About 5 weeks ago I went for a ride over to my brother's house. When I tried to leave, the bike wouldn't turn over. It just made a clicking sound. I push started it, and made it home. The next day I bought a new battery and things have been working great. Last weekend after riding for about 2 hours, we stopped for a beer and when we tried to leave the bike wouldn't start. Same thing, it just clicked. Do I need to replace my alternator or voltage regulator? It seems that everyone that I know (none of them very bright, unless they are drunk) have a different opinion. Any help is appreciated.
Thanks
Inferno00

 

Well, I don't drink but I would like help if I can. I am a veteran of one charging system failure on my RK. You didn't say what bike/year you had but I'm sure it's a Harley. Assuming your battery is OK I would first charge it up. You may want to have it tested before you continue. Start your engine and with a reliable volt meter connected across your battery rev up the engine. You should see around 14 volts on the meter. You might even want to let it run like that for 5 or 10 minutes because there is a situation where it may charge when cold only and then quit.

If all looks well you may have something draining the battery while you're not riding it. There are ways to check for a drain.

If the charging voltage is not around 14 volts you will need to determine if the stator and regulator are working. Generally, to test a stator you will need a voltmeter that reads a.c. volts. Disconnect the stator and connect the meter to the two wires that come out of the motor. Start the engine and rev the motor a bit. You should see 50 - 60 volts a.c. at a high idle. If you do, then your stator is working but keep in mind that a bad stator might work for a few minutes when cold and then quit. (That's what mine did - it would work for about 10 minutes)

The regulator is pretty simple to test: If there is good a.c. input to it from the stator then it should supply about 14 volts d.c. to the battery. If not, the regulator may be bad. Some bikes have trouble with the wires shorting out around the regulator bracket. Check that over closely before getting a new regulator. Of course check all your connections thoroughly.

If it turns out there is no output from the stator you will need a new one. Don't assume the regulator is bad though until you are sure there is output from the stator . The regulator can't damage the stator so don't assume they are both bad. (Mine has been working fine to this day - well, as fine as a H-D charging system can be that is). The regulator doesn't control the output of the stator like on a car or other bikes. Engine speed controls the output of the stator and there are a lot of stator failures.

Hope this helps.