Is my bike putting out the volts it needs?

I just put a new battery in my bike because the old one was toast. I noticed an alternater wire at the rectifier, and the ground to the zener diode where not hooked up which I'm guessisg why my batteries have gone bad so fast. I did the test from the manual hooking the volt meter negitive to the center rectifier terminal and and postivie to ground. I reved to 3k RPM and got 14.6 or so with the key in the first position with no lights. With lights on i'm getting 13.5 or so at 3k RPM. The book doesn't say to test with lights on or not so I'm just wondering if those numbers sound about right. I unhooked the zener and did the same test at 3k RPM and got 16.4. I'm not sure if the voltage should get much higher with zener unhooked or not. Rectifier lead may need a little cleaning which might help. I'm dumb with elctrical so I'll have pletty more questons in the future i'm sure.

Those numbers sound about right to me. The zener will keep the battery from overcharging, like the 16 volts you are getting. You really don't want to charge a battery much more than 14.6V, especially continuously, but if you're riding and have any lights on, it probably won't get that high.

Dave
69S

Wadep77 said:

I unhooked the zener and did the same test at 3k RPM and got 16.4. I'm not sure if the voltage should get much higher with zener unhooked or not.

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The Zener is the voltage regulator so it seems to be doing its job.

Avoid running with the Zener disconnected, if the voltage is allowed to rise over 16V it can damage electronic ignition, if fitted.

I do have a boyer electronic ignitoin. I hope I didn't mess anything up with he zener unhooked all last season. The bike still starts right up in a kick or 2 so I think all is well. I just now started reading up on all the electrical so I have a little better ideal about how it works. Thanks for the input.