Stem & hub bearing install issues.

When installing the steering stem and subsequently wheel hub bearings, I've found that the bearings will bottom out on the center spacers before the outer races reach the frame/hub lip. I've added up to 60 thou worth of shims to allow the outer races to bottom out first and allow free movement of the inner races. Anyone else run into this or maybe a p.o. has done some machine work in these areas?

MLW said:

When installing the steering stem and subsequently wheel hub bearings, I've found that the bearings will bottom out on the center spacers before the outer races reach the frame/hub lip.

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That's how it should be. The wheel bearing outer race should only locate against the hub shoulder on the lockring side. The inner race of the opposite bearing locates against the bearing spacer, not the hub shoulder.

Stem bearing replacement, section G6.

L.A.B. said:

That's how it should be. The wheel bearing outer race should only locate against the hub shoulder on the lockring side. The inner race of the opposite bearing locates against the bearing spacer, not the hub shoulder.

http://www.classicbike.biz/Norton/Repair/70up_Commando/70upCommando.pdf

Stem bearing replacement, section G6.

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Thanks for the reply!
Seems to me that would cause undue side tension and load on the bearings, after shimming, the bearings do roll much smoother. Perhaps unnecessary, or maybe some real benefit to this? Any Jap Bike I've done bottom on the outer race first.

MLW said:

Seems to me that would cause undue side tension and load on the bearings, after shimming, the bearings do roll much smoother.

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It doesn't as we would all be constantly changing our wheel bearings and other British bikes (Triumphs etc.) have the same single-bearing hub location.

MLW said:

Perhaps unnecessary, or maybe some real benefit to this?

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Unnecessary, because the method of single-bearing location if done correctly avoids the requirement to shim or for precision machined bearing shoulders. Adding shims simply moves the 'floating' bearing further away from the 'fixed' bearing (and the shoulder).
If it's smoother with shims then the floating bearing hasn't been set to the correct depth in the hub.