Battery or R/R?

[Anonymous]

Hello I keep boiling off the water out of my battery. Although slowly, it's a bit annoying. So I checked the Volts coming to the battery and at idle it's hovering around 13 volts and at 5000 rpm it's 14.3 volts but does not go higher. While 14.3 volts is fine at the top end should the R/R be putting around 13 volts at idle(1200 rpm)? seems high to me. The battery is a "Ho chi mihn" special I got at Canadian Tire and have had it since the begining of last summer, so is it because its a cheap battery? SOme cells seem to hold watter better than others. Maybe I'll buy another cheap battery and see if it will last another year and a half. It only starting doing this in the last 2 months or so. Lots of power to system. I'm thinking it's just the battery. How long do they last?

[earlfor]

Re: Battery or R/R?

The voltages you measured are in normal range and not excessive. My best guess is the problem is due to lack of quality control in manufacture of the battery. Apparently, the amount of material in each cell is not the same. I think a better grade battery would eliminate your problem.
The best deal is to buy a premium, maintenance free battery and not have to think about boiling it dry. It would also outlast about 4 or 5 of the cheap ones too. :-) More money initially, but in the long run, a lot cheaper.

Earl

Hello I keep boiling off the water out of my battery. Although slowly, it's a bit annoying. So I checked the Volts coming to the battery and at idle it's hovering around 13 volts and at 5000 rpm it's 14.3 volts but does not go higher. While 14.3 volts is fine at the top end should the R/R be putting around 13 volts at idle(1200 rpm)? seems high to me. The battery is a "Ho chi mihn" special I got at Canadian Tire and have had it since the begining of last summer, so is it because its a cheap battery? SOme cells seem to hold watter better than others. Maybe I'll buy another cheap battery and see if it will last another year and a half. It only starting doing this in the last 2 months or so. Lots of power to system. I'm thinking it's just the battery. How long do they last?

[Redman]

I say a couple seasons on a battery (ordinary battery from auto parts store). I used to try to get 3 or 4 seasons out of a battery, but was causing myself more trouble than it was worth.

The voltages you mentioned are not high. I understand that if R/R is not working (weither failed or ungrounded) the voltage can go into 15s or 16 volts and then thats when you "boil" off the battery.

You have checked the charging voltage, which is okay, and you have gotten 2 seasons out of the inexpensive (I assume) battery. So i would agree with you idea of trying a new battery.

[Anonymous]

I think you are right guys. After I took a look today it did seem a little grim in the cells. The cells that seem to "boil" out the most are on the 4 on the right hand side. The 2 left don't really. I could see that if 2 cells are semi-dead (hence no boiling) 4 cells are trying to do the work of 6. So having 100% of the juice go through 60 percent of the capacity I could see cause some problems. I topped up the low water cells, drove for 15 minutes and voilia! The bike can turn over no problem now, so obviously the bike is charging. I'll get another battery tomorrow just in case. Any idea how much a sealed battery would be in the Toronto, Canada area? The Canadian Tire special was about 50 bucks or so, is it safe to assume a "Maintenance Free" battery would be double? If hypothetically a sealed battery overcharged would it explode? Or does it have some sort of logic cicuit, mechanical or otherwise, that shuts off the juice when it's full? If I do have a faulty R/R I don't want to blow my balls off!! It doesn't look like my charging system is faulty, but best to play it safe. Thanks for your help.

[earlfor]

I havent any idea of Canadian prices for maintenance free batteries. I am guessing somewhere close to double the cost, but its a wild guess. :-)

You dont need a logic circuit to shut off charging current. As long as your charging system is functioning as it should (in the correct range), it will balance to the battery. You can consider voltage as electrical pressure.
Once the battery reaches a full charge level, the voltage in the battery balances the incoming charging voltage. The system is self balancing.
Excess charging current that is "pushed" back by the battery is lost as heat by the cooling fins on the R/R. I've never seen a motorcycle charging system with enough capacity to blow up a battery anyway. maybe some of the new bikes could do that, but I dont think it is a possibility for a GS. :-)

Earl

Any idea how much a sealed battery would be in the Toronto, Canada area? The Canadian Tire special was about 50 bucks or so, is it safe to assume a "Maintenance Free" battery would be double? If hypothetically a sealed battery overcharged would it explode? Or does it have some sort of logic cicuit, mechanical or otherwise, that shuts off the juice when it's full? If I do have a faulty R/R I don't want to blow my balls off!! It doesn't look like my charging system is faulty, but best to play it safe. Thanks for your help.

[Anonymous]

Yep turned out to be the battery. Next one I get will not be cheap.

[Mysuzyq]

Yep turned out to be the battery. Next one I get will not be cheap.

Do let us know if you have success finding a compatible maintenance-free battery at a reasonable price.....I may need a new battery next season, & may go with one. I got 2 1/2 seasons with the Yuasa so far, but yesterday it was cranking a bit sluggishly .....hopefully may just need charging, due to infrequent use of late. BTW Rider1, what kind of GS do you ride?

Tony.

[Anonymous]

Yuasa makes a compatible maintenance free battery. I have and '84 GS750EF with the full fairing. It's the same battery size as my '81 GS650G and the same as my friends 81 Katana 1100. I'm figuring they are probably pretty standard type sizes.