Tip & How-To about Motorcycles

Rectifier problem

If you suspect that you have a recifier problem ,Borrow or purchase a voltage meter ,Start your bike and put the voltage meter on the positive & negative terminal on the direct current rating ,Rev the bike up slowly to 1000 revs you should be if the regulator is ok be seeing a reading of 13.4 max .Increase the revs to 3000. but only for a few seconds the voltage should stay the same ,Any increase highter that 13.4 then you have a regulator problem .and run the risk of blown fuses or bulbs ,or burnt or melting wiring .One important thing to remember is that your battery must be in good condition..Poor or bad batteries may give a false reading .

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erratic speedometer and odometer when under throttle, just replaced battery because of acid comming out of it, is this a voltage regulator problem

To test the voltage regulator, with a fully charged battery in the bike, use a digital volt ohm meter to check the voltage output of the regulator. Put the meter's function switch in DC VOLTS with a range of 20 volts or higher. Connect the red meter lead to the positive post of the battery and the black meter lead to the negative post of the battery. Start the bike and bring the engine to a high idle. After a minute or so, your meter should read 14.5 to 15 volts. Any higher, you may have a bad regulator.

Good Luck

Aug 05, 2011 | 2000 Harley Davidson FXST Softail Standard

1 Answer

need diagram to diag not charging. thanks

To check your charging system, you'll need a DVOM (digital volt ohm meter). The first thing to do it to take your battery out of the bike and take it to an automotive parts house. Ask them to load test the battery for you. This will ensure that the problem is not the battery.

Now, put the fully charged battery back into the bike. Connect the red meter lead to the positive post and the black meter lead to the negative post of the battery. Put the meter's function switch in "DC VOLTS, 20 VOLT range. Start the bike and bring the engine to a high idle. The meter should read between 14.5 and 15.0 volts.

If it doesn't read this voltage, find the wires coming from the alternator on the lower left front of the engine. Follow the wires back to the round plug and unplug it. Look into the engine side of the plug and you'll see two metal contacts. Make sure these are clean. Put your meter function switch in AC VOLTS, 50 Volt range and start the bike. Bring the engine to a high idle. Put either of the meter probes on one metal contact and the other probe on the other contact. The meter should read 25 volts or higher.

If the battery test reads low but the alternator test reads correct, the regulator is probably defective. If the alternator reads zero voltage or low, the alternator stator is bad.

Good Luck

Aug 27, 2010 | 2000 Harley Davidson XL 1200 S Sportster...

2 Answers

2003 hd ultra classic not charging,how do you test the voltage regulatorr to see if thats the problem ?

With a fully charged battery in the bike, connect a Digital Volt Ohm Meter to the battery, red lead to positive, black lead to negative. Set the meter's range to DC Volts, 20 volts or greater range. Start the bike. The meter should show a rapid build up to between 14.5 and 14.8 volts. If not, check the output of the alternator.

Look down near the oil filter and find the connector on the engine case where your voltage regulator plugs in. Unplug the connector and inspect both ends of it for broken or damaged connectors or wiring inside the plugs. Look down into the connector in the case and you should see two metal connections. This is what we're going to test next.

Put your DVOM meter into AC volts, 50 volts or better range. Make certain your meter is in AC volts as the voltage we'll be testing here is alternating current voltage. Start the bike up and bring it to a fast idle. Put one lead of the meter on each pin in the engine side connector. Since it's AC voltage, it makes no difference which lead goes to which pin. You should be reading at least 30 volts. If so, your regulator is probably bad. If not, your stator is the culprit.

Good Luck

Jul 18, 2010 | 2003 Harley Davidson FLHTCUI Electra Glide...

2 Answers

bike not charging

get access to battery then put meter across it...with bike not running it should read about 12.6v...now start bike and rev to about 3000rpm watch meter it should start to rise up in voltage, maybe to around 13.5v to 14v then quickly regulate back down to 13v...regulator is working o.k. The battery could just have a cell going bad in it and not holding the charge... if still not working, check stator for any open windings...measure any two wires leading into the stator they should all be .1 to 1 ohm .. and if battery is more than three years old... i would suspect that too. if your battery voltage is less than 12v its probably on its way out.

Oct 02, 2009 | 2008 Suzuki GSX-R 600

1 Answer

cagiva solenoid

1. Battery Voltage. - Key off: between 12 - 13VDC.
2. Key off Amp Draw - At the main fuse: < (less than) 1ADC

3. Key on Amp Draw - At the main fuse: Results will vary because of different loads.
*Note - DO NOT START THE BIKE WITH YOUR METER IN PLACE OF THE MAIN FUSE! Also, if you can not access the main fuse, put your positive meter lead on the red wire at the solenoid, and put your negative meter lead on the positive battery lead. This way you will be able to get your amperage readings AND let you start the bike without blowing your fuse.* Charging amperage should be at least 1 ADC

4. Break even speed - The RPM in which the charging voltage at the battery turns positive - Should be before Idle

5. Charging voltage at the battery - Between 13 - 15 VDC.

hope the above details help.thanks for using fixya.

Aug 28, 2009 | 1992 Cagiva Mito 125 - Lawson

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