Strom Trooper banner

1 - 10 of 10 Posts

·
Premium Member
Joined
·
658 Posts
Discussion Starter #1
Trying to diagnose a charging problem. Unusual symptoms here. Like there is barely enough to charge. IN 2-13 I had to replace my stater so I upgraded the R/R to the Mosfet at about 30k miles. With no extra load I should get over 14.1 volts. I have l all lights upgraded to LEDS. Anyway I checked the three wires off the stator and get 70 to 76 VAC. Checked the Mosfet FH020AA per Roadstercycles video and it look good. The no load voltage is 15 volts. However one test showed 4 volts at the leads which connect to he battery. Connected the voltage drops to about .2 volts above the battery voltage no mater the battery charge. The battery is 3 years old but get put n a tender one or twice a month. The bike at 63k miles on it now. Any ideas will be helpful. I have the battery charging and will be checking for rubbed wires and good grounds in the morning. It started this at the beginning of a 120 miles trip home Thursday night. Here is a short summary of my pucker trip. I attribute making it home to the LED light.

Coming home the other night I noticed voltmeter connected to the battery dropped from about 14V (GPS & Phone charging) to 12.3 volts. This was unusually and I was thinking my stater (OEM replacement in 2013) was going bad. I had to stop for gas. Inspected the battery connections and tighten them. I disconnected the USB charger for the phones and turned on the GPS connection to reduce the load. Lucky it started. Voltage still low. At 4500 rpm I got 12.8 volts. Above or below and the voltage dropped. Crank the throttle for a hard acceleration, or at least as hard as a 650 can, and the voltage dropped. Ah an Advance Auto. Stopped and borrowed a meter just in case mine was bad. Go out and started up . And 14.5 volts. Mine meter and the borrowed meter. Returned meter, bought a wire brush and cleaned the terminals. Started up and voltage is low. So headed and with fingers crossed. I have LED lights so figured the lower draw was helping. Noticed going though the rough road in Tappahanock Va at constant 4500 rpm the voltage dropped over the bumps. Almost stopped and bought a battery at the Walmart but kept going and made it home.

Thanks

Mike
 

·
Premium Member
Joined
·
658 Posts
Discussion Starter #2
Found the issue. Should have checked the three wires on the stater to ground. All three have 0.5 ohm resistance. I have a spare stater that checks out so will swap that. With the Mosfet and LED lights it could keep up. Good ting I had the volt meter too.
 

·
Registered
Joined
·
788 Posts
Found the issue. Should have checked the three wires on the stater to ground. All three have 0.5 ohm resistance. I have a spare stater that checks out so will swap that. With the Mosfet and LED lights it could keep up. Good ting I had the volt meter too.
That last check is important; it's good that you did it. I do wonder how your spare stator can "check out" when, apparently, it is not yet on the bike. Observing the 70+ RMS open-circuit output voltage at 5000 RPM is also an important check. It shows that there are no shorted turns on the coils.


BTW, your "MOSFET" regulator did nothing special (beyond what a stock shunt regulator would do) to get you home. Depending on how long that trip was and the battery state, the LED headlights may have helped. However, I would recommend, for you or anybody with a failing charging system, that the headlights be unplugged if the sun is up. Even LED headlights constitute the majority of the electrical load, so unplugging them will more than double the bike's run time on whatever battery charge is left.
 

·
Premium Member
Joined
·
658 Posts
Discussion Starter #4
The stator which checked out was the old one. It’s burned. If it get hit it will fail. Ordered a new one. Going to get a series R/R later after it checks out with the new stator (013 instead of old 010). Guess this proves the MOSFET is not the way to go for a Vstrom.

On the current one. It does charge a little. It was dark but I tried to disconnect one headlight. Too tight and hard to pull apart. I did disconnect then today doing some experiments with a fully charged battery. The charging voltage is slowly dropping over time. So I just made it and at least I saved having to get a new battery.

After I get the new stator I need to pick the series R/R. I should be able to spice the three wires. The pickup will be the pain. Then decide on tHe SH775 from Roadster or the Polaris. I don’t need a kit. I should be able to plug it in.

No fake eBay units. 🙂 until next week then.
 

·
Premium Member
Joined
·
658 Posts
Discussion Starter #5
Waiting for the stator from BikeBandit. Ordered it Saturday but 2 day wait. Others were longer. So won’t arrive until next week. I ordered the TRIUMPH - Regulator LINK LEAD, Figured I’d try not cutting the plug on the stator. I already have the super kit installed from when when I got the Mossfet back in 2013. I think I’ll only use the Stator connector part of the link lead keep the DC connected to the battery. Once I get it running I’ll see if I can buy just the SH847 from roadstercycle.
 

·
Premium Member
Joined
·
835 Posts
I'm suspect about the fact that you have 70 VAC on all three leads of your stator but they are also shorted to ground. Something ain't right. You can have the proper voltage or be shorted but not both. When you check for a shorted winding to ground, did you have the stator disconnected? I would also have the battery load tested.
 

·
Registered
Joined
·
788 Posts
I'm suspect about the fact that you have 70 VAC on all three leads of your stator but they are also shorted to ground. Something ain't right. You can have the proper voltage or be shorted but not both. When you check for a shorted winding to ground, did you have the stator disconnected? I would also have the battery load tested.
The stator voltage check has to be done with the 3-wire stator connector unplugged from the regulator. Under that condition, a winding could have a short to chassis without upsetting the voltage reading. (The voltages from each wire to chassis would differ from each other, but the wire-to-wire voltage would be unaffected.) Such a short should be precluded, as the OP (finally) did; if one exists it causes very high currents to flow when the regulator is connected; and such currents will complete destruction of the stator. [a] A "shorted turn" is another matter. That should reduce at least one of the wire-to-wire voltage measurements. But this can be hard to see unless RPM is held very steady.

[a. This is why I earlier said it was good that the short-to-chassis check was done. ]
 

·
Premium Member
Joined
·
658 Posts
Discussion Starter #8
Guess I better report back. Whoops thought I had. So far running well with new and improved OEM stator. The varnish is noticeably thicker then on the two my two old fried stators.

I do want to get a serial R/R in the future. The MOSFET works but reading about it it is not for the DL. It is a shunt type and still dumps to the Stator. But no hurry. I did get the Triumph cable. Used the Stator half so I did not have to cut and splice wires. The R/R end did need to be adjusted to point the correct direction. This requires rewrapping the three wires.
 
1 - 10 of 10 Posts
Top