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F4 Regulator

741 Views 2 Replies 3 Participants Last post by  H2blu-smoke
For the third time in about 4 months, my battery has gone dead. The first time it went dead, I bump started it with no problem. When Metalninjababe was here back at the end of January, it was dead again. This time, it wouldn't even take a charge off a charger, so I replaced it. This morning, in anticipation of riding after the Daytona race tomorrow, I got it out and tried to crank it. It turned over once, then went dead. The guy at the honda place said it was the regulator. sound correct? How much does something like that cost? I have the extended warranty, but I want to see if it was worth getting.

Live fast, die young, and leave a good looking corpse.
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No offense, this isnt meant to sound like a flame but........
If you have the warranty i dont know why you didnt just bring it to the dealer in the first place...why spend your money when you can spend theirs?

Yes it does sound like the regulator. The regulator/rectifier went bad in my F2 last summer. I put in a new battery and it went bad in a week. Then I put in another new battery and let the bike run while checking the voltage at the battery. It read 17.4 VOLTS!!!! No wonder it went bad, the regulator was letting the stator overcharge the battery.

If you want to make sure, put in a new battery and check the voltage with a voltmeter. It should read about 14 volts when running. Slightly less at idle, slightly more at 5000rpms+.
If you need more help, i can look around on my hard drive. I have a .pdf file somewhere on how to check all of that stuff that somebody on esportbike sent me when i was having trouble. BUT if i were you, i'd bring it to the dealer if its covered under warranty.

It cost me $120 from dennis kirk. I think the dealer wants something like $300 for the regulator.

92 CBR 600F2
"95% of Harleys are still on the road today.
5% actually made it home"
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The Honda service manual specifies a current leak specification of 2.0 mA or .002A. This is measured using a DVM or VOM with a current setting (switch setting and appropriate inputs) or a current meter. I use a multifunction DVM.
-Ensure the bike is off.
-Disconnect the negative lead to the battery.
-Connect the negative lead of the meter to the negative terminal of the battery.
-Connect the positive lead of the meter to the negative cable.
-Observe meter reading, it should be 2.0mA or less.
-If you are using an analog meter (type with a needle) the indication may be pegged to the left (infinity) if the leads are reversed. Reverse lead connections if necessary.
As you stated the suspect part could be the regulator/rectifier. To verify this disconnect the regulator assembly (with the battery disconnected) and meter the leakage current as mentioned above. The regulator assembly is located on the left side of the bike under the tail section. A finned assembly. The reason a defective regulator/rectifier assembly can drain a battery is due to one or more of the diodes being shorted. With one of the diode trio shorted (or low omic value) the other two usually supply enough current to charge the battery and run the bike. In the off state(bike turned off) the defective diode(s) discharges the battery over some period of time. A battery that is completely discharged (0 VDC) presents a very low resistance to a charger, meaning it seems not to take a charge. However, if the battery is still good it can take a day or so to fully charge depending on the charge rate (size of charger, setting, etc.). Well now that I have throughly confused and bored you, I wish you luck with your problem. I'm still waiting for warmer weather to go riding. Good Luck!
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