My theory about the offside rear wheel bearing having loosened up in the hub was correct, as I discovered this afternoon after giving it a thorough check. I fitted the new, sealed wheel bearing on the drive side, no problems. But when I came to the speedo side the new bearing just dropped in, then fell out again. The hub was so worn at that point. Hence why someone had effected a 'cure' by shortening the distance piece, driving the offside bearing in as far as the stop in the hub, then added another bearing. I've now done the same... and it seems to have worked! A bit of a bodge, I know, but beggars can't be chosers, or is it losers? I certainly can't afford to spend any more hardearned dosh on the wheel!
I've been the proud owner of a 1965 BSA Bantam D7 since 1991, affectionately known as Little Willie (Wilhelmina) and love to take her out for a ride so that others can see her.