stator/voltage regulator

[Jack Klarich]

One question more, Has this bike been painted recently, reason I ask is these regulators require a good ground or they will fail and not be able to function as a heat shunt either and we all know now how important that is JMO

 

[Hoople]

One question more, Has this bike been painted recently, reason I ask is these regulators require a good ground or they will fail and not be able to function as a heat shunt either and we all know now how important that is JMO

Great point Jack... A small voltage drop would eat regulators alive.:s

 

[89 FXRS]

One question more, Has this bike been painted recently, reason I ask is these regulators require a good ground or they will fail and not be able to function as a heat shunt either and we all know now how important that is JMO

No Jack - the entire bike has stock paint from the frame to the sheet metal - the bike if anything sat for long periods of time, but I wouldn't think it would cause a regulator to go bad would it?

 

[NEWHD74FAN]

No Jack - the entire bike has stock paint from the frame to the sheet metal - the bike if anything sat for long periods of time, but I wouldn't think it would cause a regulator to go bad would it?

Okay, so you checked the Stator output at the plug...what voltage did you read, or where you doing the non-powered DMM resistance check.

Giving us hard numbers will help. What is the charge voltage when at idle and at say 1500 to 2000 RPM? The tale of the tape will be your answers...:s

 

[89 FXRS]

Okay, so you checked the Stator output at the plug...what voltage did you read, or where you doing the non-powered DMM resistance check.

Giving us hard numbers will help. What is the charge voltage when at idle and at say 1500 to 2000 RPM? The tale of the tape will be your answers...:s

NEWHD - the stator output at the plug is 18vac @1000 rpm and 37vac@ 2000
which is within the range according to the fac. manual - the charge voltage across the battery stays the same at any rpm - that's why I think it's the voltage regulator. Some say both the stator and voltage reg. should be replaced at the same time - I'm wondering because both items are not that old and the stator is putting out the correct voltage, and it just started doing this, does it need to be replaced?

 

[brutal]

If your voltage is around 15VDC at any RPM, you have a bad Regulator OR a bad regulator ground. Usually if you have anything above 12 VDC, while bike is running, your charging system is working fine, (so long as it stays under 15)

 

[NEWHD74FAN]

A very common problem is the plug going to the VR oft times contacts lose tension or wires internally break...what is the charge voltage with the VR installed...it should read 13.8-14.2 VDC if the battery is fully charged. If you pulled and load tested the battery using the external Battery Tender harness to charge battery directly on the bench to full float voltage, it should read 12.8 to 14.2 (a higher number is because you just take it off the charger).

Install the battery, aim the headlight at a blank wall...and hit the starter, the headlight if it dims more than 1/4 Brightness to totally going out...your battery surface charge/reserve is insufficient (this is your online battery load tester) once the engine starts (if voltage drops below 9.5V ignition power will be insufficient to start the bike). If voltage stays at 12.6 and starts dropping after running, the charging ckt is not able to keep up, and so I would suspect the VR unit first (it is also the easiest/cheapest to replace. Then I would pull the primary cover and take a whiff...if it smells strong/burn varnish, your charging system is suspect.