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If the bike runs: measure the A.C. voltage output from the blue/white wire to ground, the green/white wire to ground and the yellow wire to ground, right from the connectors where they come out of your engine.

If the bike does not run: when the plugs are disconnected measure the resistance on those three wires to ground and it will likely be only a very few ohms, but there will be measurable resistance.

You just tested your alternator outputs :cool: and hopefully all of the readings are near identical or you may have a problem.
Proper testing procedure to be sure but I will be willing to bet that the alternator is putting plenty into the smokey mess that used to be your battery. As completely uninformed of the nuances or modern lithium batteries I was and am it still sounds as if the alternator is putting out fine but overcharging the battery.

In my ignorance I do know that most of the lithium battery manufacturers suggest that you use a special lithium battery charger Shouri who helped us some, makes their own chargers. I can't say for sure but I was given three of their chargers and those are the ones I have been using on some of the race bikes. Two of those motorbikes have batteries that are at least 4 years old and show no sign of weakness or failure. This is while three of my street bikes also have Shouri batteries and two have been in need of replacement. Now these bikes do get ridden over rough roads and I often use electric riding gear to keep warm when nature refuses to do the job. I also use a radar detector to keep cool so those bikes do get a wee bit more abuse but they also are parked and have the batteries on Battery Tenders. There is no science here at all just my experience but may be worth considering. :unsure:
 

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The coils inside your alternator (3 of them for a 3-phase alternator) are nothing more then a very long piece of copper wire wrapped around itself and insulated with something that resembles varnish.
If that varnish breaks down, the windings can touch and now your coil has a completely different length. Or one of the 3 windings can dead short and now you only have 2 windings attempting to carry your electrical load.

The alternator in combination with a rectifier (which converts the AC power to DC) and the regulator (that serves to limit the voltage output) is what make this assembly now called a DC output generator.

You know the old saying garage in, garbage out! If your alternator is not putting out the correct and expected form of electrical power, no amount of power rectification or regulation can fix that problem.


Lithium batteries suck in sub-zero cold weather and they are extremely expensive. Lithium batteries are not tolerant of over-voltage, even brief voltage spikes that your multi-electric meter can not detect, but can be seen using an oscilloscope, are enough of an issue for your solid state battery to be adversely affected. It's a solid state battery!

It's the liquid (water) in a lead acid battery that makes it able to dissipate excess heat :geek: it boils. Solid things don't boil so well, they will look just like those photos of expensive melted batteries.
 

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In summary, any Lithium battery will require a stricter voltage control than AGM or lead acid and old style regulators/rectifiers were not good enough. Get a MOSFET from Sparckmoto. Matt there really is the go to person for all your vintage bike electrical needs. Charging and Regulators - Sparck Moto

One other thing to note about Lithium based batteries is that they don't like the cold and need a little warmth to get them up to full power. Often they will need the lights turned on or a few short stabs at teh starter button to wake them up.

Good idea to test the alternator anyway as suggested by trials.
 

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Sorry guys, but putting a lithium battery and LED lights on a 1970's /early 80's motorcycle is a bit of a joke, these were not purchased as race bikes,
they are trying to save weight :/ those bikes were built heavy from the ground up, these same "builders" run with the stock peg mounts and steel rims made heavier with powder coat etc. etc.
They are putting the lithium battery and LED lights on these relics for no good reason and frequently before they even have a running motor. Sheeple
 

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Sorry guys, but putting a lithium battery and LED lights on a 1970's /early 80's motorcycle is a bit of a joke, these were not purchased as race bikes,
they are trying to save weight :/ those bikes were built heavy from the ground up, these same "builders" run with the stock peg mounts and steel rims made heavier with powder coat etc. etc.
They are putting the lithium battery and LED lights on these relics for no good reason and frequently before they even have a running motor. Sheeple
TR, Sometimes you race a motorbike of that generation because that's what the rules dictate. Classic SBK rules say no newer that 1983, no USD forks, no larger than 41mm no flatside carbs. Ours are a tribute to the Superbikes and Endurance racers build by Yosh and ridden by Wes Cooley and Grame Crosby. The rules do not state a minimum weight or where on the hulk that weight may be. So one makes the whole wretched mess as light as one can and puts the weight where it best lend itself to the handling you are looking for . All part of the challenge thus part of the fun.
 

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Or you grind down parts that are too thick and fit lighter, newer parts. Old incandescent headlamps tend to be dull and yellow and suck all the electrons out of a battery and old alternators are not able to replenish supply. I have zero hesitation in changing parts and upgrading them to work better. Some of us have been doing that for years.

We can't necessarily replace thr frame with a chrome moly custom piece, but the spirit of customizing has always been to make the bike into a version that better matches your vision of what it should have been. All bikes are a compromise - performance for comfort, style for functionality and so on. All we do is to try to tip those scales a little in favor of our preferences.

If I can drop 100 pounds off an old bike and add 40-50HP I am a happy chappy. Would that bike ever come close to say a modern sport bike? Not in anyone's dreams, but that's not what I'm trying to do, and I suspect that's true for most of us.

As to rules, in racing it's up to us to interpret those rules to our best advantage. Some have deep pockets and can buy the best. The rest of us just keep stretching the proverbial envelope.
 

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Competition rules change all the time, been doing it fore well over 25 years, today's modern is tomorrows obsolete, but to me if it's not pre-65 it's not even worth riding it in vintage competition.
Get enough guys together and you can start your own racing class, make any rules you want, that's the reality of it, all it takes is time, money and interest by the right people.

What we do in competition racing with motorcycles is sadly irrelevant to most of the bobber choppers that come through here, cafe racers they aren't and race bikes, even less, most times they are fat wheels art projects assembled from Amazon dot com parts.


... you could run a lithium battery in a race bike on a dead loss and not even turn a generator, save all that power if your battery does not go flat before the required laps,
you can't do that on a street bike.

These guys don't even have freakin fenders on their bikes, 80% of them claim they like the way it looks and they never ride in rain, these are not people that ride after dark, they aren't upgrading their headlight because of colour temperature, it's a fad. Sheeple fad, right up there with pod air filters :LOL:
 

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I don't ride in rain. I don't ride at night.
I use LiFePo4 batteries when I can.

I dont really see them any different than regular batteries other than making sure your regulator is updated.

I'm not sure what the issue is? They aren't crazy expensive. I can think of dozens of things that cost more and do just as little. Lol.
 

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on the other hand, I see your point...

Sorry guys, but putting a lithium battery and LED lights on a 1970's /early 80's motorcycle is a bit of a joke, these were not purchased as race bikes,
they are trying to save weight :/ those bikes were built heavy from the ground up, these same "builders" run with the stock peg mounts and steel rims made heavier with powder coat etc. etc.
They are putting the lithium battery and LED lights on these relics for no good reason and frequently before they even have a running motor. Sheeple
 

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on the other hand, I see your point...
Sorry I don't really see TR's point. I'm more about, if you are having a good time at the two wheel adventure ; more power to ya. Cause if you are just looking to get to the corner store an old Toyota Corolla will cost less get better fuel mileage and you will not give a damn if it rains.

I'm sure not traveling across the big water to help my Mates race on narrow country roads because it even borders on being a smart thing to do. We build motorbike that comply to the rules where we want to compete because that's what we want to do. So pardon my lack the intellect that allows me to understand your condemnation .

Anyway Cheers
 

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Sorry I don't really see TR's point. ...
Stick around for a few years and watch what comes through here. Very few are race bikes, many are none ridable art projects. I definitely picked the wrong thread to discuss it, and apologies to the OP for that, but lots have come through this site and been alerted to the hazards of mix matching technologies on their bikes, few really want to hear what caused or will cause the problem, none want to hear the correct solution, they just want to order the part that fixes it off the internet and have somebody tell them what carb jets will work now they have removed half the exhaust system.
 

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I think it's the bikes that TR usually rides that is the "issue"...

Light is another world in trials riding. Of course it would make sense in a modern sportbike and track builds where the purpose is to create a better handling bike at cost.

But for a 500+ pound 70's bike that is being modified for looks alone, as many are these days, it makes less practical sense.

 

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Here, some of you guys might have time to watch these things, I don't
plus I don't need to, I already know what they are going to say :|


Sorry Mate no offence was intended. I will admit that the reasons I enjoy the "modern" vintage classes is two fold. First it requires far more thinking and planning than just spending money. Even here in the States where motorbike racing is not a high priority it is impossible to compete with the factory teams. I don't have the money and no matter how much money one has you can only buy year old race parts because the real new stuff they save for the factory teams. The second reason I like the vintage classes is that it is a trip back to my past the engineering, the people and even the simplistic look of the machinery

I started in auto racing when I was dating a girl who's father was part owner of a BMC dealership He racer Sprites and Midgets. I stopped dating the girl but kept going to the races . I often rode to those races on my Honda 50. Taking back roads. Even then you couldn't ride on the freeways. This was a time when most of my heros both the motorbike racers and the automobile guys ended up being killed. First was Bill Ivy then Eddy Sachs and finally Jimmy Clark by that time I stopped having heros and focused on the machines. So my friend you may have been around for quite a time an I respect your positions and experience this said and because you have brought it up I will only say I received my first competition licence (only a FIA B licence actually) in 1970 . I'll also admit that it has been a terrible waste of a life time by some peoples estimate or standards. For me it has taken me places and let me see things (this even tho I was a only a relative also ran) that have made for a very interesting existence.

Part of the reason I enjoy this forum is on it I see young folks that have the same passion that I have always had. I guess what it is. is a kinship that extends over the years. All my life I've only really had one real lingering fear and that was " I DID NOT WANT TO EVER BE BORED " I haven't been . So as far as I'm concerned " I WIN ! ":)
 

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Or you grind down parts that are too thick and fit lighter, newer parts. Old incandescent headlamps tend to be dull and yellow and suck all the electrons out of a battery and old alternators are not able to replenish supply. I have zero hesitation in changing parts and upgrading them to work better. Some of us have been doing that for years.

We can't necessarily replace thr frame with a chrome moly custom piece, but the spirit of customizing has always been to make the bike into a version that better matches your vision of what it should have been. All bikes are a compromise - performance for comfort, style for functionality and so on. All we do is to try to tip those scales a little in favor of our preferences.

If I can drop 100 pounds off an old bike and add 40-50HP I am a happy chappy. Would that bike ever come close to say a modern sport bike? Not in anyone's dreams, but that's not what I'm trying to do, and I suspect that's true for most of us.

As to rules, in racing it's up to us to interpret those rules to our best advantage. Some have deep pockets and can buy the best. The rest of us just keep stretching the proverbial envelope.
Teazer; Quite so; we have ground off every tiny bracket and tab. If it didn't make the bike run down the lane we took it off. If a fastener was used on an aluminum bit we used a aluminum fastener to screw it down. Everywhere we could we replaced steel nuts and bolts with titanium. Where it is allowed then we resorted to carbon fiber. And yes we replaced the old lead batteries with lithium ones. It has been truly amazing how much weight you can throw in the bin if you are trying and how much difference the lost weight makes. The only example I have of actual weight reduction is out VTR 1000 F that we use as a track and chase bike. I think that motorbike starts life from Honda weighing in at about 194 kg and we got it down to 172 kg. I know doesn't sound like a lot but guys would ride the bike at places like Sears Point or Willows and I'd get the WOW that thing really is fast. "what have you done to the engine ? " LOL the engine is dead stock with 10 K on the poor girl. For the most part throwing weight away and even with the cost of Ti and CF it is the cheap way to go faster. The good news here is that unlike engine messaging this kind of improvement saves the engines,brakes and such rather than over stressing them. Cheers !
 
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