Wierd Low Voltage Problem

Kaldari

Registered
I just had a very interesting couple of days, but I'll try and keep things to the point. My bike and battery essentially die after running a short time now.

I took about a 400 mi. ride. Over half of it was fine, but then it started. My FI light came on, and my radar detector was reading low voltage. I pulled over at a McDonald's to make sure the battery terminals or nothing else that's easy to get to came loose. Everything looked fine, so I thought I would just get the seats back on and get back as soon as I could, me still being about 150 mi. away from home. The bike would only turn over about half way. Nothing. I was lucky enough to find someone with cables, and it started right up. I got only 30 mi. when it started happening again. I was hoping it was something I could just ride through, but my gauges stopped reading shortly after, then the lights started dimming, then the engine just died out with some sputtering.

It was the middle of the night at this point, and a jump obviously wasn't going to get me home. So I had a wrecker take the bike and I to a Suzuki shop that was only a couple exits up and happened to have a motel, smelly as it was, walking distance from it.

I got into the shop as soon as they opened the following morning. They weren't outfitted to do any serious work on it, but they did charge and test the battery and made sure the charging system was working. The battery charged for three hours. They put what looked like a glorified volt meter on it to make sure it was reading 14v at 5k RPM. Everything tested fine he said. So I paid them $25 and I was on my way.

I stopped on the side of the road to use my phone a short time later, perhaps only 20 mi. up the road. Well the bike wouldn't start back up. With quite a bit of effort and about 40 minutes, I was able to push start it thinking the alternator would keep it running until I got home, and I just wouldn't turn the bike off until then. I should have known better after it died on me mid run the first time, but I thought it would be fine since the shop said the charging system was peachy. I thought I would just have to order a new battery or something after I got home.

Well, it happened again a short time later, of course. The rest is irrelevant to the problem. Just know I eventually loaded it up in my truck and hauled the bastard back myself.

The kid at the first shop seemed to want to think it was my radar detector, laser jammers, and vizalert causing the problem. I've had these things on there for almost 1,000 miles without trouble however. If they were the problem, what would be causing it now? And why did it only show up well over half way into my 400 mi. ride?

Thanks for the help.
 
Since I know most people just hit the back button when they see a long post like mine, perhaps you guys can at least help me trouble shoot this.

What can cause a bike to have its lights dim then eventually make the bike quit from low voltage while going up the road? I tried keeping it at higher RPM during that second time, so it definitely isn't the battery, right?
 
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Take the battery out of the bike make sure it has water over the plates in each cell if you can open the lids. Next put the battery on a 1-2 amp charger for 8 hours. After 8 hours check the voltage with the charger conected it should be floating between 13.75 and 14 volts if it hasn't reached that voltage get a new battery. If it has disconnect the charger and leave the volt meter on it after an hour the battery should still read between 13.0-13.25 volts if not get a new battery. Batteries sometimes fail due to a crack in the internal bus bars or get a high resistance short between the plates. A battery with either of these problems will pass the first two tests but will fail under a heavy load such as starting or will slowly discharge over a few days. The simplest test for this is to put the charged battery back in the bike connect a volt meter to it and crank the starter briefly the voltage should stay close to 12 volts if it rapidly goes below 11 volts get a new battery.
As far as the charging system goes look in the shop manual( see the sticky for the PDFs of the manuals) for the recomended checks once you know the condition of your battery.
Another thing to check follow the heavy leads from the battery to their next connection and make sure that connection is clean and tight. Any resistance in these connections can cause the problems you are having.

Good luck must go back to my cooling system problems on my 08 Busa.

Doug
 
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If the battery isn't the problem maybe it's the rectifier, maybe it's overheating it while you ride so the problem isnt appearant at the beginning but it's starts to happen later on as you ride. Hook up a voltmeter during a ride to see when this happens.
 
I had this exact problem .... about 1200 miles or so into my new '09, FI light coming on, followed by gauges shutting down and shortly thereafter engine quitting (no fuel).

Turns out it was a faulty voltage regulator. Its failing began as intermittent which made it harder to diagnose, but it didn't take too long for complete failure to sustain any charge.

I bet its your voltage regulator a/k/a rectifier.
 
I had this exact problem .... about 1200 miles or so into my new '09, FI light coming on, followed by gauges shutting down and shortly thereafter engine quitting (no fuel).

Turns out it was a faulty voltage regulator. Its failing began as intermittent which made it harder to diagnose, but it didn't take too long for complete failure to sustain any charge.

I bet its your voltage regulator a/k/a rectifier.

I hear that goes bad a lot esp in the Gen I
 
RusselJ - I was down in your neck of the woods when it happened. Burning along Rt 215. The guys at MR Motorcycle in Asheville were fantastic in getting me back on the road.
 
They swapped my shot one for a new one off a floor-bike, so it was "fixed" by replacing it with a new OEM one.

I will not go on another extended trip before upgrading it. Thanks for the link ... looks good.
 
They go bad on gen 1 because they are located where it gets no air, it gets very hot and prone to failures. Honda was plagued with this problem on the VFR models.
 
They go bad on gen 1 because they are located where it gets no air, it gets very hot and prone to failures. Honda was plagued with this problem on the VFR models.

Is it possible to relocate it about 6 inches so it can get more air?
 
That linked regulator/rectifier apparently dissipates heat more readily than the stock OEM. So should this one be fine for years in its less-than-ideal location, or should I look to relocating it? I really don't want to go through this again anytime soon.
 
That linked regulator/rectifier apparently dissipates heat more readily than the stock OEM. So should this one be fine for years in its less-than-ideal location, or should I look to relocating it? I really don't want to go through this again anytime soon.

With it dissipating heat better it will be better off then an OEM one but for optimal longevity relocating it would be your best bet. I will be relocating mine. Im going to research rectifier relocation to see if any How-To's or kits pop up
 
alot of bikes have them there. there is nothing wrong with the location. some of us gen2 guys are relocating them there.

to the OP get the service manual and check all the pins on the regulator/rectifier per manual.
 
alot of bikes have them there. there is nothing wrong with the location. some of us gen2 guys are relocating them there.

to the OP get the service manual and check all the pins on the regulator/rectifier per manual.

I hate your little bug signature :laugh:. First time i saw it i actually swiped at my screen to get rid of it :banghead:
 
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