Charging problem

[longumd]

Hi everyone,

I just got a 2003 GZ250 a month ago. It has a charging problem I guess. After I got it several days I could not start it, checked the battery voltage, about ~9.5V. So I charged it using a charger to ~12.5V and it was fine for 3-4times rides during two weeks then went back to 9.2V.

I charged it again and checked the current leak, there is no leak there. And I start the bike and checked the charging output (at 5000 rpm) , it was around 13.2V which is less than what the manual said (13.5V-15V).

I haven't done with all the electrical system check, I am wondering if someone had the same problem before and which part I should pay attention to when checking it.

[5th_bike]

I never had that exact problem, just a dead battery problem, so as a suggestion - it could be a contact problem somewhere in the wiring. Usually the bad contact is right at the battery posts.

13.2 V should still be enough to charge a battery. How long were your rides ? I once read (but don't remember the exact numbers) that you need 20 to 30 minutes of riding just to recharge to the level before you started it.

9.2 volt is too low and indicates that you do need a new battery.

(edit) I meant: 9.5 volt is too low, etc.
and, when my battery neared the end of its life it only took a little bit of charge, it didn't really get charged by the bike anymore.
So, try a new battery (don't forget to charge it with low amps after you put the acid in, please read & follow the instructions) and then we'll see.

[blaine]

Originally Posted by 5th_bike

9.2 volt is too low and indicates that you do need a new battery.

:plus1: I agree you need a new battery. :cool:

[alantf]

Originally Posted by 5th_bike

I once read (but don't remember the exact numbers) that you need 20 to 30 minutes of riding just to recharge to the level before you started it.

Living, as I do, on a small island, most of my rides are short. Using my bike as primary transport means lots of short trips down to the supermarket etc. In the (just over) 4 years I've had the bike, the only time I've ever had to charge the battery was after not using it for 2 or 3 weeks while I was on holiday. And that was just a precaution, really. :2tup:

[longumd]

Thanks. I will do a test on my battery also (stop riding it for 2-3days and see if the voltage changed or not). The battery has less than two years from manufactured (Sep/2009).

I had 5-6 times short rides (4miles each) and stop riding for a week, then had 50 miles ride last weekend, I found the voltage was 9.2V this Monday.

[alantf]

Definitely sounds like a duff battery. Try charging it at no more than 2A overnight, then take it to a battery shop for a load test. This'll tell you in minutes if the battery's faulty.

[geezer]

dont forget to check all your connections for charging of corrosoin and use some dieletc grease as well. im sure your only seing 13.2 att he batt cause thats all it wil take due to being bad, but you never know so check those connections too

[mrlmd1]

To say this again for the umpteenth time, a fully charged battery should read 12.8 V. 12.5 V is undercharged by about 20% for an SLA, about 40% undercharged for a VRLA. Your battery is probably toast and the only way to tell is to FULLY charge it and get it load tested. If it won't accept a charge up to 12.8 V measured a half hour after you take it off the charger (to eliminate the "surface charge"), it is NO GOOD. There is probably nothing wrong with your charging system, if the battery won't accept the charge the voltage may not rise to the specs in the manual.
And again, if you buy an AGM battery like practically all bike batteries are these days, it MUST BE FULLY CHARGED BEFORE FIRST USE, or the battery is irreparably damaged and will never hold a full charge, You will start your bike 2 or 3 or 4 times and be back at the shop getting a new battery. Do not rely on the salesman saying to you after filling it with acid or taking it off the shelf that it is good to go. Be warned, if YOU don't charge it up fully to 12.8V it will prematurely fail.

[longumd]

I took it to a advance auto Part store just then, the load test showed it is a good battery.

[mrlmd1]

A few questions - What are you charging the battery with? What are you measuring the voltage with? What was the battery voltage when it was load tested? There is no way it would pass the test if it was only at 12.5V.
And how did you check for "current leak"?

Put the battery on a 2 amp charger overnight. Measure the voltage in the morning when you take it off the charger, wait another 1/2 - 1 hr. and measure the voltage again, then measure it the next day and see if it's stable. If it is, put it back on the bike and measure the voltage when you hit the start button - you are doing your own load test, then see what is is at moderate engine speed (say 3000 rpm).

If your battery truly is good, then the most likely cause of your sudden loss of all electric power is either real dirty or corroded battery connections or a loose one that vibrated loose and lost contact.
But, there is another thing that can lead to a dead battery when you are done riding and park the bike -- to accidentally turn the key instead of to OFF, to PARK (all the way over to the left), leaving on the parking lights which you may not notice being on when you walk away from the bike, unless you specifically look for them. This may be your problem. Look at the key switch. look at the manual (download from this site if you don't have one), and don't do that = problem solved.