49cc 6v wire from magneto question

Chrisbull420

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Apr 20, 2020
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I have an all stock, 49cc Chinese bike kit. I currently have cell battery powered rear lights but I am always having to charge them. I would like to run a red light from my magneto, the white 6v wire. First off, I can only find 12v lights. Will I be able to still run a 12v red light on my bike? I assume the lumens would be alot lower, but I just want a red light. Second, I heard it affects the hp for the engine. True?? If so, how bad and is it worth it to run the light. Ty in advance!!
 

Larry Trotter

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Nov 26, 2017
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I would look at using a red led and a current limiting resistor of some kind. Or a led light bulb for a turn signal. If you draw too much from the line it will effect the ignition. It’s probably AC but the led bulb will likely work.
 
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Chrisbull420

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Apr 20, 2020
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I would look at using a red led and a current limiting resistor of some kind. Or a led light bulb for a turn signal. If you draw too much from the line it will effect the ignition. It’s probably AC but the led bulb will likely work.
Thank you
 

Larry Trotter

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I will add some thought on this. That 6 bolt wire is almost certainly AC voltage and isn’t regulated to 6 volts in any way. I would get two large super bright red led’s and about a 30 ohm resistor about a 1/4 watt should do. Wire the two led’s back to back with each other the long lead to the short lead of each. They will only light with the ac one way and this will light both of them. Only one current limit resistor is needed in line on either the lead going to the wire or to ground. 30 ohms is only a suggestion 50 or 20 should be ok.
 
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Chrisbull420

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Apr 20, 2020
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I will add some thought on this. That 6 bolt wire is almost certainly AC voltage and isn’t regulated to 6 volts in any way. I would get two large super bright red led’s and about a 30 ohm resistor about a 1/4 watt should do. Wire the two led’s back to back with each other the long lead to the short lead of each. They will only light with the ac one way and this will light both of them. Only one current limit resistor is needed in line on either the lead going to the wire or to ground. 30 ohms is only a suggestion 50 or 20 should be ok.
Thank you very much
 

Greg58

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Most all parts are interchangeable, on the bottom end except crankshaft,piston and cylinder. Magneto, magnet,clutch are all the same. All bottom end cover gaskets are the same.
 

Greg58

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Will that work on his 49cc?..........Curt
Curt are you talking about the 49cc 4-stroke? If so no, only on 48cc 2-strokes. I have never tried one but by it's design it should work just like the ignition mag. I would run a small sealed 12v battery to keep constant lights.
 

curtisfox

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Dec 29, 2008
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Thanks his is a 49cc china engine, that is why i asked. But also have a old china 2 stroke setting in the shed, still in the box ( son needed money, so ) Thinking also doing it this summer with belt drive instead of chain.........Curt
 

curtisfox

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Prof you don't need a big engine, LOL My old Monark twin was a small engine and road the snot out of it...........Curt
 

Citi-sporter

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Jun 16, 2014
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I was just going to note: If this is a recent HT engine, ( 2017 or newer..) the white wire is off of the ignition coil and is no longer 6 volts. It's closer to about 60 volts and with some fudging around can run a cell phone wall wart at higher rpms. If your light is USB charged you could experiment with 500 mA 5 volt cellphone switching chargers and see if the engine still runs with the wall wart in the circuit. My experiments show that it does work with lower output wallwarts but they shut down at lower rpms. My experiments have shown that the engine still idles reliably with the charger