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DIY Internal wiring...

(10 posts)

  1. Dave
    Member

    Not for the faint of heart - you have been warned!

    Yesterday I finished drilling out my new frame and forks to accept internal wiring. I've made one small hole in the seatpost, another bigger one in the shadow of the reinforcing gusset on the down tube (at the head tube) and another in the fork (beside the brazed-on disc mount).

    This was easy.

    Next came the wiring itself. I would optimistically say that I started around 8:30pm and got to bed at midnight... it is unbelievably difficult because where the tubes hit the BB (or the fork leg meets the crown) there's only say a 1cm hole in the bottom of a 3cm tube.

    In the end I got there by passing a gear cable with both ends clipped off and then threading the wire through on those. But it wasn't easy even then, I had to put a kink in the end of the cable and use vice grips to rotate it so as to get the kink to pop out of the weld hole, and then my own holes were miserly / nervously small, making it very difficult to thread the wire plus cable through!

    The end result? Beautiful dynamo lighting with no exposed cables other than ~10cm by the fork crown. The power goes straight into the fork leg, splits at the crown to power the front light, down the down tube then up the seat tube, into the seat post, and thence the tail light :)

    So you can imagine my horror when I got to work this morning to discover that I had no rear light... disaster!

    Visualising another four hours spent tracking down the issue, I was relieved only slightly heartbroken to discover that the cable has failed at the three way join at the headtube, i.e. nothing to do with the internal routing at all.

    I think the mudguard vibrations may have torn the wire loose, which means I may need to file a notch in the bottom of the crown (or the mudguard) to keep it from repeating :(

    As a hidden bonus of fitting my thin Marathon Winter to the back wheel (which still required an extra link to be added to the chain), look what I was able to do with the horrible jubilee clip / inner tube arrangement on the rear brake reaction arm:

    Posted 12 years ago #

  2. wingpig
    Member

    Tidy. Hope you've not voided the warranty, though.
    I didn't realise there'd be continuity of internal space from the downtube to the seat tube. A similar technique could be used to get power to the front and back from a battery pack housed in a bottle or enclosure bolted to one of the cage-mounting points. Something to consider for the rebuild of my old frame, perhaps when the frame is bare for easier threading of a pre-emptive wire through it.

    Posted 12 years ago #

  3. steveo
    Member

    Neat.
    I had considered this for my dynamo light but I think your experience has sufficiently convinced me to stick with a battery rear and route the cable for the front through the head set. I'm sure the head set cap can take a small hole....

    Posted 12 years ago #

  4. kaputnik
    Moderator

    Very neat and very aero! This is exactly why I decided against the dynamo-powered rear light. I too didn't want a mess of cable strung along the frame, but wasn't prepared to go to such lengths as you have to solve the problem. And that's great you've managed to fix the compromised reaction arm arrangements.

    What's next winterisation upgrade for the WHITE FRIGHT?

    Posted 12 years ago #

  5. wingpig
    Member

    Is the metal bracing of brake cables electrically continuous? If it's going from handlebars to seat stays anyway, could it be co-opted to complete a circuit with the frametubes or would it be shorted through the rear brake's attachment to the frame?

    Posted 12 years ago #

  6. Dave
    Member

    @wingpig - I'm pretty sure that nobody will warranty damage caused by me drilling holes in their products!

    It's OK though, I can't imagine how it will have a noticable effect when the bike is so robust anyway (and full of so many other holes!)

    I don't have downtube bottle mounts on the underside of the tube, but if I did, they'd be much bigger and not in such a strong location.

    Re: using the frame and cables - something like that did cross my mind, but I read that conductivity of the headset makes even the frame part dodgy?

    @kap- it is a PITA. I think probably the time required to wire it is more than swapping out batteries for the life of a bike (so long as you always have spare batteries to hand, I guess).

    I can't think of anything else, now I just need to keep it going.

    Well, that's not quite true. I think I'll make up a spade-connected setup in the headtube so that if it ever gets snagged, it just comes apart..?

    Posted 12 years ago #

  7. splitshift
    Member

    i like !

    Posted 12 years ago #

  8. crowriver
    Member

    This is exactly why I decided against the dynamo-powered rear light. I too didn't want a mess of cable strung along the frame

    Presumably the rear brake cables have to somewhere (unless it's a coaster brake). Therefore there is an easy route for cable from the dynamo hub to the rear light as far as the rear brake, then along either the underside of the rear carrier or the rim of the mudguard, depending on the position of the rear light. SKS Chromoplastic mudguards even contain a conductor strip along the middle to supply power to rear mudguard lights (prone to corrosion on salty UK roads I would think though).

    Posted 12 years ago #

  9. kaputnik
    Moderator

    Presumably the rear brake cables have to somewhere

    One of the weird features of the frame is that the rear brake cable runs down the WRONG side of the top tube! meaning the cable has to cross-over it twice. I assume it may originally have been intended for a left hand front brake set up.

    But it would still need to be cable tied or taped on somehow as the brake cable is held neatly in place at either end by the cable outer stops.

    I didn't realise that about the SKS Chromoplastics, as those are the guards I have. I did wonder how I was meant to run the cable to the rear light on the guard.

    Posted 12 years ago #

  10. crowriver
    Member

    Interesting discussion on the topic of SKS mudguards and dynamo lighting here:

    http://forum.ctc.org.uk/viewtopic.php?f=5&t=17072

    I've been looking into this due to my tinkering with cheap bottle dynamo sets.

    Posted 12 years ago #

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