Ok, the outer part of the bearing is pressed in & can't go anywhere i guess, but it's a roller by the looks with the inner part on the ballancer shaft--so floating in the rollers.
Don't know, but in his video it stops with a bump at about 2mm out & in, so what is stopping it.
In one vid--i think one of his--i can see a step on the ballancer shaft where the inner bearing part is sitting up to.
Not a very big step so wonder if this step comes close to the square ended rollers & rollers being trapped end on in the outer bearing shell the limiting is purely by 'said' step coming up to the rollers which likely only have running end clearance--even if say 2mm sounds a bit much in theory. I guess it can't escape.
Sounds like another Yamaha trick.
Good luck--& good management.

Here is a quick video of it. It’s not hitting the back side of the clutch basket at TDC, but if I turn the crank to a different spot, it comes out further and does hit it. I’m gonna have to tear it all the way back down and investigate

youtube.com/shorts/2_qJg1nt6rw?feature=share

Oh, gosh, yes that's a bit more--lot more--than running clearance. Good you picked up on it. Be interesting what you find.

Found a pic of the bearings. NJ3052.

NJ series roller bearings have a floating inner race (nothing holding the inner to the outer, so if both bearings are fitted in the same direction, the shaft is not constrained by the outer ring butresses and is free to move around axially.

Outer ring butress should be to the outer side of the case on both sides and tthe shaft constrained between them.

That makes a lot of sense Tinkicker!   I had no idea they used that type of roller bearing. 

It sounds like you're saying the roller bearing under the gear needs to be flipped over? 

 

My bad.  I got my NFs and NJs mixed up.  However the same applies.  If both bearings are fitted the same way, there is no constraint on the shaft.
Edit.  Also if the NJ and NF have been fitted on the same shaft by someone.  NJs and NFs are usually fitted same type on each end of the shaft.

NF has the outer ring butress.  NJ has butress on the inner ring.

They are very common shaft bearings in my line of work.

Copied a couple of pic looking from inside & outside & can see the difference. So i guess "as Tinkicker indicated, reverse the bearing [well think he meant that except we can't see yours yet] Inner part on the ballancer must be right as it is which will have the step against the ballancer. Bummer its got to come apart though--but!!.


photos.app.goo.gl/H7K5pXUnLGo9jBna6
photos.app.goo.gl/NNFcjfnJswrZRZBm6

It's been a few decades since I worked on anything with that type of bearing...  I can't remember if it was one of the Spicer or Fuller transmissions that had that type of bearing?  Maybe both. 

I'm confident you'd solved the mystery Tinkicker. 

Yep, it was the inner bearing race on the outside of the case instead of inside like it’s supposed to be. Wish that was shown in the service manual or on the parts diagrams. 

Well i'll be!!--not what i thought at all, thinking outer part. You win, but is a damn shame its got to come to bits to sort it. Learning curve for all of us if we ever need to get in there on that style of motor. Perfect video thanks.