owner stripped. I thought it would just slide back on to but its to small for the shaft on the starter. So I'm going to try a couple local salvage yards and see if I can't get a replacement starter and gear or one or then other that will work. Didn't want to spend that much but id like to get this back on the road.

Typically, they should slide off and on easily. I dont think there is an index.

That's how I thought it should work. And the splines aren't damaged on either part they just don't fit together. So I'm guessing the prev owner swapped some wrong parts around. So I'm headed to the salvage yard in the next few days hoping to find what I need to get this bike going.

In the next day or so, if I remember, I'll try to count and measure the splines on a Kz400 (It's my buddys' son's bike). Maybe you have some mix of 400 parts on the 440.

1975 Kz400D2 starter shaft and sprocket.
The starter shaft OD is about 13.5mm.
There are 31 splines.
The sprocket has 13 teeth.