Ok so I went to start my bike after a ride and it wouldnt start. I dont think the battery is being charged while Im riding. The battery voltage is around 12-13 volts when sitting. But when I start the bike the volts drop down to around 11ish volts. If the alternator was working correctly shouldn't the voltage go up to 14-15 volts. Can someone please put some input in. And also, does AutoZone test motorcycle alternators. Thanks guys
Alternator?
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It's very common for the stator and/or regulator to fry on Honda sportsbikes.
Sounds like the stator is toast.
Is the stator connector melted?
Do the workshop manual tests on the stator.
I havent checked. And Im not sure how to test it. It says like I need a amameter or something like that, and all I have is a voltmeter.
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You need a resistance or ohm meter. To measure output you will need a meter that measures AC voltage up to about 70VAC.
If the resistance check fails though you won't need to measure voltage as it indicates the stator is fried.
Gotcha. I dont think autozone can check it, can they. And thanks for the quick responses man.
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I don't know what Autozone is but any mechanic can do the tests if you take the manual with you. Only takes a minute to do.
even if Autozone could check it, would you let them?
You should be able to use your volt meter to see if its the regulator or the stator. find the regulator and probe the hot wires pre and post regulator. If you have 13.5+ volts before, and 11 after... the regulator is bad. If you have 11 volts on both sides, the stator is dying. Make sure to test at a decent engine speed. 2-3K rpm usually works well.
At least this is what we would do with cars that had voltage regulators separate from the alternator.
my bet is it's the regulator...
How old is the battery? Some batteries will stop holding a charge over time rather than all at once, and the symptoms are very similar to a dying stator.
You should be able to use your volt meter to see if its the regulator or the stator. find the regulator and probe the hot wires pre and post regulator. If you have 13.5+ volts before, and 11 after... the regulator is bad. If you have 11 volts on both sides, the stator is dying. Make sure to test at a decent engine speed. 2-3K rpm usually works well.
At least this is what we would do with cars that had voltage regulators separate from the alternator.
my bet is it's the regulator...
How old is the battery? Some batteries will stop holding a charge over time rather than all at once, and the symptoms are very similar to a dying stator.
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The regulator and rectifier are integral so pre-regulator will be AC voltage and not relevant to the post-regulator DC voltage.even if Autozone could check it, would you let them?
You should be able to use your volt meter to see if its the regulator or the stator. find the regulator and probe the hot wires pre and post regulator. If you have 13.5+ volts before, and 11 after... the regulator is bad. If you have 11 volts on both sides, the stator is dying. Make sure to test at a decent engine speed. 2-3K rpm usually works well.
At least this is what we would do with cars that had voltage regulators separate from the alternator.
my bet is it's the regulator...
How old is the battery? Some batteries will stop holding a charge over time rather than all at once, and the symptoms are very similar to a dying stator.
Pre-reg should be in the region of 50-70VAC from memory.
If the voltage across the battery is not rising when the engine is running I would suspect the stator first - assuming everything is connected correctly.
The regulator regulates the voltage _down_ to the required 14.0-15.5VDC so if the voltage is less than that I'd tend to think the regulator isn't getting enough voltage from the stator to need to regulate it. I don't believe a regulator is capable of taking low voltage and increasing it to what is required.
Oh I didnt notice you were from a different country. Ill just take it to a mechanic to have it checked. Thanks again man.
15.5 volts? cars must be different... most sit around 14.4vdc and if it goes higher than that things start to malfunction. You are correct that a regulator regulates voltage down to an acceptable level. I thought that my post implied that, but i may not have been clear. You are right about the AC/DC conversion, i forgot about that.
There is a trick we used to use to see if an alternator was bad. Keep in mind that ive never tried it on a bike, and it can potentially damage the electrical system, but it probably wont. get the bike started and warmed up, get the rpms up to 4K - 5K, and remove the positive cable from the battery. If the bike keeps running the same, the battery is junk. If the bike dies the stator is bad, if it starts running erratically, like rpms jumping, lights flickering etc... its the regulator. if you do try this and it does start running crazy, than kill it as fast as you can. the fluctuation in the current can burn an ECU.
I'm not %100 sure about this trick because even though bikes and cars both run on 12volts, they have very different charging systems. And i have far far far more experience working on cages.
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This might possibly work on older bikes (and of course CDI systems) but I doubt it would work on modern injected bikes. As soon as you disconnect the battery I'd expect the engine to stop due to failure of the injection system. I don't think I've ever tried it myself though.
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Does your trick work on modern injected cars?
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