The real BMW classics from fifties to Earles fork types had cast iron hub centers, not alu as from /5 series - with their problems of wearing bores. These cast iron hubs were designed for heavy sidecar use like frames etc. , so you did not set preload on the taper roller bearings. In fact you had the bearings with inner and outer spacers mounted with axle and nuts in one hand and checked the outer spacer for just being able to shift sideways by thumb pressure so nil clearance but no preload as well. So after this check you then mounted the lot into the iron hub. There was rarely ever any oversize worn bearing seat in these hubs with cast iron and the Earles fork BMWs were more or less the best bikes ever made for sidecar use, for some more reasons too.
To be open, I do not see a reason for having play in a Vincent alu hub, there should not be much of a temperature rise around bearings when all is right. So why have play there from the beginning, brake heat has to go a long way to reach there ?? Vincent S. has confirmed that no corrrections were necessary for temperature effects. I wonder if anybody has ever touched hubs for heat from typical road use ?
Vic
