Your regulator/rectifier burn out?

JoshuaTree · 11-29-2008, 03:22 PM

Test your Stator/Rotor assembly - the (usually yellow) wires, when metered between two of the leads should show some level of AC Voltage (check your repair manual for details on how much and precisely how to at what RPM). There are so many aftermarket R/Rs - I've purchased and used EMGO (generic replacement) on my old EX500 - it ran fine. YMMV...

Just in case you want to understand what's happening on the inside - highly simplified:

This is more likely the case with your bike - a three phase AC stator/rotor combination, and a three phase bridge rectifier:

Homeslice · 11-29-2008, 05:06 PM

Quote:

Originally Posted by JoshuaTree

Test your Stator/Rotor assembly - the (usually yellow) wires, when metered between two of the leads should show some level of AC Voltage

You mean a resistance test? The resistance is normal across the yellow wires.

JoshuaTree · 11-29-2008, 05:44 PM

No - you should also have a voltage reading test. Normally, there should be a reading across any two of "N" wires in a rotor/stator alternator setup (i.e. you're reading a two phase delta - like how 240V is generated out of 120V residential service delivery - two phases in 180 degree opposition generate the voltage delta).

Homeslice · 11-29-2008, 05:59 PM

With the engine running?

JoshuaTree · 11-29-2008, 06:39 PM

Yes. Normally you'll start with a fully charged battery (in your case, you'd use a trickle charger to 'fill up' the battery overnight) - your bike will be running off of the battery for the duration of the test.

You'll disconnect the stator leads at the point closest to the stator before starting. Normally, you'll start the bike and rev it up to the test RPM point - normally between 3000 and 4500 RPM for most bikes (its useful to have help - someone to twist the throttle and someone to take the readings with your multimeter). Test each and every pairing combination - For a 'three wire' system: wires 1&2, 2&3, and 1&3 (or however many pairing combinations to account for the wires coming out of the stator). The voltage should be the same for each of the pairing combinations. Be aware that the plug coming out of the cover may have 'other wires' that are for other sensors/purposes. You'll only need to test the (normally thick) wires for the stator.

Homeslice · 12-01-2008, 12:29 AM

Hmm well the service manual only calls for a voltage reading across the battery terminals. At 5000 rpm it's only putting out 12.5V, which is less than the standing battery voltage of 13.5. So either the stator is fried, or the rectifier is fried. The manual just says to test the resistance across the stator wires, and that's OK so I'm assuming the rectifier is bad.

JoshuaTree · 12-01-2008, 12:35 AM

"Normally" the regulator/rectifier pack is the failure point in most motorcycle charging systems. It is simply reassuring to know if there is a voltage test for the stator/rotor output that would eliminate any doubt about the health of the coils in the stator. A resistance test is fine, but nothing would beat a voltage output check.

At this point, I'd go ahead and get a new R/R pack, and see what you get.

11-29-2008, 03:22 PM	#1
JoshuaTree DILLIGAF? Join Date: Nov 2008 Location: Austin, Texas, USA, Earth, Sol, Western Spiral Arm, Milky Way Moto: 1993 K75SA Posts: 483	Test your Stator/Rotor assembly - the (usually yellow) wires, when metered between two of the leads should show some level of AC Voltage (check your repair manual for details on how much and precisely how to at what RPM). There are so many aftermarket R/Rs - I've purchased and used EMGO (generic replacement) on my old EX500 - it ran fine. YMMV... Just in case you want to understand what's happening on the inside - highly simplified: This is more likely the case with your bike - a three phase AC stator/rotor combination, and a three phase bridge rectifier: __________________ "Quis custodiet ipsos custodes?" "Learn to do the counter-intuitive things that may one day save your ass..." "... Love Much, Laugh Often..." - Amanda Kay Corso (January 18, 1980 - April 15, 2008)

11-29-2008, 05:44 PM	#3
JoshuaTree DILLIGAF? Join Date: Nov 2008 Location: Austin, Texas, USA, Earth, Sol, Western Spiral Arm, Milky Way Moto: 1993 K75SA Posts: 483	No - you should also have a voltage reading test. Normally, there should be a reading across any two of "N" wires in a rotor/stator alternator setup (i.e. you're reading a two phase delta - like how 240V is generated out of 120V residential service delivery - two phases in 180 degree opposition generate the voltage delta). __________________ "Quis custodiet ipsos custodes?" "Learn to do the counter-intuitive things that may one day save your ass..." "... Love Much, Laugh Often..." - Amanda Kay Corso (January 18, 1980 - April 15, 2008)

11-29-2008, 06:39 PM	#5
JoshuaTree DILLIGAF? Join Date: Nov 2008 Location: Austin, Texas, USA, Earth, Sol, Western Spiral Arm, Milky Way Moto: 1993 K75SA Posts: 483	Yes. Normally you'll start with a fully charged battery (in your case, you'd use a trickle charger to 'fill up' the battery overnight) - your bike will be running off of the battery for the duration of the test. You'll disconnect the stator leads at the point closest to the stator before starting. Normally, you'll start the bike and rev it up to the test RPM point - normally between 3000 and 4500 RPM for most bikes (its useful to have help - someone to twist the throttle and someone to take the readings with your multimeter). Test each and every pairing combination - For a 'three wire' system: wires 1&2, 2&3, and 1&3 (or however many pairing combinations to account for the wires coming out of the stator). The voltage should be the same for each of the pairing combinations. Be aware that the plug coming out of the cover may have 'other wires' that are for other sensors/purposes. You'll only need to test the (normally thick) wires for the stator. __________________ "Quis custodiet ipsos custodes?" "Learn to do the counter-intuitive things that may one day save your ass..." "... Love Much, Laugh Often..." - Amanda Kay Corso (January 18, 1980 - April 15, 2008)

12-01-2008, 12:35 AM	#7
JoshuaTree DILLIGAF? Join Date: Nov 2008 Location: Austin, Texas, USA, Earth, Sol, Western Spiral Arm, Milky Way Moto: 1993 K75SA Posts: 483	"Normally" the regulator/rectifier pack is the failure point in most motorcycle charging systems. It is simply reassuring to know if there is a voltage test for the stator/rotor output that would eliminate any doubt about the health of the coils in the stator. A resistance test is fine, but nothing would beat a voltage output check. At this point, I'd go ahead and get a new R/R pack, and see what you get. __________________ "Quis custodiet ipsos custodes?" "Learn to do the counter-intuitive things that may one day save your ass..." "... Love Much, Laugh Often..." - Amanda Kay Corso (January 18, 1980 - April 15, 2008)

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11-29-2008, 05:59 PM	#4
Homeslice Elitist Join Date: Nov 2008 Location: SF Bay Area Moto: Gix 750 Posts: 11,351	With the engine running?

12-01-2008, 12:29 AM	#6
Homeslice Elitist Join Date: Nov 2008 Location: SF Bay Area Moto: Gix 750 Posts: 11,351	Hmm well the service manual only calls for a voltage reading across the battery terminals. At 5000 rpm it's only putting out 12.5V, which is less than the standing battery voltage of 13.5. So either the stator is fried, or the rectifier is fried. The manual just says to test the resistance across the stator wires, and that's OK so I'm assuming the rectifier is bad.