Originally Posted by
unterhausen
I drilled my access hole in the middle of the underside of the lower head lug, like everyone else does. I don't see why you would drill it on the side. Maybe people think that's the neutral axis, but it's not.
Nobody can see the underside of that lug. Just make sure your drilling process is good.
thank you — I’ll do it from the underside then. Any specific advice on what will constitute “good” drilling here? I’m not new to drilling into steel but I am in an apartment and have mediocre tools. So I was just going to start small, use metal grade newish bits and generally speaking just be careful.
Originally Posted by
base2
Sometimes, on some forks, the bottom of the steerer has a hole clean through big enough you can stick your finger in. If you grab a flashlight, sometimes, about a half to 3/4 inch up, there is a hole in either side where the fork blade mates.
If you are lucky, you can feed the dynamo wire up the drain hole at the drop out. Then up the blade & out the hole in the top of the leg & out the bottom side of the steerer. You might find that making a loop with some 20 or 30 gauge magnet wire & inserting it in the vent hole from the bottom side of the crown so as to "catch" & extract the dynamo wire will help with your goal.
As you can tell, I'm not a big fan of drilling holes in things, but if you are lucky & have perserverance you may be able to at least run the wire up the fork leg. From there, just run the wire along a shift or brake cable & save yourself the trouble. Dynamo wires are small & easily broken enough that you'll be changing it frequently anyway.
yes, the Raleigh has a generous drain hole by the fork dropout and there is some hope of being able to run a wire up the fork. The problem is that I could not have the wire come out again at the crown because in my builds the crown is usually “plugged” by a daruma for a fender. But, in general, I am not very concerned about the first wire section (front hub to front light) as it can also crawl on (or even in) a stainless steel front rack. The problem I am trying to solve is the down tube: zip ties, tape and the likes aren’t allowed. If I cannot drill cleanly I could consider gluing the wire carefully to the underside of the down tube but that seems less elegant.
Originally Posted by
unterhausen
I took the op to mean getting from the fork to the main triangle.
Correct.
Originally Posted by
base2
Going from internal to the steerer to internal to the frame would require a hole from the steerer to the inside of the head tube. (As I gathered from the op) The amount of wire flex there would be insane. If the wire lasted one ride, I'd be surprised. I would not recommend drilling a hole in the steerer to let the wire out so that it could be routed down the inside of the downtube.
A gas pipe Opafiets I rode in the Netherlands had a hole drilled in the down tube a few inches from the lower head tube lug for internal dynamo wire routing, but the wire was broken at the hole & never replaced. I suspect all internal routing would suffer the same fate.
The “all internal” routing you suggest seems cool but I am not sure you would be able to turn the steerer (you know, in order to steer the bike!) without essentially having it work as a scissor and cutting the wire off. On the other hand, I don’t see why you think the wire in the down tube would be particularly fragile. All I am planning to do is to drill the lower head tube/down tube lug so that a wire (originating at the front light, on a front rack) can travel inside the down tube until the bottom bracket shell, where it gets pressed into the rolled steel of the rear fender until the rear light.
This system was a standard feature on many touring bikes of the 80s and it still is a standard add on for most of today’s custom builders here in the US. I have a 1984 Centurion Pro Tour with the 36-years old dynamo wire in the down tube, pre-installed at the factory, still going strong. Maybe I’m missing something, but surely the wire feels safer in the tube than out!