Coil voltage

[Freak_leg]

I'm trying to cure a hard start issue. I have 13.5v at the battery with ignition off. 10.5v at the battery while cranking, but only 7.5v to 8v at the coil during cranking. This seems low to me. Help. I've only gotten 2 rides in since April. The ridding season in Minnesota is short. I'd like to get in on some of it.

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[93gc40]

Forget the coils for now. At the coils you should have 12v with key on one 1 wire, and interrupted voltage on the other when the motor turns. What are resistances of coils and pulse generators? At the battery what are voltages, OFF, at Idle and at 2500rpm and above? How old is battery and what type? Have you cleaned and lubed the run/stop and starter switches?

[Freak_leg]

Battery voltage at off is 13.5v. Battery replaced last year. Resistance measurements to come

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[93gc40]

Originally Posted by Freak_leg

Battery voltage at off is 13.5v. Battery replaced last year. Resistance measurements to come

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I don't care if the battery was replaced yesterday. It is the #1 suspect till PROVEN otherwise.

[callmeal]

Originally Posted by Freak_leg

Battery voltage at off is 13.5v. Battery replaced last year.

How are you checking the voltage?
To get an accurate check, you should let the battery sit at rest, no charge or discharge, for 30 minutes to let the voltage stabilize. A flooded cell battery should show around 12.65 volts and an AGM should show around 12.71 volts.
A totally dead battery can show as high as 11.9 volts, so you need an accurate voltmeter.
If a battery has been ignored all winter, it can easily go bad in one year. Even an AGM.

[Freak_leg]

I found my voltage drop. Embarrassing really. My improvised ignition switch wasn't letting the coils get enough power. I'll be adding a relay to the set up.

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[Freak_leg]

Originally Posted by callmeal

How are you checking the voltage?
To get an accurate check, you should let the battery sit at rest, no charge or discharge, for 30 minutes to let the voltage stabilize. A flooded cell battery should show around 12.65 volts and an AGM should show around 12.71 volts.
A totally dead battery can show as high as 11.9 volts, so you need an accurate voltmeter.
If a battery has been ignored all winter, it can easily go bad in one year. Even an AGM.

This brings another question. I bring my battery inside for the winter. Will the room temp maintain the battery or should I have it on the tender as if it was outside.

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[callmeal]

Glad you found it.
A dirty engine cut-off switch can do that also.

It’s a good idea to give it a charge several times thru the winter, or at least enough to keep it up to full charge. I don’t leave a tender on them all winter, but many people do.