I have consulted my informant on the shortcomings of the early telescopic front hub for sidecar use. He is probably the longest serving member of the AOMCC, having joined in 1952 or 53 and been a member ever since. Now in his mid 80s, his mind is a sharp as a razor and his record keeping on his bikes makes me positively ashamed of mine. His collection of Ariels is both interesting and extensive and his knowledge of Ariels is phenomenal. He does not have a computer and wishes to stay out of the limelight.
Anyway, to the problem. If you look at John Bryant's two photos at the top of this thread you will see that the early hub has an extra cooling ring before we get to the spoke ring on the brake drum side. The spoke ring itself on the brake drum side is bent backwards away from the drum. The effect of these two factors is to move the spoke heads on the brake drum side a considerable distance towards the centre line of the wheel itself. The net result is that the brake drum side spokes are much more vertical and so are unable to take as great horizontal loads as spokes which are more inclined, as they are on the later hub. So when you take a left hand bend at speed on your sidecar outfit with the early type hub the brake drum side spokes cannot give an adequate amount of sideways restraint. This means that the opposite side spoke heads become slack and push into the tube. The end result is either spoke breakage or a front wheel puncture from the spokes on the inside of the tube, neither of which is good for the health when taking a left hand corner fast on a sidecar outfit. Hence the re-design of the hub. My informant suggests that the surplus early hubs were used up on 350cc machines on the grounds that these were unlikely to pull sidecars.
Good news for David Anderson though. As you are using your hub for a sidecar wheel, it does not have to be built with the rim central to the hub. So you can offset the rim to obtain equal angles from the vertical for the spokes each side. That should give sufficient strength to avoid the problems described above, particularly if you use as small a rim diameter as you possibly can. My informant has thought about your particular problem all day David and rang me back this evening with this advice.
36 4G, 37 VH, 53 ex ISDT KHA (project), 54 KH(A), 54 4G Mk IV (project), Healey 1000/4 (project)
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser.