Caliwild

Hey gang,

Looking to get a vintage bike/frame that has a fork that will allow internal wiring of a front dynamo hub... any ideas? I can't stand the sight of the wires wrapped around the fork (I know, issues...). Or, am I better off trying to find a new off-the-shelf steel bike frame? I tried checking the Velo Orange, Surly and Kona sites but can't figure out which frames will allow this... I saw a thread here about a vintage Koga Miyata bike that would work, but that would be like looking for a needle in a haystack. Thanks in advance!

wschruba

You can frequently sneak the thin 2-conductor BuMM wires through vent holes in the fork. If you have the light mounted to a conductive surface, you can even typically "get away" with one wire, provided the hub grounds to the axle.

Using vent holes (which I will admit: can be super frustrating) opens you up to pretty much every bike outside of the fancy-schmancy stuff where the builder was showing off, and silver-brazed the vents closed.

scarlson 

Pretty much no bike will have internal fork wiring from-factory.

Specialized Expedition had internal wiring, along with a couple of Koga-Miyata touring bikes from the '80s. Also many French randonneuses.

The trouble with all these is, they were built for "bottle" dynamos or under-bb dynamos, which won't run wiring down a fork blade.

On most all bikes that do have internal wiring, the wire is just running through plain holes, sometimes reinforced with a grommet or other such thing. It's not complicated to do this yourself, just very tedious. Even René Herse did his wiring like this. The wires are reinforced with braided sheath where they go in and out of the frame, and that's it. The only old builder I know of who used internal conduits is Jack Taylor, and then only on a very few frames.

I have threaded wires through a multitude of forks. Mostly Nishiki tourers (usually super easy), Miyatas and Univegas, a Huffy-era Raleigh, Schwinn Voyageur SP, as well as a Trek or two. You push a derailleur cable through from the top. Put a curved end on it, and either glue or solder the end to make sure it doesn't fray while you're pushing it inside. You push it all the way through to the bottom of the fork, then turn it until the curved end pokes through the vent hole near the dropout. Might take a couple tries to get the curved end right. It's got to be curved enough to poke out, but not so curved that it forms a U-loop inside the fork. Then solder the actual lighting wire onto the cable and use the cable to pull the wire through. It is often possible, except when it isn't. This will depend on the fork crown and pre-drilled vent holes.

Once I built a fork with an internal conduit. It was a HUGE pain to build. Would not recommend, not for the faint of heart. That said, it is super slick. The ne plus ultra of dynamo wiring.

With patience, you can be most of the way there by threading your own fork, if you find one with a hollow crown, with holes all the way through, and that is not super snaggy inside.

I favor a single-conductor wire over the two-conductor. Shimano hubs ground to the axle. Sanyo I think as well. SP and Schmidt do not, but you can ground them, like Peter Weigle did here:


I did this to my Schmidt and have had no trouble with single-conductor wiring. Cases where it might not work include plastique headsets such as the Stronglight B10.

nlerner

I've never tried to feed a dynamo wire through a fork--seems quite challenging! However, I have glued the wire in multiple places to the inside of the fork blade using silicon adhesive (so easily removable). You can pretty much make the wire invisible unless one were really looking for it.

Caliwild

Thanks! Definitely sounds above my pay grade, but looks good.

Caliwild

I like this idea. Thank you...

awac

R. Herse head wire

Thought this might be of interest, found it while surfing around a few weeks ago.

ctak

Some friends have drilled their forks and/or utilized existing lower fork drain or braze on "ports", with magnets to help guide the wire.

My '84 Centurion Pro Tour 15 had internal wire routing from the bb to the top of the downtube. Exit hole was pretty basic. Wishful thinking, but would love to see Son partner with SKF to offer a high quality square taper bb dynamo.

etherhuffer 

Look at some of the industrial supply places. You can get large heat shrink tubing in clear. You could either shrink bands of clear to hold the wire or slip over the whole fork leg and shrink it. Not sure how well that would hold up to abrasion would be my concern.

scarlson 

A BB dynamo that uses the rider's pedaling to generate electricity has never been done, to my knowledge. It would be interesting to know if it is possible, given the diametric constraints and (comparatively) slow rpm.

The Pro Tour is built for one of those under-BB dynamos that clamps between the chainstays, flicks on with a lever, and runs on the tire's tread. I always liked them, they seemed a bit more weatherproof than the sidewall bottle units. My childhood setup (thanks dad!) was one of those, but mounted on the front rack to run on the front tire, right next to the headlight. The tail light was a battery operated blinky. The "fancy" halogen headlight was pretty amazing compared to anything battery operated, at least that we could afford, back in those days.

Of course the modern hubs and LEDs are the 8th wonder of the world, in comparison to what we had then.

ascherer 

Nuts. I've been wondering about doing this and I now might be over the edge...

DiegoFrogs

I tried various ways to get a 2-conductor Busch & Muller wire through the fork of my Pro Tour, but couldn't ever manage. I could get it to enter each side, but never snake it through. Eventually I siliconed some small aluminum hobby tubing to the bottom of the fork blade after bending it to match the curve of the fork. I put one under the downtube, too. I run the cable through that tubing. The other part is under my plastic rear fender with silicone dabs and real aluminum duct tape for protection.

I did that 9 years ago, and it's holding up great. That also includes 2 transatlantic moves. As with all things experience, I'd probably be better with my silicone technique if I tried a couple times.

panzerwagon 

My ‘82 Chris Pauley Tierra has wire guides brazed to the fork blade. I’d still use silicone to secure the wires.


Chris Pauley Tierra, dynamo wire guide

bear_a_bug 

Another wire fishing attempt (sounds like a scam) I've used was to unravel a single wire from the braid of a brake cable wire. The single strand is just stiff enough that you can put a nice hook on the end of your fishing wire and get a bit more control. I then snake the wire through the tubes, pop it out the other side, solder on my electrical wire, and carefully pull the wire back out the way it came. Worked for me after some painful hours trying to get wire through a fork leg. Might work for others.

ChairmanMeow

As others have said, vintage tourers may have internal routing for a BB dynamo, but not for a hub dynamo. My Miyata 1000 has two sets of vent holes on the fork blade - one at the top and one at the bottom. As suggested by others, you could probably route a thin wire through those holes. My Specialized Expedition only has one set of holes (I think), so it wouldn't work on that bike - you'd have to make sure the bike you get has the double vent holes.

scarlson 

Yeah, I just worked on an early '80s Expedition. It has a solid fork crown so you can't snake through it. I ended up brazing on little guides made of very small diameter tubing.

52telecaster

I revisited the world of bb dynamos a year or so ago. It wasn't as good as I remember. Better than a sidewall for sure but nowhere near as good as a hub. Good memories though.

wschruba

The 'needle threader' method works well, too. Make a needle threader from the same strand of cable, stick it through the hole, and get another strand through from the other direction. Pull out, attach your wire to your new fish line, and pull through.

I needed 2-3 attempts to get the wire through in one piece. Using SON coax, it barely fit through the hole, and was one of the most frustrating things I've ever done; it took 2 tries to get it through the second vent. I gave up for sneaking the wire through the frame itself, and just used two-conductor BuMM wire...which fit in the crimped edge of the fender, anyway.