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Help! Motorcycle needs more .?

  1. Nov 25, 2009 #1
    Help! Motorcycle needs more.....?

    My problem concerns standard motorcycle 12v-6amp battery.

    I have a Yamaha Enticer 125cc. Standard electrica system with a approx. 44 watts total requirments for all lights, etc.

    What I need to do is add two halgon - 12v. 55watts X 2=110 watts to my system.

    Obvisiously the 12v -6 amp will not support the extra wattage.

    Can some please explain how to resolve this issue?

    I need to add two additional halogen headlights to my motorcycle.

  2. jcsd
  3. Nov 26, 2009 #2


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    Re: Help! Motorcycle needs more.....?

    Would this one work?
    http://www.apexbattery.com/yamaha-et340e-enticer-battery-1979-snowmobile-batteries-yamaha-snowmobile-batteries.html" [Broken]
    Last edited by a moderator: May 4, 2017
  4. Nov 26, 2009 #3
    Re: Help! Motorcycle needs more.....?

    Simply increasing the battery capacity is insufficient. The vehicle's charging system must be able to sustain the load without draining from the battery. Unless you intend to use the extra lights for only short periods, allowing time to recharge the battery between uses. However, that will dramatically reduce the longevity of a typical lead-acid battery.

    You may be able to rewind the stator coils to increase the output amperage. Look over these examples:

    You will almost certainly need to also modify the rectifier and regulator circuit/components to handle the increased electrical load.
  5. Nov 26, 2009 #4


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    Re: Help! Motorcycle needs more.....?

    Well, you wanted a battery that could provide more current but if your charger can't keep up, you have no choice to but find one that will do the job. Maybe the 125cc is to small to keep up. :biggrin:

    If it were me, I wouldn't want to take on rewiring a stator, but if it's been done before and works, go for it.
  6. Nov 26, 2009 #5


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    Re: Help! Motorcycle needs more.....?

    I'm with dlgoff on this one. Most likely the alternator volume wouldn't support re-winding anyway. Time to upgrade to a bike that has a more powerful electrical system. Otherwise, you run the extra lighting off independently-recharged batteries.
  7. Nov 26, 2009 #6
    Re: Help! Motorcycle needs more.....?

    Thanks everyone for the information.

    Since I live in India the cost to send the heavy duty battery (digoff) is prohibitive and the company does not ship internationaly for purchases less than $250.00.

    All the other information seems to be correct inline with what the Yamaha people tell me.

    I guess I will have to just add a seperarte battery and charge it from time to time.

    One more question please. Is there a better choice of battery to use than the regular acid type battery. Remember I have very limited space to add the second battery so it will need to be the approx. size of a regular motorcycle battery. I have approx.6"(w) x 12"(L) X 8" (H)space to fit the extra battery. Also since I live in India I may have limited choices as to different kinds of batteries.
    Any additional information would be appreciated.
  8. Nov 27, 2009 #7
    Re: Help! Motorcycle needs more.....?

    Well, as far as battery chemistry (Lead-Acid versus Nickel-Metal-Hydride, Lithium-Ion, etc.), yes, there are quite a few options for higher energy density, and lighter weight, but the prices are substantially higher. Your charging system would also have to be modified.

    Try looking at various manufacturers websites. Chances are they will have lists of their batteries' physical dimensions. From there, you can cross-reference battery model numbers through your local parts dealer.
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