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Discussion Starter #1
Pretty sure it's electrical but I'm in over my head. Took the bike for a ride up north - was going up a hill and felt the engine kinda spluttering (like I was running out of gas, which I wasn't), and then noticed that the speedometer and digital trip meter was dead as a door nail - after a while it flickered back into life, but died again.

Got almost home, engine sounded ok but speedo was dead - 5 mins from home and the engine stalled, complete electrical failure and couldn't get it to start. No lights, no horn, no nothing. Pushed it home, where the bike now sits, beaten but not defeated.

Any ideas? Where do I start in order to get my machine back on the road?

Many thanks!

- J
 

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Pretty sure it's electrical but I'm in over my head. Took the bike for a ride up north - was going up a hill and felt the engine kinda spluttering (like I was running out of gas, which I wasn't), and then noticed that the speedometer and digital trip meter was dead as a door nail - after a while it flickered back into life, but died again.

Got almost home, engine sounded ok but speedo was dead - 5 mins from home and the engine stalled, complete electrical failure and couldn't get it to start. No lights, no horn, no nothing. Pushed it home, where the bike now sits, beaten but not defeated.

Any ideas? Where do I start in order to get my machine back on the road?

Many thanks!

- J
God I hate electrical issues. I'd rather rebuild the motor than deal with them.

Short answer? Good luck... My best advice with general-overall electrical issues is suspect the ECU/brain-box first and foremost. Not, regrettably, a cheap/easy thing to test.
 

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Sounds like my experience when my rectifier went out 6 years ago. Charging system on bike was not functioning properly. Speedo was first indication something was wrong, and then bike quit and I also had to push it home the last 0.2 miles. Recharge your battery, start the bike (if it will start) and measure voltage across battery. See the first three paragraphs here . . . https://sites.google.com/site/vstar1100kb/home/repairs/charging-system.

I believe a bad rectifier can both undercharge and overcharge the battery. I've replaced mine twice now. The first time (6 years ago) the battery was dead after each subsequent brief ride. The second time (a month ago) the battery was swollen and had to be replaced.
 

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After the usual checks, I'd definitely head the direction of the reg/rec. When they fail they can take out every electrical component on the bike.

Do a voltage test on the battery and see where you are at.... then start the bike if you can and check at idle, then at 3,000 RPM. Shut everything off and test again if things tested OK the first time.

If the reg/rec fails, buy only a OEM Yamaha unit or you'll get to do it all over again. Most have upgraded to one from an 05 Road Star...it's heavier duty.
 

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buy only a OEM Yamaha unit or you'll get to do it all over again.
Good advice. The first time it was replaced I had a shop do it as the bike was new (to me). Now, 6 years and 36,000 miles later I'm wondering if they put in OEM or not. With that said, the first OEM one crapped out at just over 11,000 miles so even OEM has some infant mortality issues.

Most have upgraded to one from an 05 Road Star...it's heavier duty.
Very good advice, although I missed this suggestion earlier. Maybe next time. ;-)
 

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After it appears to be fully charged, make sure you test it again while cranking to check the voltage drop.
 

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Discussion Starter #13
Ok, just tried charging the battery overnight - no dice. It still reads 8 volts so I guess the thing is fried and not holding a charge. I've ordered a new one - is there anything I can/should do in the meantime? This totally sucks, did not see this coming at all. Bike was running like a charm until it croaked on the weekend, and I'm burning daylight.
 

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Discussion Starter #14
Couple of things - I just pulled the cover off the alternator housing, uncovered the bunch of wires and found they were all covered in oil, thinking that can't be right -



- might this be a cause of the problem?

Also, here's my multimeter -



- it has a 1.5V and 9V setting on the battery check, but no 12V. Good thing I kept the receipt? Or can I still use it?
 

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Dc 20v on the top left is where u wanna be for voltages on 12v system
 

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Discussion Starter #16
Thanks a million, good to know. This whole electrical thing may as well be in Russian as far as I'm concerned!

I'm gonna get this thing sorted though, come hell or high water...
 

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I wouldnt worry about the oil on the connectors. Oil is an excellent insulator, and it wont stop the contacts from connecting.

Batteries last about 4 years and they can die overnight. Sometimes the lead breaks loose and shorts out cells. There are six 2V cells in there, you lost two of them.

That is a nice meter. You can check the DC volt all the way up to the 500V scale if you want, you will only lose resolution (no decimal places), but yes the 20V DC scale is the best for 12V battery.

BTW, dont use the DC 10A or the other amp settings. To read amps the meter has to be wired in series with the circuit you are checking. (When you measure volts you are touching the probes in parallel with the battery). If you touch the probes to the battery in the amp setting the meter will either blow its internal fuse, or go up in smoke. Its a very common mistake. Half the digital meters in the labs at my work have the amp meter fuse blown out.

When you get your new battery install it (put those alternator wires back together and close it up). then start up the bike.

if you check the battery voltage while the bike is running, it might get as high as 14V while first charging. Im sure there is a thread on this already on the forum. If the battery is not being overcharged, and if it does not drain down below 12V after you ride the bike for a while, you are good.

Odds are very good it was just an old battery.
 

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come hell or high water... hope you are not in the Bahamas tonight!
 

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Discussion Starter #19
Hey KCW, thanks a million for your insight. I'm learning my way as I go with this bike, and the electrical system is to me like the surface of Alpha Centauri - utterly uncharted. I'm almost sure the last owner of the bike (a stand-up guy) told me that it was a new battery, which would mean he would have installed it shortly before I bought the bike in May. I've dropped him an email and will see if he can give me any more info, and I'll have the new battery on Wednesday.

Man, I hope you're right about it being an old battery. The dude in the bike shop today told me I was looking at some serious money if it's the rectifier or stator that's fried.

Thanks again bud =)
 

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Does the battery look a nice and new, or is it kinda scuffed up from bouncing around in the holder.

If it has cell caps you can pop them off and look inside.

If its a new battery the plates will look sharp and clean. An old battery the plates will look mottled and off color.

also if the water in the battery is low (not covering the plates) and it really is a new battery and the water boiled out, that would be an issue with the alt or regulator on the bike.

If the water is low also check if the case is cracked and the water just leaked out - that would be way better than if the bike boiled the water out.

It would take quite of bit of riding on a bike for a bad regulator to overcharge the bike to the point of boiling the water out of the battery. A bad regulator on a car can boil the battery out in less than an hour, but they can put out a lot more power than the charging circuit on a bike.

If you do pop the cell covers off the battery to look inside with a flash light, be careful - that acid is nasty stuff, will burn holes in your clothes, and really mess up your eyes.

I just checked the old battery I had in my 650, its a sealed battery with no caps to check the water level. Yours is probably the same.

Also, if the previous owner said it was a new battery, he might have replaced it two years ago... could just be a figure of speech.
 
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