I bought a 36 hole 349 rim from SJS Cycles. This seems like serious overkill, a 16" wheel is going to reasonably stiff due to its size but the new rim is double walled and the wheel has far more spokes than is really necessary. l have the dual drive hub laced up the new rim now and the next stage is to get it tensioned which means fixing it into the truing jig. I didn't get any axle nuts with the hub but that's not a problem, I have some in my spares box. Wrong, the dual drive hub uses a 10.5mm thread so my standard nuts don't fit. What on earth was Sram thinking of, who in the engineering world uses a 10.5mm thread.