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Discussion Starter #1
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So.. Not my first build, and hopefully, not my last. The bike was a basket case that sat since 2004. Added dual front brakes, stage 2 dynojet needles with 155 mains and K&N pod filters. Sucks gas like a Cadillac but it feels like my full-race Triumph TT special... (hang on for dear life when it hits its power band.
 

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BTW, I'm thinking about replacing the lead acid battery with a Li-ion battery but the existing alternator is a single phase unit. Does anyone know if it's a working solution to add a couple of high value caps, say 1000mfd across the battery to help eliminate ripple and make the Li-ion battery think it's got a 3-phase alternator instead of a single phase unit?
 

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BTW, I'm thinking about replacing the lead acid battery with a Li-ion battery but the existing alternator is a single phase unit. Does anyone know if it's a working solution to add a couple of high value caps, say 1000mfd across the battery to help eliminate ripple and make the Li-ion battery think it's got a 3-phase alternator instead of a single phase unit?
With what rectifier and regulator? The Velocette!

Put an oscilloscope on the voltage regulator rectifier output and see how dirty it is to begin with, then add about a 16 volt 10000 mfd cap to see if it cleans up the output any, I would be skeptical of any improvement unless you upgrade the rectifier. Might get the exact same effect by just adding a second Li battery. The reason the 3 phase is working better is because it is literally producing 3 times the raw power, old motorcycle power rectification and voltage control was mostly about dumping off excess energy in some form of heat.
 

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The new battery is for the Ducati. I assume the stock rectifier unit is based on Zeners. Good idea about using the scope. Don't know why it didn't occur to me.
 

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So I looked at the alternator output across the battery... pretty egregious... big-time ripple at about 50% duty cycle. I put a 12,000 µfd cap across it and it did absolutely nothing. I gotta say, I was kinda surprised. I expected something, especially at idle when the output voltage is low.
 
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