Over voltage

highskyflyn · Post by **highskyflyn** » Thu Nov 03, 2011 8:38 pm

So my starter quit in my CA77 the others day and have been kick starting it. Then it died on my one night running the lights. I put a multimeter on the battery and with the key off it reads 13v. The key in the on position(day) 6-7v. The key on(night) 3-4v. After I kick start it jumps up to 15-16v. I replaces the rectifier with one from Oregon cycles and all the wiring, headlight, taillight, all new. Am I dealing with a bad stator? Bad battery? I'm lost on what to do next.

Snakeoil · Post by **Snakeoil** » Fri Nov 04, 2011 10:13 am

I think this is just how they work. They are unregulated systems to the faster the engine spins the higher the voltage. I suspect the battery is the regulator.

I posted a similar situation, only my battery was the indicator by being very low in electrolyte. No leaks means it boiled off.

My guess is you could probably regulate the system by adding a regulator, but the losses would be such that the weak system would now be weaker yet.

I need to put a DMM on my system, but the bike is put up for the winter so maybe in the spring.

regards,
Rob

highskyflyn · Post by **highskyflyn** » Sat Nov 05, 2011 6:54 am

The only thing is that I can't use my starter because when I turn the key the voltage is too low to even energize the relay and kick over the electric starter. I'm thinking I fried the battery along the way of finding this problem and im going to try a new battery. Here's hoping its not the stator :/

G-Man · Post by **G-Man** » Sat Nov 05, 2011 8:25 am

Check the connections to the battery. As Snakeoil said, the batter forms part of the regulation. So, if the connections to the battery or the batter itself goes bad, the voltage will be higher because the resistance in the circuit is higher.

The low voltages you are seeing when operating the stater suggest that you need a new battery.

G

highskyflyn · Post by **highskyflyn** » Sat Nov 12, 2011 1:41 pm

alright so I bought a new battery and have been running it for a week now. I bought a serviceable battery, filled it and charged it as the battery's manual recommended. At the battery posts the system reads a constant 15 volts +/- 1 volt with lights on and off. Its now day 6 and the voltage reads 15.4 and when I press the starter button its acts as if the battery is dying. the voltmeter drops to 6 volts when starter button pressed and the starter is beginning to be very sluggish. Im a pilot and always at the airport and was talking to an aviation mechanic and he says that a 12 volt system thats running more that 13 volts at the battery will eventually fry the battery. I believe this is what happened to my last battery because it was brand new also. SO I believe that I'm possibly running a bad stator thats running too much voltage and killing my battery. Does anyone have any suggestions on what I should do next? Do anyone agree that its the stator to blame?

Snakeoil · Post by **Snakeoil** » Sat Nov 12, 2011 5:54 pm

The British bikes regulated their unregulated system by using a zener diode that would fire at some set voltage, probably 13 volts or so. It would dissipate the charging current by taking it to ground.

They got hot and failed, but they also worked. It's a crude system but simple.

You could probably rig up a similar system on a Honda.

I guess the real question here is what is causing his system to fry his battery. My CL77 does not have an electric starter so whether or not the battery will take a load by itself is never really tested since it is kick start only.

HSF, does your electrolyte level go down? I would expect it to if you were overcharging the battery.

G-man is the expert here. I'm decent with electrics, but I'm no expert on charging systems. I cannot figure out why a known marginal charging system would over-charge a battery.

regards,
Rob

highskyflyn · Post by **highskyflyn** » Sat Nov 12, 2011 6:57 pm

the electrolyte keeps the same level the entire time. After losing my first new battery and replacing it I have been riding it everyday and watching the voltage everyday to keep notes on what the system is doing.

Im lost at what to do because this is a renovated project and the only thing thats not new in the entire electrical system is the coil, condenser, points, and the stator. For the system to be overcharging and frying the battery it either the stator or a wiring grounding out somewhere.

I spent a couple of days tracking every wire down and making sure theres nothing grounding out which leads to believe that its the stator creating too much voltage. The only thing is that theres no regulator to regulate the voltage from the stator which is sending too much power to the battery.

Im no electrician and really pretty young at understanding an old way of using electrically but the voltage numbers just don't add up.