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Does anyone know what the acceptable runout is for this shaft? Dial gauge on the nose of this (where the clutch cover support bearing would go) This is a brand new SC CR gearset with new bearings used throughout and am getting .018" runout which to me seems excessive, all bearings are home correctly and there seems very little play in the bearing assembly, I can push it to a maximum deflection of .006"
So to me something seems amiss just interested in other peoples thoughts. Contacted the supplier who said theyve encountered no issues and recon once the flywheel cover is on it'll be fine. I would add that the 1st motion gear/syncro teeth runout is the same within the box.
I guess I best have it all apart again and stick on a lathe with dial gauge to be sure, almost as if something has been machined not central.
Or am I being too fussy!?
Also with the middle drop gear in situ the backlash obviously varies from acceptable to minimal between the 1st motion gear and the drop gear.

18 thou runnout, is insane should be dead nuts, less than a thou........

BWA's got it dead right again........ I suspect that somewhere in the dim and distant past some 'technical author' somewhere has dreamed up this figure, due to expansion coefficients, metrication, moon phases and EU exchange rates. .001 when cold is all that's needed in my opinion otherwise it'll be slopping back and forth like a spare prixx at a tarts wedding. Talk of expansion in this application is based on fuzzy logic.

Just put a Mini Spares 3 sync straight cut 1St Motion Shaft between centres in my lathe. Basically 0 to less than .0002 runnout on any measurable surface.......

Even the synchro cone surface, which, surprised me, because, it's kind of a grainy sprayed on surface, and, I wouldn't have been surprised to see a few thou here and there on it........If anything, it was the most true of all the very true surfaces.....

Yes, I would never have thought, so it's either the shaft itself or a bearing issue. Will whip it out and stick it on the lathe and put the gauge on it and see where it's at. This is a MS gear. Will report back. I do have a video but am unsure if it can be uploaded.

Just to be sure, fit up the Input Gear and Torque up the nut, but anymore than 0.003" (even then, I wouldn't be happy) and send it back.

Just stripped it down completely and put it back together again after checking the input shaft on the lathe, all was good there and it's fine with at most .002 runout and I can deflect that easily, drops are fine with the same backlash all the way around. Bit of a mystery to be fair, the only thing I found was I had overshimmed the FD gear end by a nats whisker which would I assume potentially cause an issue possibly as I found as would force the gearstack towards the 1st motion gear/shaft assem but apart from that I couldnt find anything else wrong, it all turns freely, can select gears and feels nice with no slop!
You'd think that the amount of boxes I've done in my time I'd have got that aspect right!! Put it down to old age!!! Thanks all for your help