Kinetics 8-speed SA fitting

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srw

srw

It's a bit more complicated than that...
I have just looked at your photo in the OP and, goodness they are quite literally all facing the same way with heads out one side and heads in the other. It is as though the wheel builder just dropped all the spokes in in one go from one side. I wonder if @Yellow Saddle knows of a good reason why they might have done that.
I know very little about wheel-building, but I know that it's normal to alternate innies and outies (which I think @Pale Rider's wheel-builder did). I don't really understand what @Yellow Saddle is saying (sorry - it's not your fault), but I think (s)he is talking about a wheel-build where the spokes are laced around each other. One of the things I learned back in the late 90s when I first got a Brompton - at a time when Brompton themselves were still learning how to build wheels, and being a heavy customer I broke spokes with monotonous regularity - was that lacing small wheels isn't really necessary. (That spoke-breaking problem was solved first by me finding someone who realised that mini-washers acted to reduce play between the spoke and the hub and then by Brompton realising that a spoke with a much smaller bent bit than usual worked well with the relatively thin flanges of a SA 3-speed).

The wheel I got this year wasn't laced, but having all the heads on the same side meant that every other spoke was at a very awkward angle in its hub hole, and I think that created points of weakness. By alternating head direction I've now built something 1X where crossing spokes don't touch at all - which is just like the Brompton dynamo hub front wheel and the 3-speed rear I've got.

The hub diameter is enormous - it's got something like a 20-tooth sprocket on it, and the hub is a fair bit bigger than that. I've used 126mm spokes, which isn't quite as small as SJS goes, but is pretty close. Fortunately I did extract that size out of the vendor before he failed to send me the replacements he promised....

One of the things that I've found frustrating, being a thinker not really a doer, is that all the tolerances are tiny. There's only just room for the chain to pass between the sprocket and the tensioner, and likewise between the gear adjuster and the chain tensioner.
 

Pale Rider

Legendary Member
electric-brompton-260-watt-crystalyte-motor.jpg
Like you, I don't get the physics of wheel building, but the 'awkward angle' some of the spokes leave the hub may have something to do with your problems.

There's a similar theory for hub motor ebikes as to why spokes break, the large diameter motor causes the same awkward angle of exit.

I've seen an after market Brompton hub motor wheel on which the spokes are simply radial - no cross over at all.

Looks odd, and I've no idea if it works any better.

Edit: Pic added in the wrong place, but at least it's there.
 
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