1971 front wheel refitting

Assembly sounds correct, not unusual to have space between cup washer and lower fork(slider), rim should be central in forks, Measure it.Rim could be not fitted properly. I might consider fitting a full size washer between the fork leg and brake plate ,but this is NOT a recommendation as it should not be there.

Sorry but the assembly method is incorrect. It is OK up to fitting the "security pin" into the slot. Now check that the spindle is fully inserted into the right hand leg. Hand fit the wheel nut. (It is sometimes useful to have an assistant at this stage).

Now spin the front wheel as fast as you can and then apply the front brake as hard as you can. Keep the brake applied, DO NOT RELEASE THE BRAKE LEVER YET, Now tighten the wheel nut and then tighten the Retaining nut on the left side. This will centralise the brake plate thus making the brake more efficient. If you have a problem with a 3mm space between the fork end and the cup then it may be that you need to tighten the nut as I have described above, alternatively you may have a component problem. Have you bought/fitted a new spindle? Have your wheels been rebuilt? have you fitted new fork yokes (Triple trees for the chaps in the colonies). The bumping process you describe will do nothing to centralise the hub between the fork legs or to centralise the brake plate. All it will do is make a hollow "boing" sound.

Its possible that you have no problem at all appart from a rim that was not centralised. The pinchbolt fork leg is supposed to float on the axle to find its own position that does not put side loads on the staunchion bushes ,THEN its clamped in that position by the pinch bolt . This will leave a small gap between the leg and cup washer.If you have an abnormally large gap it could be that you have a fork brace/mudguard /yoke that is too wide or a bent staunchion,or too narrow wheel bearing assembly or incorrect brake plate /slider . Stainless replacement cup washers can be too thin and can also rub the hub.Two or three mm gap would not worry me.Is the axle a stainless one and a tight fit in the pinchbolt leg?,this would produce the problem and has been seen before. The pinchbolt stud can corrode into the leg and not fully release the axle and stop the floating action that needs to happen.I had to remove a stud once to cure this.But I don't think yuo have a problem at all,just being a worry wort!!.

I agree with Robert. I have examined my own Commando, Dommie and Model 50 after writing my last note. There is a gap on all of them between the Cup washer and the fork leg at the spindle. the cup washer is restrained by a shoulder on the spindle and so is never in compression by the bottom of the fork leg. So although you have a small gap here is the centre of the wheel central within the fork legs as it should be?

May be a stupid question but have you got the axle nut the right way around?

I changed the front wheel bearings the other week and on re-assembly I couldn't work out why the axle nut wouldn't tighten sufficiently. Took the 'Hamlet' moment and realised I had been a total a*** and had the nut the wrong way around...the moral of the story (for me) is that I mustremember to look for the simple solution first...good luck with the alignment issue!