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cz battery box

Discussion in 'Modifications and Projects' started by Devery, Feb 17, 2010.

  1. i'm just about finished converting my 73' cz 477 175 from 6 volts to 12. now i need a battery. i was speaking with my auto electrician and he doesn't have anything small enough. same with battery world.

    the dimensions are;
    130 x 130 x 50 mm.

    speaking with the auto electrician, he said to fit the biggest battery i could fit in there. shame its a small space.

    does anyone know of a battery i can fit here? the bike is kick start only, i think this makes a difference?

    thank you.
  2. That's pretty tichy. However, with a kickstart only bike, you can take a few liberties.

    You don't need a battery specifically for a bike. You just need a rechargeable unit that can cope with a discharge current high enough to run all the electrics on your bike. To estimate this, add up the power of all your electrical loads and divide by 12. For example:-

    Headlamp 50W
    Tail lamp 5W
    Brake lamp 21W
    Indicators 2x21W
    Total 118W

    118/12 = 10ish

    Add a nominal (and very conservative) 5A to run the ignition and we have a max discharge current of 15A.

    Something like this would do quite nicely. Or two of these connected in series and mounted side by side.

    The only concern I would have is that a bike charging system tends to be able to charge at much higher currents than it's rated for, but, personally, I'd just make sure it was properly vented and keep an eye on it to make sure it didn't actually boil. I'd probably rubber mount it too, as a non-bike specific item may not be as resistant to vibration as a purpose made unit.
  3. I feel i'll end up just relocating it to under the seat... I will be able to fit a motorcycle battery and this will avoid future problems.

    Though... this is good information, so i will think about it. Maybe a future project?
  4. One of our mechanics at work has a CZ he is rebuilding to start racing this year, I'll ask him what he thinks in the morning. :)
  5. That would be fantastic. Thank you for that.
  6. What's he doing with the gearbox? One of the problems with tuning CZs was always that you couldn't go too far as the slow, clunky, wide-ratio box made it impossible to cope with the narrow powerband of a hot two-stroke. There were rumours of aftermarket gear clusters to solve the problem, but I never actually saw any.

    Or is it one of their dirt bikes, which were different, and rather better, animals.