Dynamo Lights

This is probably the way I will go. I am loath to have mis-matched wheels (and the Velocity rims on my fixed are quite deep, so it'll show) but as a compromise towards utility it can't be beat.

I live in Coventry so the train to MK might actually be the same distance/duration as from London.

You could always rebuild it to your existing rim down the line if you get on with it.

I'd just give it a go. It's easy to get up-sold and procrastinate, when an imperfect but sufficient solution is available.

This comment

It's easy to get up-sold and procrastinate, when an imperfect but sufficient solution is available

identifies this thread (along with the mudguards thread, probs?) as the pragmatic and well-considered arm of LFGSS. Kinda want to have this framed in my D&T classroom.

Love this sentiment
I think it was in a rolls Royce brochure listing specs where under horsepower, the answer was ‘sufficient’

Seems more Citroen 2CV than Rolls, but an excellent sentiment for sure!

Why would the stand light feature light up the front light and not the rear?

The lights work so I don't see how I could've done something wrong but um isn't the rear red light meant to stay on, rather than the front?

Depends on the light most rear lights have their own stand light capacitor except for Supernova ones which rely on a Supernova front light for the stand light feature.
There are also Busch&Mueller lights with their shoddy engineering where some generations
just break.

Ah yes I'm drunk and couldn't remember the name other than it;s like SP but not SP.

Supernova. This is a Supernova set. I understand the front light contains the gubbins for the standlight and both "work" which is why it seems so odd the standlight is backwards.

Both, really, but the smaller rear lights have very little electronics built in and rely on the front light and its capacitor to store charge, which won’t work say if you’ve mismatched brands (B&M front and Supernova rear, for instance, like mine).
Edit, reading your second comment it should work really, have a play with the connections perhaps?

Yeah, I mean, I have a very similar setup on two other bikes so I don't see what I could've done wrong. Famous last words. No, the Germans did it wrong, for realz.

Did you just turn the wheel by hand?
The capacitor in the front needs some time to load. Go ride for a minute. Look again.

Nah, after a ride, the front still had some standlight juice but the rear was off. The rear works when riding though. Capacitor a bit shit perhaps?

Alternate/Switch cables of the rear light. The frontlight works on AC, the rearlight on DC. Capacitors only work in one direction.

I knew there was some DC going on but surely they use matching colours front and back?

I may have to check my partner's wiring work...

Yes. It's supposed to be matching colours. I don't know how the capacitor is wired inside. So to me it's also a bit funky.

But i suggest then, try switching cables at the hub connecter first. If that doesn't work switch cables at rearlight. If that doesn't work. Don't ever listen to me again or something's fucked.

I definitely showed her and said "match the wires" so I doubt she got it wrong. I didn't think it mattered about the front light to hub wires, then again, maybe I just read the manual better the first couple of setups I wired.

Supernova wiring. This tallies with my understanding of it.

Need to pull the wires off again and have a look under the leccy tape. Sigh.

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Colours should match, but only if the capacitor inside is wired correctly. Maybe the the rear cable outside the frontlight hasn't been wired correctly in factory

I'm definitely more inclined to blame us than the manufacturer but I'll know more when I strip the wires.

Front light to hub doesn't matter*. I'd expect the rear light to not work at all if it was the wrong way round, not for the standlight to be the only thing that doesn't.

(* unless you have an earthed dynamo, a conductive fork/frame and an earthed headlight, which I doubt the Supernova is)

Front light to hub doesn't matter

Yeah, that's my experience. Those little connectors don't care which cable goes in which side.

I'd also expect nothing from the rear light if it was the wrong way but that's still the thing I'm going to check, just for sanity sake.

I figured initially that maybe the cap has gone bad?

So, the wires are correct (because #hippyisalwaysright) and if they are reversed the rear light doesn't work at all. I guess that points to the cap being a bit shit in the headlight. Any other brilliant (your a lumen!) ideas?

I’ve been advised once to simply add a capacitor in series (?) to the connection, though a) I may be wrong and b) can someone more knowledgeable about wiring chip in please?
Yours, a regretfully electro-phobic technology Teacher.

It would have to be placed in parallel with the light output to do anything. Standard capacitors are spectacularly un-energy-dense so you'd want a super-capacitor for it to last more than a few seconds.

That's pretty much all the standlight in a basic rear light is, except there are usually some diodes and resistors and things to regulate the charging voltage and slow down the discharge current a bit.

My father is a electrical engineer. Pity he's just returned home! :)

I might email Supernova and ask about it but unless they're like "oh yeah, we made a bunch of fucked lights, send it back to us" I'll probably just suck it up and run a rear blinky.