Sorry, this is long, but then again, electrical problems always are.

I have a 2002 CBR 954 RR, and lately if I leave the bike sit for more than a couple of weeks, the battery will be almost dead. The battery is about 4 years old, so I figured it was just the battery. If I run the bike for about 20 mins, the battery charges right back up, and I never have to worry that the bike won't start again unless I let the bike sit for another 2-3 weeks. I was going to buy a new battery but a new one is so expensive, and since I'm selling the bike anyway, figured I'd just let the new owner know, and take it out of the price of the bike. Plus Autozone tested it, said it held a charge, even under load.

Now, I've been working on an electrical charging problem with my other bike, a '92 VFR 750 F, and one thing I checked for was a leak in the electrical system that can drain the bike while sitting. I'm not having that problem with it, just wanted to check though. Basically, I would think if there is any continuity between + and - battery lead wires while the bike is off, current will leak from the + to the - terminal of the battery, and the battery will slowly drain while the bike is off. I checked the terminals on the VFR, and there is no continuity between them, so no current will flow. Thats a good thing. Now just for reference, the electrical system on the VFR is pretty simple, no computer, no digital clocks, nothing that needs power while the bike is off.

I thought it weird that the battery on the CBR would hold a charge just fine, but dies a few weeks later if not ridden, so I decided to check for a leak in the electrical system of the CBR as well. First I checked the battery voltage, 12.39V. I then disconnected just the negative battery lead. Now someone told me if you hook an indicator light from the negative terminal of the battery to the disconnected negative battery lead and it lights up, you have a leak. I don't have a light, so just checked for a voltage difference. Uh Oh, there was an 11.45V difference between the negative terminal and the disconnected negative terminal lead. Voltage is making it from the positive terminal through the electrical system to the negative terminal somehow. Not good. So I disconnected the battery completely. I checked for a voltage difference between the negative and positive lead wires, there was about a .400V difference that slowly counted down as I watched it (.400, .399, .398, .397, .396, etc) and would keep counting down. I have a really good Multimeter. I then checked resistance between the two leads, it showed about 3.53 megaohms, and counted up while I watched it. Apparently, with the changing voltage and resistance, I'd guess I am dealing with a capacitor or something. While I'm testing resistance(which supplies voltage through my multimeter), the voltage difference and resistance counts up as the capacitor charges. When I'm not testing resistance, the voltage and resistance counts down (capacitor charging and discharging). Now, I'm not sure, but if the bike is off, shouldn't there be no continuity between the positive and negative terminal? Or is the electrical systems on these newer bikes more computerized and complex, and therefore there is a connection between the positive and negative terminal even when the bike is off to like run the clock and stuff. Has anyone ever checked this on their bike? Is my battery old and just needs replaced? Any help would be appreciated.

 

4 year old battery may still be good but will loose charge sooner than one that is new. It's just the facts of life. Start your bike every week or face the possibility of a dead battery... or get a new one.

 

old... get a new one.. but DO NOT go to dealership unless u wanna get raped

 

I'd cycle the battery a couple times.

FWIW, I have a 4 year old battery in one of my bikesand it's stillperforming great.

To save you from asking what "cycling" is:

Hook up a 12V light (from a car, bike, whatever) to your battery and let the light kill the battery completely. Trickle charge to full and repeat at least one more time.
If there isn't any improvement then I'd guess it's time for a new battery.

Don't use a motor to do this as it's not effective enough to drag the battery down. A light is better because it uses a consistant amount of draw and tends to drag batteries down much further.

On a side note: It takes a while for a multimeter to fully stabilize a reading. I wouldn't be concerned if you're seeing .00-something changing. Look for bigger issues like if you were losingtenths of avolt rather than thousandths of a volt.....it saves on headaches.

I think you're lookingintothis wayyy to deeply at the moment. Start simple and progress from there.

 

Fo shizzle! Quit thinking so hard! The first step I would do is fully charge the battery with the charging system or a charger and with the battery OUT of the bike, monitor the voltage. I have seen it (I worked at a Batteries Plus in HS) where the batteries seemed ok under load test but still slowly drained. If it does slowly drain, you can clean it and see if that helps (dirt on the battery can actually allow a path between the + and - leads). Even if you have to replace it (or sell it as is), 4 years is pretty awesome for a bike battery.

The 11.45V that you saw between the disconnected negative lead and the negative terminal is most likely caused by the connection you've caused with the multimeter. With an electrical system, any measurement you take changes how the system is acting, even if it's only in a small way.

When you're battery is 12.39v, it is actually a little low... A fully charged battery should rock ~12.6volts. Once you get below 12, you're pretty much f'd.

Sorry for the scatterbrained responses... If you want more information, ask away, I was kinda limiting my response (rather than going into a tangent about electrical systems)

Good luck!

 

Yeah, I'm going to be monitoring the battery out of the bike for the next week or so. Should their be a voltage between the + and - battery wires when their is no battery connected though? Should it read any type of continuity through the electrical system without the battery connected and the bike off? I think the readings might be from the digital onboards like the trip meters and the clock, etc, but I don't know for sure.

 

guys it's a battery.. it's 4 yeas old.. even if it's not totally bad it will be soon.. KINOME79 - look online they are about 70 bucks.. or go to a battery plus store or somethign along those lines and pick one up, eventually it will totally die on you when you are riding and then it will be a pain

 

Get a batter tender you guys. I was reading my cycle world magazine once and there was an article about a guy who would stick his battery tender on his battery in between rides. He got 11 years out of his battery by doing this. Now I don't stick the battery tender on after rides, but when it is in storage over the winter as it is now, it's on the tender. Get one, they are like 30 bucks at battery plus.

 

my battery was drained to the point of not being able to start the bike after like 2 weeks of sitting. i do have an alarm hooked up to it though so that could be the problem but i always thought that they just drained really easily. maybe i should look into a new battery toolol?

 

Batteries are expensive.. but a new one thats the right replacement will do the trick. I have to agree that your old battery just cant hold a charge while sitting. a voltmeter is cheap and can easily be used to check your battery. if you can charge it out of the bike then let it sit out of the bike and check it again a couple of days later that would answer a few questions. or maybe offer up a twelve pack to the guys at your local shop to check it for you.