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mshick68
XS650 Addict
5 twins, I did cut them back and re installed. Fired up so I took it for a ride. about 15 minutes nto the ride it cut off again. Geez I thought I had it. Driving me nuts. Grinder I have not. So just hook the volt meter to the battery and keep it reved a little? i dont have a tach. Let me give it a try
mshick68
XS650 Addict
k just tried it. 12.4 volts when Im reviving but could that be because I have beat up the battery today or once it fires it should be charging at 14volts regardless??
At idle, it should be somewhere around 12, when revved, it should go up to somewhere between 13.5 and 14.5. If you get no change (rise), you're not charging. The ignition will start acting up once the battery starts to get low. These bikes need a good, nearly fully charged battery to run the ignition and to run right.
mshick68
XS650 Addict
OK so I have checked all the wiring for the charging harness including grounds etc... Im using the tcbrothers harness. The bike was running fine two days ago but all wiring looks good. Intresting when the bike was running I checked the brown wire on the rectifier and it was reading 11.40. The red wire on the same plug was reading 12.70. could it be the rectifier
john650
retired mathsteacher..yay
You have to be careful about measuring with a voltmeter, as some of the wires will be conducting pulsed current, which ordinary voltmeters will mis-read. You could have a faulty reg/rec if you are not seeing around 14V dc at the battery terminals when the engine is revved. But if you are not recharging the battery from a domestic charger after each test, I would expect you to have a problem even starting the bike soon.
You could prove/disprove charging problems by just hooking another battery up in parallel. If this improves your running time, then charging circuit is suspect.
mshick68
XS650 Addict
OK thanks. I did hold a small metal washer up to the round left side cover and when I turned the switch it did not pull towards the cover.
mshick68
XS650 Addict
Yikes, what next. Maybe I will follow Currley steps. Help. One note when I re mounted the reg/rec I mounted it on a plastic Elictricsl box used to hide the wires. Does it have to be mounted to metal. Thanks!
mshick68
XS650 Addict
So another test at lunch today. I did the slap test and the wrenc I used did pull to the case. So I jumped the green wire coming from the reg plug to a good ground, reved the bike but only got to 13.4 volts not matter how high I reved it. Now what... What do you guys think?
Follow the charging guide. Measure the resistance from one slip ring to the other slip ring.
A rec/reg does not have to mounted to metal frame.
mshick68
XS650 Addict
sorry where is the slip ring and how do I measure resistance.
The copper rings on the rotor that the brushes ride on.
There is a picture in my album.
There is a picture in my album.
mshick68
XS650 Addict
got it. Can I test without taking the stator off the bike?
Yes, just remove both brushes, then measure the resistance (use the lowest ohms scale on your meter). Note what the meter measures when the 2 meter leads are connected together. That reading is subtracted from what you measure across the 2 copper rings.
Also measure resistance from either copper ring to the rotor steel frame. Use a high ohms scale.
Also measure resistance from either copper ring to the rotor steel frame. Use a high ohms scale.
mshick68
XS650 Addict
OK will give it a try. So what does it tell you that when I rev the motor I only get 12.8 volts. Then when I jumped the green wire from the reg/rec to ground and rev it I only get 13.5. Is it charging? Also it passed the slap test. BTW I,m not using a key switch I;m using a turn style switch. I just wanted to pass that info along. Thanks
Sounds like you are getting only partial charging, that's why you need to measure the rotor resistance. Sometimes the rotor windings are partially shorted out.
The brown wire is the load side of the ignition switch, and the red wire is the supply side (battery side) of the ignition switch. The fact that you measure 1.3 volts drop across the ignition switch, means you have a larger than normal current flow through the switch and/or the ignition switch has a higher than normal resistance.
What do you mean by a "turn style" switch? Is it new or is it old?
Lets see what you get when you measure the alternator rotor resistance.
mshick68
XS650 Addict
OK so I tested the resistance at the rings with ignition off. Got 4.7. There was .3 res at the probs so the final number was 4.4. When I tested the res between the ring and the case I did set the meter to the highest rating which I think was 200k. I got 000 reading. I tried a couple of the upper scales and always got 000 reading. With switch on I measured the top brush and got 11.8 volts but the battery voltage was 12.5. The bottom brush was 0 volts. Also here are pics of the switch I;m using for ignitiion. What do you think? Also I took my battery to advanced just to check it. I bought it in December. Tested fine. They kept it overnight and will run a more in depth test today but I'm pretty sure its good.
Attachments
Sounds like a bad rotor to me. That jives with your original problem too. The TCI ignition is rather fussy about good voltage and will cut out when the battery goes down. How long are your brushes? Getting an accurate reading at 5 to 6 ohms with a cheap meter is unlikely at best. Even with a good meter I see some big variation on readings.
I would throw a digital volt meter on it and watch what happens when you are running it. It should hold roughly 13.5 at any speed above idle. It's possible you just have a weak timing magnet on the rotor. What battery are you running? Poor grounds and trashed batteries can throw off any efforts at trouble shooting.
So it seems likely you either need a rotor or you'll have to replace the entire charging system and ignition with a PMA Pamco set up. You will need to get a TCI rotor with the magnet to fire your TCI ignition. Be leery of "new" rotors, as the thickness isn't always right which causes ignition problems that will drive you loco. A quality rewind is probably the best option. Or find a "tested good" used rotor and keep your fingers crossed. Buy a rotor puller or try to track down the loaner puller that circulates on here.
I would throw a digital volt meter on it and watch what happens when you are running it. It should hold roughly 13.5 at any speed above idle. It's possible you just have a weak timing magnet on the rotor. What battery are you running? Poor grounds and trashed batteries can throw off any efforts at trouble shooting.
PS I have been following the thread, I think you have been getting good advice, Electrical trouble shooting mainly involves slow accurate testing and eliminating variables. You are getting there.
I would throw a digital volt meter on it and watch what happens when you are running it. It should hold roughly 13.5 at any speed above idle. It's possible you just have a weak timing magnet on the rotor. What battery are you running? Poor grounds and trashed batteries can throw off any efforts at trouble shooting.
So it seems likely you either need a rotor or you'll have to replace the entire charging system and ignition with a PMA Pamco set up. You will need to get a TCI rotor with the magnet to fire your TCI ignition. Be leery of "new" rotors, as the thickness isn't always right which causes ignition problems that will drive you loco. A quality rewind is probably the best option. Or find a "tested good" used rotor and keep your fingers crossed. Buy a rotor puller or try to track down the loaner puller that circulates on here.
I would throw a digital volt meter on it and watch what happens when you are running it. It should hold roughly 13.5 at any speed above idle. It's possible you just have a weak timing magnet on the rotor. What battery are you running? Poor grounds and trashed batteries can throw off any efforts at trouble shooting.
PS I have been following the thread, I think you have been getting good advice, Electrical trouble shooting mainly involves slow accurate testing and eliminating variables. You are getting there.
That 4.4 ohms falls outside the acceptable range for the rotor windings. If you are reading 0 ohms from one slip ring to the rotor/stator frame, then that is bad.
Just to be sure, try measuring again from either slip ring to rotor/stator frame (both brushes removed), using some lower scales such as 200 ohms and 1 k ohms.
That "turn style" switch looks suspect. I would not use that. Buy yourself a proper motorcycle ignition switch.
Just to be sure, try measuring again from either slip ring to rotor/stator frame (both brushes removed), using some lower scales such as 200 ohms and 1 k ohms.
That "turn style" switch looks suspect. I would not use that. Buy yourself a proper motorcycle ignition switch.
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