Generator Light ?

Discussion in 'Electrical' started by KDC1956, Dec 25, 2008.

  1. KDC1956

    KDC1956 Member

    Does anyone have a pic of there bike with a generator light on it.I got one for christmas and I don't know how to install it.A good pic should let me know how.I hate to ask for help on anything.But after looking half of the night for info on how to install I give up.I feel like a :dunce: lol.

  2. bluegoatwoods

    bluegoatwoods Well-Known Member

    Well, even if there's some photos out there it's not likely that they'll be clear enough to be of any help to you. But you shouldn't be shy about asking for help; that's one of the reasons we've all joined this forum. And whoever has the answer you need is going to be glad to help.

    I'll make a small stab at it. So are we talking about one of the old style "bottle" shaped generators? The type that is driven by rotating into the side of the tire just above the wheel itself? Or is it some other type?
  3. KDC1956

    KDC1956 Member

    bluegowoods yep thats the one I am talking about.I'm not sure if it goes on the back or the front or left or right side.
  4. spunout

    spunout Member

    doesnt matter. anyplace that it rubs on the tire is fine.
  5. Generator

    Hi we always used to mount them, rear tire up high, behind fork leg I think.

  6. mabman

    mabman Member

    The proximity to the wheel that that type of generator needs makes me extremely nervous that if not done just right it will end up in the spokes and then, well you get the idea? I wonder if you could rig a sprocket on the end cap and mount it so it hits the drive chain?
  7. bluegoatwoods

    bluegoatwoods Well-Known Member

    And use the generator as the chain tensioner? It's a neat thought. I think maybe that idea came up in another thread recently.

    It might be moderately difficult to engineer it to work properly without destroying the rear wheel. But it shouldn't be too much for some of the bike engineers who post in here.

    Now picture the generator being a bit bigger than those ones we had as kids. There might be the equivalent of a happy time alternator. sickbikeparts? sounds like something to add to your catalog.
    Last edited: Dec 26, 2008
  8. loquin

    loquin Active Member

    Those 'bottle' generators are notoriously inefficient (causing a lot of drag, even when you're not using the light,) and usually of pretty poor quality. They also can't stand much in the way of side-thrust, so I don't think that they should be used as a chain tightener... There are some German wheel-rub generators which are pretty efficient, and are much higher quality, if you can find them.

    In addition, the output voltage is very sensitive to the generator RPM, so if you're running at much over 10 MPH, they tend to blow the bulbs in the lights.

    Since a MB can run quite a bit faster than 10 MPH, you'll probably want to make the rub wheel larger - maybe glue a short piece of thick rubber tube around the rub wheel, or even make one of wood or plastic. (Just be sure that the new 'tire' has a rough surface to avoid slippage. This larger diameter 'tire' on the generator will reduce the drag you experience.

    The other alternative (although more expensive) is to get a dynohub & build a front wheel around it. They're very efficient (meaning that you will barely notice that they're there, even when peddling with the lights on,) have virtually no drag when they're not being used to power the lights, and their output voltage is much more stable, over the whole speed range than a bottle-type generator. The one I've got even has an internal drum brake built-in.
    Last edited: Jan 21, 2009