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Discussion Starter · #1 ·
1985 Nighthawk 450CC. Battery replaced last October... iffy. Got one "at cost" from a friend who put it in, but the bike ran all winter.

Wouldn't start in June. Had to connect my 2V charger. Started, ran fine. Then, the end of July, I drove it 7 miles. Stopped for gas. Wouldn't start. Got it charged. Fine for 2 weeks. Now, I have to basically charge it almost every day. Bad battery or expen$ive alternator? I'm afraid to stop and get gas now! (Can I fill the tank w/ the engine running?)

Do shops/Napa (closest parts store) charge a lot to check the battery/alternator? Money is so damned tight (or I would have a shiny new bike). Halp!
Thanks.
 

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Happy Rider
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Many auto parts stores will check your battery for free. I don't know if it the case with your model but some of that vintage need to have the RPMs up around 2500-3000 to charge the battery.
 

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Save them all!
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Do you have a multimeter anywhere? It's pretty easy to check your voltage and your charging system.
 

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If I had to take a wild guess I would say your charging system wasn't putting enough voltage out. You've replaced the battery pretty recently, so odds are that's good (unless it's gone south from being depleted so often.)

Check that both of the battery connections are clean, as well as any grounds on the bike. You can also find and check the plastic plug connectors from the stator and going to the regulator and look for dirty/melted connections. (Particularly the stator plug - which is somewhat possible.) It may be as simple as cleaning a connection, or replacing/soldering them if a plug has melted.

Just a guess though. As said above, do have your battery tested.
 

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Discussion Starter · #7 ·
If I had to take a wild guess I would say your charging system wasn't putting enough voltage out. You've replaced the battery pretty recently, so odds are that's good (unless it's gone south from being depleted so often.)

Check that both of the battery connections are clean, as well as any grounds on the bike. You can also find and check the plastic plug connectors from the stator and going to the regulator and look for dirty/melted connections. (Particularly the stator plug - which is somewhat possible.) It may be as simple as cleaning a connection, or replacing/soldering them if a plug has melted.

Just a guess though. As said above, do have your battery tested.
I appreciate your quick response. I should have added that I am in NO way a mechanic. I know more about the central nervous system than car/motorcycle engines.
 

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I concur with the above, always good to check and keep clean regardless but could very well be the problem. If melted I would be curious on the cause.
The stator plugs melt on some Honda bikes of that era. I'm not sure if they just weren't heavy enough or what, but I just solder the connection anytime I work on one.
 

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I appreciate your quick response. I should have added that I am in NO way a mechanic. I know more about the central nervous system than car/motorcycle engines.
Look around for a service manual. It's worth its weight in gold! (Might even find some good resources online!)
 
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