Another post elsewhere suggests that where fitted it is of benefit to change the splined hubs occasionally, presumably to account for wear over time. This cuts across my long held presumption that the tapered joints of the hubs 'lock' when tightened & so there is no contact or wear in the actual splines during normal use. Has anyone definitive advice as to the working principle, maintenance & long term care of splined wheels & hubs?
Thanks Guy

It's best to think of hub splines and tapers as serving different purposes. The function of the tapers (inner and outer) is to locate and centralise the wheel on the hub, the splines transmit (and resist) torque. The tapers are not essentially of 'locking' form - if they were you'd have the same trouble removing the wheel as you do removing a rear hub - nevertheless it is possible that they can share part of the torque load. The problem is that they do not form a positive rotational lock with the hub; if there were no splines present heavy acceleration or braking could allow the wheel to rotate relative to the hub with potentially disastrous consequences!

The usual indication of spline wear is a clunk from the rear end; unfortunately this could arise from a number of sources in the transmission. If you suspect spline wear, remove the wheel and clean the splines on both wheel and hub. Remount the wheel but don't fit the centre lock nut and with the brakes on, check circumferential play at the tyre periphery; anything more than about 4mm can be cause for concern and suggests that either the hub or the wheel, or possibly both should be considered for replacement. Identifying whether it's the wheel or the hub splines that are worn can be a time consuming job.

wear in splined hubs is a common and often overlooked issue .. fortunately the threads are 'handed' so the likelihood of losing a wheel under braking is mitigate somewhat.
there is information on several sites that sell and service spoke wheels as to what to look for to determine if there is wear :- one basic check is ( after thorough cleaning of the splines) to look carefully at the profile of each raised spline.. they should be even in profile with side of the raid pint ... when worn they develop a slight 'slope' to one side. Another basic check is ( again after a good clean..of both wheel and hub splines) is to fit the wheel and see how much it rocks on the spline before tightening ..much like testing the wear in a king pin.. often light wear on hub splines can be countered by replacing the wheel with new one.. this is NOT an area to take chances.. if in any doubt, get a second opinion from someone who has experience with spoke wire wheels ..

The characteristic sign of worn splines is that they become "sharp" i.e. v shaped at the top. Splines in good order will have a flat rather than a sharp top to them