'08 SMR510 Charging System Problems

My 08 smr510 is having charging issues. I am having trouble keeping my battery charged. I keep my battery charged with a Battery Tender when not riding, and it maintains the battery at about 13.3 volts. When it is running, I only see about 12.5VDC at idle and about 12.6VDC at the battery at about 4000 RPM. I have a new battery and I replaced the voltage rectifier/regulator, but I still see no more than 12.5 – 12.6VDC when running.

Measuring the stator output I get the following at idle:
A>B ~33VAC
A>C ~33VAC
B>C ~33VAC

Measuring the stator output at 4000RPM I get the following:
A>B ~55VAC
A>C ~55VAC
B>C ~55VAC

Measuring each stator output to ground I get the following at idle:
A>GROUND ~ 23VAC
B>GROUND ~ 7VAC
C>GROUND ~ 23VAC

Measuring each stator output to ground at 4000 RPM I get the following:
A>GROUND ~ 55VAC
B>GROUND ~ 14VAC
C>GROUND ~ 55VAC

It seems odd that one leg measured to ground is so much lower than the other two, but I don’t know what it is supposed to be. Does anyone have any experience with these charging systems? I would expect the charging voltage to be around 13.5 – 14VDC when running. Has anyone checked theirs and know what it should be?

Thanks in advance for the help, and sorry for the long post.

According to the manual, your 12.6V measurement at the battery is right at the low end of the spec', however, I've never seen a charging system that charges that low. I just checked mine, and at idle it's 14.56VDC with .2v of AC ripple. This is more of what I would expect to see.

The odd 7V leg on the stator does not seem right. Something is causing that low voltage. The check for the stator involves measuring resistance between the leads. See the procedure below. If that looks right, I would bet $$ that it's the voltage regulator. Unfortunately the VR check is to swap it out and recheck the resistances. Oddly, the voltage that they expect in this check is 14V. Before buying another VR, I'd make sure the connector at the VR is clean and seated properly.

BTW, what did you use for test-points in the initial voltage measurements of 33V & 55V?


1) EXCITER - Resistance between BLACK-RED and RED-WHITE cables:
12,7 +/- 15% (TC-TXC-SMR 450-R)
1) TRIGGER - Resistance between WHITE and GREEN cables:
100 +/- 15% (TE-SMR)
2) CHARGE- Resistance between YELLOW and WHITE cables:
0,16 +/- 15% (TC-TXC-SMR 450-R)
2) CHARGE- Resistance between then YELLOW cables:
0,65 +/- 15% (TE-SMR)
3) LAMP- Resistance between YELLOW and GROUND cables on the engine:
0,65 +/- 15% (TC-TXC-SMR 450-R)



Voltage regulator-rectifier checking (TE-SMR-TXC-SMR 450 R)
With the ignition definitely functional, whilst the battery is charged (12.5V-13V),
start the engine: if the battery tension does not increase (14 V) after about two
minutes, substitute the regulator. To access the regulator, remove the seat and
fuel tank (pages E.15, E.23). Remove the fixing screw (1) and the regulator.

Thanks for the reply. The 33v and 55v stator measurements were taken via the plug underneath the tank. I loosened and propped the tank up some so I could sorta get to stuff under there, unplugged the stator leads (big round black plug under tank with the 3 yellow leads in it) and started the bike. I then read between each of the three leads and then read each lead to ground. Your 14.5v reading at the battery sounds right. I have replaced the VR and it made absolutely no difference- I still only see about 12.6-12.7VDC at the battery while running. The longer the engine runs, the weaker the battery gets. All connections are as clean as the day the bike left the factory. I guess the only thing really left is the stator coil- I don't know if the voltages I am reading are good, bad, or what. I am afraid to find out what that costs.

Below is the procedure for testing the stator. Good luck. Some of these parts are stupid expensive.

1) EXCITER - Resistance between BLACK-RED and RED-WHITE cables:
12,7 +/- 15% (TC-TXC-SMR 450-R)
1) TRIGGER - Resistance between WHITE and GREEN cables:
100 +/- 15% (TE-SMR)
2) CHARGE- Resistance between YELLOW and WHITE cables:
0,16 +/- 15% (TC-TXC-SMR 450-R)
2) CHARGE- Resistance between then YELLOW cables:
0,65 +/- 15% (TE-SMR)
3) LAMP- Resistance between YELLOW and GROUND cables on the engine:
0,65 +/- 15% (TC-TXC-SMR 450-R)
If the resistance is not between the specified values, replace the generator assy.

Cetris...did you ever resolve your charging issue? I have the exact same bike and I'm having the exact same issue...although my voltage is a bit lower at 12.3VDC - 12.42VDC. I too have replaced the Voltage Regulator (like everyone keeps saying to do) but the problem still exists.

I've checked the resistance on....

2) CHARGE- Resistance between then YELLOW cables:
0,65 +/- 15% (TE-SMR)

and got a read of 0,3 ohms.

This is where I'm at to date with the issue when I read your earlier posts - so any tips on your lessons learned would be appreciated.

Thanks!

I had nearly identical numbers. It ended up being the stator coil. It is at about 15 V idling now. No more issues.