Acceptable Run-Out ?

I'm refurbishing a circa 1960 AMC gearbox for a Matchless G80 road bike. Overall the g/box looks good, light corrosion from moisture, no indication of broken gears, nor hard use.

Measuring the main shaft, I find approximately 0.004" TIR (Total Indicated Run-out), measured at the center of the shaft. The intended use is occasional day rides, no competition use.

What is acceptable TIR on this component?



Ciao,
Dick C

Hi Dick
I would put it between centres, as long as the centre holes are still both ok, and check both journals, the threaded end is more than likely giving a false reading.

Burgs

Burgs said:

Hi Dick
I would put it between centres, as long as the centre holes are still both ok, and check both journals, the threaded end is more than likely giving a false reading.

Burgs

Click to expand...

Ciao Burgs, thank you for your reply. Between centers is my preference as well, unfortunately someone with a hammer and a pair of vice grip pliers removed that option. Recognizing the threaded surface introduces an error was my next best choice.

Do you happen to know if Norton (or others) produced a standard for acceptable TIR on this component?

Ciao,
DC

Hi
Norton would have had tolerances that they worked to, 0.004" on a bronze bush might just be ok?
I haven't any Norton gear boxes apart, had a look at a Daytona shaft but it is a bit like yours, a gorilla has had a go and centres us.

Sorry I can be of no help.
Burgs

The factory must have had pretty worn out machinery if the runout is .004thou.

I would suggest the tolerances would be more like + or – 0.001 thou!