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I was wondering how motorcycles work with no battery? They need battery for Lights etc, but i know they dont need a lot of battery for kick start, only for lights, for electric starter absolutely needs battery... the point is how they run with no battery it doesn't make sense to me lol
 

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There are a couple of ways. One is a magneto. Its a self contained unit that generates its own spark. Has its own points. But it won't power lights. Virtually all bikes today have an alternator to generate electricity. It goes to a battery and you know the rest. Thee are "battery eliminators" that do away with the need for a battery but you won't find them on electric start bikes. Some bikes from the 50s had flywheel magneto/generator that also powered the lights. No battery but the engine had to be running for the lights to work. This is a very simplified explanation. But you don't need a battery for an engine to work.
 

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The alternater will run the whole bike including lights as long as it is running. You can start it and then remove the battery and still ride. You need power to activate the alternator and starter but from there on it's not a necessity. My XR runs off a magneto and needs no wires at all to run, only one wire for the kill switch.
 

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of course the exeption are bikes that require a charge to polarize the magnets in the charging system. Those require a battery to run. some 70's hondas are like this (the SOHC cb750 for example). If you want to run one of those without a battery you need to change out the charging system.
 

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What kind of bike are you considering doing this on?
 

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My '75 CB360 uses a battery eliminator from Oregon Motorcycle Parts. It's just a very large capacitor that connects the same way as the battery and when the engine is off, the capacitor slowly discharges in 5-6 minutes. The headlight & tail/brake light work OK but flicker, especially at low RPM. If the lights are on and the RPMs drop too low, the ignition dies but it doesn't happen when the lights are off. The bike will run without the eliminator so I'm not sure how much difference it actually makes. I don't have a starter but when I kick it the engine typically starts on the 2nd or 3rd kick, which is the same as when it had a battery.
 
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