J&P cycle Jack shaft

[1340evo]

Hi All, ive bought a J&P cycle Jack shaft to replace mine in my 89 Evo, however it appears to work in a differant way.
The original has a solid shaft that locates in the inner and outer primary and the gear slides over it, where as the J&P one, the bit that locates in the outer primary is part of the gear and moves with it?
My thoughts are its not getting the same support as the gap between the shaft and the ID of the gear is big also.
Anyone used these or know if thet are ok?

[1340evo]

On further investigation, it looks like my part is a 89 only, with shaft number 33120-89.
The one I've bought goes from 89 to 93 and I guess must be made with this clearance between the gear and the shaft.
Anyone know if they are interchangable?.. I can't see why not?

[1340evo]

Does not say in my manual, but one I've seen online says they are interchangable, but when fitting to a early 89 to remove the scraper ring? I wonder why as everything is the same diameter? or did the seal change early 89 to the late 89 version?

Someone must of done this??