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Should this shaft have end movement if I pull it by hand?

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McCabe-Thiele (Ted):
This afternoon I bolted the crankcase halves together, I now have the primary drive shaft in place.

I then noticed that if I pull on the gear shaft shown in the picture below  - where the clutch fits it moves out a bit is this normal - will the play be taken up when I assemble the clutch or is there something wrong with the gear shaft before I fitted it?

As much as I do not want to have to take the crankcase halves apart again it just feels suspicious.

.This shaft here where the clutch fits question by Macabe Thiele, on Flickr

Nurse Julie:
Not sure how it can move from side to side Ted 🤔 (if I'm remembering correctly.). The inside of the bearing is attached to the shaft, so there should be no movement there and the outside of the bearing should be clamped between the top and bottom cases. Where exactly is the movement?

McCabe-Thiele (Ted):
It's what you would normally call end float - grip the shaft it will pull out a little - if its out it will push back in the same amount if you get my drift. Difficult to measure I'll have a go at trying to get a figure. The bearing is solid as it's secured by the half circlips thingy. I've measured it with my caliper end part it's  around 0.75mm.

McCabe-Thiele (Ted):

--- Quote from: Macabethiele (Ted) on July 19, 2021, 06:07:23 PM ---It's what you would normally call end float - grip the shaft it will pull out a little - if its out it will push back in the same amount if you get my drift. Difficult to measure I'll have a go at trying to get a figure. The bearing is solid as it's secured by the half circlips thingy. I've measured it with my caliper end part it's  around 0.75mm.

--- End quote ---

K2-K6:
I've not as much local knowledge on the 400, but conceptually you'd not generally have a gearbox shaft "pinched" across the geabox casing to nil tolerance.  Ordinarily it'll need end float and or expansion room to avoid axial loading of the bearings at maximum heat cycle.

This one looks like it's pinched by the clutch assembly to sit tight on that main bearing to give alignment to the primary drive as priority and leave the tolerance inside the box between the visible bearing and it's opposite number on the same shaft.

The clutch is also subjecting that shaft to thrust load when clutch is operated by the lever, which would make it intolerable if it moved.

The bearing you can see is equivalent to the thrust bearing on a car crankshaft and should have virtually nil play with clutch assembly tightened.

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