hub dynamo wiring - advice please

[NBC]

hi all

i'm building a shimano alfine 11s road bike for dad, (gates belt drive), he's asked for the hub dynamo,

i was planning on running the cable for the rear light through the downtube, and through the left hand chainstay, using dura-ace DI2 grommets each end,
what hole size will i need for the grommets ?

for the fork, i don't yet feel confident with internal routing, so i was thinking of using an old SS spoke and making small U shaped loops to use with zip ties,
that is just one thought i've had, yet if there are any other ways anyone has used to good success, i'd really like to hear from you :)

btw the fork is to be lugged steel, with a disc brake, and the lights will be supernova, with the front mounting at the fork crown

many thanks

NBC

[EricKeller]

there was just a discussion of this (on the email list, I think). I see no reason not to run it up through the fork. Put the holes on the neutral axis and you should be good to go. I'm about to do that for the first time, I'm sick of having wires all over the outside of my bike, especially the fork.

[NBC]

eric,

by the neutral axis, do you mean the side of the fork blade ?

i don't feel too confident with internal wiring yet, never even done it to a top tube, so feel that doing a fork blade might prove a disaster !

thanks

nbc

[blasdelf]

i was planning on running the cable for the rear light through the downtube, and through the left hand chainstay, using dura-ace DI2 grommets each end,
what hole size will i need for the grommets?

That's the best cable routing path, I use it myself where possible

The Di2 grommets are meant for a 6mm flush hole in the tube, which'll need a pretty careful reinforcement, but they do have a very nice exit angle

I highly recommend using coaxial cable instead of the normal scraggly wall-wart wire that comes stock with most non-Schmidt lights. I tracked down some awesome Mogami stuff meant for custom microphone wiring, it's normally a pain in the ass to get in small quantities, but a friend bought a big roll and is parting it out as a mitzvah: Coaxial Lighting Wire | Ocean Air Cycles

for the fork, i don't yet feel confident with internal routing, so i was thinking of using an old SS spoke and making small U shaped loops to use with zip ties,
that is just one thought i've had, yet if there are any other ways anyone has used to good success, i'd really like to hear from you :)

You figured out one of the best tactics: cut the head off a spoke, stick that end in the lower vent hole on the inside of the blade, and either braze a little socket for the other end or make it reach all the way to the top vent hole with another little hook, making it just long enough that it's under tension while installed. Attach the cable to the spoke using little sections of heatshrink.

Internal routing loose in the fork is a massive timesink, and means you need connectors outside the upper portal or inside near the bb shell if you want to be able to take the fork off without starting over.

Brazing in a little tube as a tunnel thru the blade tempts us all, but is oh so tragic when the insulation on the cable gets funky from trapped moisture, don't do this to yourself.

btw the fork is to be lugged steel, with a disc brake, and the lights will be supernova, with the front mounting at the fork crown

The Supernova Multimount is absolutely terrific for putting a light there

The Supernova lights themselves are unfortunately pretty awful compared to everything that's come out in the last 3-4 years, and quite unreliable. Sucks that they're the only euro company with mainstream distribution here.

If getting your own Peter White account is not in the cards, you can easily order B&M lights from xxcycle.com — I highly recommend the Luxos U or Cyo Premium for the headlight, and the Secula taillight (or Toplight Line Plus if you're using a rear rack). The Supernova taillight is sleek but unfortunately doesn't work with anyone else's headlights.

[NBC]

bladself,

that idea of yours with the spoke running all the way up the blade sounds pretty interesting, do you have any pictures ?

with the supernova lights, we currently have 2 pairs, and they seem pretty awesome, we have the e3 triple, wired to the top of the range nexus hub dynamo
what reliability issues have you had with them ?

many thanks

NBC

[blasdelf]

that idea of yours with the spoke running all the way up the blade sounds pretty interesting, do you have any pictures ?

Spoke used as dynamo headlight wire guide. by Passhunter, on Flickr

[blasdelf]

with the supernova lights, we currently have 2 pairs, and they seem pretty awesome, we have the e3 triple, wired to the top of the range nexus hub dynamo

The E3 triple at least puts out a solid amount of light unlike the single-LED ones, but since the beam is unshaped most of it is wasted on the sky, treetops, and the eyes of oncoming traffic — good for singletrack but not for the road

The Luxos U puts out fewer lumens, but 95% of that output ends up on the ground in a broad distribution with no hotspots, at 20m the patch is more than 4 lanes wide, and on a clear dark night I catch reflections off of street signs a km away!

The total light returned back to your eyes is far greater, and not in a big rosebud in front of your wheel that makes it harder to see stuff far away.

what reliability issues have you had with them?

I've seen a bunch where the standlight just stopped working altogether (not that it lasted terribly long to start with), causing the light to flicker incessantly and go completely dark when you stop

Supernova has great warranty support, and back in the day when there were huge advances every year they would install new LEDs for you on request, but you hope not to have to send your light back to Germany

[Gattonero]

Can post pics this evening the way I do with cable running outside, then you can have an idea how to run it inside the frame/forks

[Gattonero]

@Bladself:
can't see the need of connectors.
The wire from the hubdynamo does reach the fr. lamp where the connectors for the re. lamp will start, disconnect from there and that's it. Around the headtube you're gonna have the wires out of the frame and forks anyway.

As far the wire from the hubdynamo to the fr. lamp; the solution with the spoke looks neat, but I wonder if it's very steady, too.
I prefer to have the wire running more on the side-back of the fork blade, rather than properly on the inside

Dynamo_wiring16.jpg

Dynamo_wiring15.jpg

Dynamo_wiring13.jpg

Dynamo_wiring14.jpg

Dynamo_wiring12.jpg

Dynamo_wiring11.jpg

Dynamo_wiring9.jpg

But if you ask me, I'd rather depart from zip-ties. To minimize where possible, you see I run the wire+FD wire inside a sleeve that runs along the down tube.

As long as the wire is of good quality, moisture and passing the cable inside are a one-off job

[Thomas Norton]

As I am doing my first build with Doug Fattic I am going to run my wife (meant, wire) inside the fork blades. But I need an "exit strategy"! How to exit the top of the blade and how to snake the wire. Thanks!

[e-RICHIE]

As I am doing my first build with Doug Fattic I am going to run my wife inside the fork blades. But I need an "exit strategy"! How to exit the top of the blade and how to snake the wire. Thanks!

Welcome Thomas. I fixed that for you in your post!

[Peter Polack]

Welcome Thomas. I fixed that for you!

A Freudian Slip, I think.

[Jonny Cycles]

How to exit the top of the blade

However you want. Out the top of the crown, through the crown and into the steerer, under the crown, through a brake boss. The convenience of each location depends on where the light where be mounted. Some dyno hubs can be run in either direction, think about that. You might find some inspiration here - Flickr: The Generator Hub Bicycle Lighting Pool

how to snake the wire

Trial and error. Do be sure to make the hold big enough to use a grommet which will make things easier. If you get into a pickle you can use compressed air to blow a piece of thread through all sorts of twists and turns but I'd recommend planing the most direct route possible to avoid this frustrating step.

Good luck!

[EricKeller]

It's pretty tricky to exit the top of the blade since you didn't make provisions before assembling the fork. I think your only option is to drill a small hole in the blade below the crown. OTOH, Co-motion doesn't run SL wires inside the fork, they take it up the back. I would seriously consider that technique on this fork.