Battery gone dead again

[Shot]

I ride my bike every week (2004 RSV); in the last couple of months my battery has lost juice and won't crank. As we speak I have it on low charge. Advance has checked the battery and says it just needs charging and nothing is wrong with the battery itself. The battery is two plus years old.

 

Any ideas out there. When I crank up today I will have jumper cables with me but that ain't the solution.

[Guest]

You need to check out whether the bike's charging system is charging the battery. A digital multi meter (DMM) will tell you this.

 

My browser isnt letting me cut and paste but do a search here on charging systems and you should find what you need. There was a pretty thorough one involving my bike about 6 or 7 pages into the charging system search page.

Edited September 20, 2010 by Ruffy

[etcswjoe]

If your charging system checks out take a good look at all your cables. You may have a nick or chaff in a cable or corrosion on a connection. Also check any items you have that can receive power with the switch off they may be drawing current continuously.

[frankd]

You should measure about 14.5 plus or minus .5 Volts with the battery fully charged and the engine revved up to about 3,000 RPM.

 

If you don't have a digital voltmeter, an analog one will do, but read it carefully.

 

If you don't have access to either, charge your battery fully. Remove the charger and start the bike. Shine the headlight someplace where you can see the reflection (a wall or something like it). While the bike is still cold, turn the choke all the way off so that it will idle slowly and then look at the headlight reflection as you blip the throttle. Right above idle you should see the lights get noticeably brighter. If so your charging system PROBABLY is working.

 

How dead does your battery get after a week?? Is a little low or is it 100% discharged?

 

Frank

[V7Goose]

I ride my bike every week (2004 RSV); in the last couple of months my battery has lost juice and won't crank. As we speak I have it on low charge. Advance has checked the battery and says it just needs charging and nothing is wrong with the battery itself. The battery is two plus years old.

 

Any ideas out there. When I crank up today I will have jumper cables with me but that ain't the solution.

You say you ride your bike every week, but you do not give enough information. How often, and how long/far between starts? Do you ride it once a week for 7 miles, or every day for 30 miles? In general, you need to ride for at least 30 minutes after a start to fully re-charge the battery, and that assumes your battery STARTED at full charge. Of course, that amount of time you actually need to replace the starting charge depends on the average engine RPM, how much current is being sucked up by accessories (including the radio), and the exact state of the charge when you start.

 

It is very very common for people to slowly destroy a battery by rarely ever allowing it to regain full charge. The only way to know for sure what charge state the battery is in is to use a digital volt meter. The battery in this bike must be at a minimum of 12.8 V (after sitting for several hours) to be considered at full charge (the voltage right after shutting down the engine is of no value - you must wait for the float charge to dissipate).

 

I do not know of any way for a shop to actually check a battery and say it is good but only needs charging - you CANNOT check it until it IS at full charge.

Goose

Edited September 20, 2010 by V7Goose