Have you checked that the front and rear brakes actually turn the brake light on and off ??
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I'm totally confused here. I need some help.
- Thread starter cmyoch
- Start date
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- Tags
- electrical
cmyoch
XS650 Junkie
Front brake switch works fine. Rear switch never worked but I never had any problem until now.
cmyoch
XS650 Junkie
So I reviewed Curly's guide and this is what I have so far.
New brushes to start off
5.9 ohm between slip rings
Grounded the regulator, no change in voltage at 3,000 plus rpms
AC test on all 3 rectifire (white ) wires. NOTHING. Nothing registered at all. I'm thinking that my head light short finally took the rectifier out. Just to clarify, I set my meter to AC, ran the bike at idle, touched positive to each connector, and touch the negative probe to the frame. I'm hoping this is the problem. Thoughts?
New brushes to start off
5.9 ohm between slip rings
Grounded the regulator, no change in voltage at 3,000 plus rpms
AC test on all 3 rectifire (white ) wires. NOTHING. Nothing registered at all. I'm thinking that my head light short finally took the rectifier out. Just to clarify, I set my meter to AC, ran the bike at idle, touched positive to each connector, and touch the negative probe to the frame. I'm hoping this is the problem. Thoughts?
Were the whites still connected between the stator and the rectifier? With the connector apart there is an ohm spec for the stator wires.
cmyoch
XS650 Junkie
Yes they were all connected. I just realized that I did my regulator test without the plug connected. I grounded the green wire as the instructions state and I keep blowing my main fuse.
cmyoch;
From your last few posts, there are a few errors in your testing.
When testing for AC voltage at the 3 white stator wires. The meter leads are connected to the white leads only..................you do not connect one meter lead to ground. There are 3 combinations to test, when measuring from white lead to white lead. This is 3 phase AC power with no reference to ground. Connector must be connected and engine idling..................should measure around 12.5 to 13 volts AC.
Curly's guide says to ground the green lead for the solid state regulator which is for the 80to 83 years. But your bike being a 78 did not have the solid state reg. That's why you blew the fuse...............you're putting a direct short on your regulator output.
When you had the brushes out and measured resistance from slip ring to slip ring, you should also have measured from either slip ring to the rotor steel frame using a high ohm scale..................did you do that?
From your last few posts, there are a few errors in your testing.
When testing for AC voltage at the 3 white stator wires. The meter leads are connected to the white leads only..................you do not connect one meter lead to ground. There are 3 combinations to test, when measuring from white lead to white lead. This is 3 phase AC power with no reference to ground. Connector must be connected and engine idling..................should measure around 12.5 to 13 volts AC.
Curly's guide says to ground the green lead for the solid state regulator which is for the 80to 83 years. But your bike being a 78 did not have the solid state reg. That's why you blew the fuse...............you're putting a direct short on your regulator output.
When you had the brushes out and measured resistance from slip ring to slip ring, you should also have measured from either slip ring to the rotor steel frame using a high ohm scale..................did you do that?
cmyoch
XS650 Junkie
No wonder I'm thinking my charging system is all jacked up! That's why I rely on you guys so much! I now know how to correctly test my rectifier. Since I do not have a solid state regulator, how do I test mine? I'm not getting any magnetic field when I touch my feeler gauge to the case when I turn the key. I have a home made rectifier on the shelf, I may just go ahead and put it on. I may go ahead with the automotive regulator too.
Regulator by-pass for your 78.
Unplug the voltage regulator.
Use a jumper wire directly from the battery positive ( a 10 amp in line fuse is not a bad idea). With engine running, touch the jumper wire to the left (outer) brush which is the green wire. Have your VOM reading the battery voltage. Rev the engine and see if the battery voltage increases. Don't let the voltage go above 15 volts.
If the battery voltage does increase as you rev the motor, then that proves the regulator is defective.
A new rectifier with heat sink, and a new solid state automotive regulator are one of the best things you can do for these bikes.
Unplug the voltage regulator.
Use a jumper wire directly from the battery positive ( a 10 amp in line fuse is not a bad idea). With engine running, touch the jumper wire to the left (outer) brush which is the green wire. Have your VOM reading the battery voltage. Rev the engine and see if the battery voltage increases. Don't let the voltage go above 15 volts.
If the battery voltage does increase as you rev the motor, then that proves the regulator is defective.
A new rectifier with heat sink, and a new solid state automotive regulator are one of the best things you can do for these bikes.
cmyoch
XS650 Junkie
I'll pick up another in line fuse today and wire it up for the test. I'll hook it to the outer brush and run my test. I will also test my stator correctly and post my findings. Surely the short in the head light didn't short out the windings in my stator?
I did notice a month ago while riding at night that my head light would periodically dim but would brighten back up after a bit. So this being the case, maybe this short pushed whatever it was that was going out over the edge.
I did notice a month ago while riding at night that my head light would periodically dim but would brighten back up after a bit. So this being the case, maybe this short pushed whatever it was that was going out over the edge.
cmyoch
XS650 Junkie
Ok. I haven't touched the bike in a few weeks due to other projects around the house. I've made my own rectifier and did the bypass test as suggested. I fired it up just now and there is still now change in my voltage at the battery. I still need to test my newly built rectifier. I assumed it was functioning properly. RG, you mentioned testing from slip ring to the rotor frame. What ohm reading am I supposed to get there? I sure hope I'm not dealing with a rotor issue here.
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cmyoch
XS650 Junkie
Dumb question, do I need to pull the side case cover to access the stator wires for testing??
cmyoch;
Forget about the stator for now. You said there was no magnetic field from the rotor. At this point, we need to establish why there is no magnetic field from the rotor.
Try the feeler gauge test once again. Regulator plugged into harness. Remove the small round cover from the alternator. Hold a 0.003" feeler gauge 3/4" away from the large nut on the crankshaft. Turn on the key. Does the feeler gauge pull over to the nut?
Remove both brushes, and measure resistance (using the highest ohm scale) from either slip ring to the rotor frame. Should measure infinity..............i.e. open circuit.
Forget about the stator for now. You said there was no magnetic field from the rotor. At this point, we need to establish why there is no magnetic field from the rotor.
Try the feeler gauge test once again. Regulator plugged into harness. Remove the small round cover from the alternator. Hold a 0.003" feeler gauge 3/4" away from the large nut on the crankshaft. Turn on the key. Does the feeler gauge pull over to the nut?
Remove both brushes, and measure resistance (using the highest ohm scale) from either slip ring to the rotor frame. Should measure infinity..............i.e. open circuit.
From cmyoch;
"I didn't have a .003 feeler gauge. My lowest one is
.008 but it did stick to the crankshaft nut when I turned on the key. So that means I have power through the rotor right? Now it wasn't enough to draw a feeler gauge with the cover on but at least there is something there. I tested my resistance between rings and I'm around 5 ohms on the 200 setting on my meter. When I test each ring to the rotor housing, I get no reading at all. It stays the same as if I didn't touch the two probes together. That means an open circuit right? "
"By the way, I just tested my power to the positive brush again and my readings were 12.09 at the battery (With the key on) and 11.84 at the positive brush. I know the voltage at the battery is getting low. I had my charger hooked up to my car this evening so I relied solely on what juice was left in the battery. I unplugged my rectifier and tested the resistance on all 3 white wires. I was consistant at infinity with the recitfier unplugged. I think I read that this test is done with the white wires from the rectifier unplugged."
Your testing is starting to wander, so lets move on.
OK, now its time to measure stator output voltage.............this will be AC volts not DC volts. This is done with everything plugged in and the engine idling at 1200 rpm. Measure at the connector that comes up from the alternator (next to the battery). There are 3 white wires. Put your meter probes into the back of the connector. Measure from one white wire to another white wire. There are 3 different combinations of white wires. What AC voltage do you measure on the 3 combinations?
"I didn't have a .003 feeler gauge. My lowest one is
.008 but it did stick to the crankshaft nut when I turned on the key. So that means I have power through the rotor right? Now it wasn't enough to draw a feeler gauge with the cover on but at least there is something there. I tested my resistance between rings and I'm around 5 ohms on the 200 setting on my meter. When I test each ring to the rotor housing, I get no reading at all. It stays the same as if I didn't touch the two probes together. That means an open circuit right? "
"By the way, I just tested my power to the positive brush again and my readings were 12.09 at the battery (With the key on) and 11.84 at the positive brush. I know the voltage at the battery is getting low. I had my charger hooked up to my car this evening so I relied solely on what juice was left in the battery. I unplugged my rectifier and tested the resistance on all 3 white wires. I was consistant at infinity with the recitfier unplugged. I think I read that this test is done with the white wires from the rectifier unplugged."
Your testing is starting to wander, so lets move on.
OK, now its time to measure stator output voltage.............this will be AC volts not DC volts. This is done with everything plugged in and the engine idling at 1200 rpm. Measure at the connector that comes up from the alternator (next to the battery). There are 3 white wires. Put your meter probes into the back of the connector. Measure from one white wire to another white wire. There are 3 different combinations of white wires. What AC voltage do you measure on the 3 combinations?
cmyoch
XS650 Junkie
I'm not getting any voltage reading at all whatsoever. I have it set to AC voltage. I also took the probes and touched it to the wires on the brushes. I didn't get any reading there at all either.
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cmyoch
XS650 Junkie
It's been a while since I touched the bike. I bought a used rotor and stator from blackbetty here on the forum. As I prepared to disassemble my bike for the replacement parts, I ran a resistance test on both my parts and his. Turns out, I get almost the same reading on both rotors (5 ohms on mine and 5.2 on his) and the same resistance reading from the white wires to the stator (1.2 ohms all around on both parts) My rotor is magnetic when I power it. What should I test next?
You better redo these tests..................I don't think you can measure zero voltage.
Just turn the key on.................what DC voltage do you measure on the brush terminals?
The AC voltage is done with the engine idling and connectors connected.
cmyoch
XS650 Junkie
I'll re-assemble the whole system and put the tank back on hopefully tomorrow. I remember in a prior test that I had 12.3v at the battery and 11.9 or so at the positive brush on my last test but I don't remember if I had the bike running or not. I'll do the test and report back.
Part of me wants to install the new rotor and stator I recieved today and do the mod regulator. I built my own rectifier so between these, I would hope to have fixed the problem. Then again with my luck, I'd do all this and there still be an issue.
Part of me wants to install the new rotor and stator I recieved today and do the mod regulator. I built my own rectifier so between these, I would hope to have fixed the problem. Then again with my luck, I'd do all this and there still be an issue.
cmyoch
XS650 Junkie
Today I installed blackbetty's rotor and stator off of his '75. I also installed my home made rectifier and a VR115 regulator. She is charging again! I noticed when I popped the old rotor off that the PO torqued the rotor down without having the key hole properly aligned. Now when I fire her up she dies at idle which leads me to believe I am slightly out of time. Now I need to research how to properly set the timing. This will be tricky since I have contantly hold the throttle open a bit to keep it running while I check the timing. This is going to be tricky.
I'll postpone this until tomorrow when I have more patience!
I'll postpone this until tomorrow when I have more patience!
1974jh5
Curmudgeon.
Watch for cheapie bulbs, too. My (happily now ex-) wife's 1986 Accord continually had goofy taillight messages in the vehicle information display until I put in good quality name brand bulbs.
Assuming points, static time it with a light bulb before you go to the timing light.
