Battery problems

[flyingbeagle71]

I left my key on a few nights ago...

It's been on my Battery Tender Jr for two days and still doesn't have enough juice to turn the engine over.  I checked the fluid level in the battery and it's between the lines.  I cleaned the battery terminals.  Nothing.  Finally bump started it last night.  The tach is working intermittently now, even when at higher RPM's, it still cuts out at times.  I rode for 30 minutes hoping to charge the battery a little, but once shut down, it won't restart, won't even turn over....

Time for a new battery???
How can I confirm is the battery is dead???
Does the Battery Tender Jr not have enough oomph to charge the battery???
Is the tach cutting out because the battery is dead???

Any help would be greatly appreciated, it seems like I'm wrenching an hour for ever two spent riding... 

[MarkusN]

Time for a new battery???

Looks like it, yeah. You have subjected your battery to what is known as a 'deep cycle'. Motorcycle and car batteries are not designed for that. (They are optimised to deliver maximum oomph for short bursts.)

You confirm that it's dead pretty much by what you did.

Afraid you'll have to shell out the bucks for a new one. (I'd personally probably try anothe once or twice and then give up anyway.)

[hmmmnz]

lol, the tacho is mechanical. it goes in the front of the engine, make sure that is tight, and where it goes into the bottom check for tightness there, ive never seen or used a battery tender so can't tell you if they charge the batt or not, bump start your bike again, go for a long ride, that should charge the battery up, if it doesn't then either you battery terminals are loose or a couple of cells in the battery are gone, (get your multimeter out and check if you want if under 11v when the bike off chances are a cell is dead)
if it doesnt start after the ride then its time for a new battery

[sledge]

Do you own a GS-E or a GS-F. I believe from previous postings that the tacho system used on the F models is electronic and does not use a cable. If it is the case I suspect the low voltage in the bikes electrical system is causing erratic readings.  Your battery is indeed dead, its been totaly drained and as a result it wont now hold enough charge to turn the starter-motor over. Get a quality replacement, I bought a Varta 6 yrs ago and its never let me down.

[flyingbeagle71]

Thanks for the feedback.  I'll check the battery with my voltmeter tonight.  Maybe I'll try a longer ride before getting the new battery.

This battery is only 2 years old.  I'm kinda surprised it's dead already...

I own an F model, so it looks like my tach is electronic.  I checked the parts diagram and it doesn't show a tach cable for my bike...

[MarkusN]

This battery is only 2 years old.  I'm kinda surprised it's dead already...

Unfortunately age has little to do with it. It didn't like the deep cycle. Such an event can shave a good percentage off the expected lifetime.

[flyingbeagle71]

This is the first time I've drained the battery and I left it on the battery tinder all winter.  The previous owner did other "bad things" to the bike, so maybe they didn't take care of the battery either... 

[Kerry]

Is the electrolyte level acceptable for all 6 cells?  (Just wondering if you "boiled" some of it off without noticing.)

[starwalt]

Kerry has a good idea there. Try using a Hydrometer (aka Battery Tester -- the thing with the colored balls or floating needle in it) to determine if you've got just water or a proper acid solution.  Kmart, Walmart, any auto store has them for less than $10.

MarkusN has another good point. Deep cycling these batteries is often a K-O-D (kiss of death).

While buying the hydrometer, pick up a battery just in case. You can always leave a spare on the tender.

[scottpA_GS]

I left it on the battery tinder all winter. 

I left mine on a wood block in the basement all winter (no tender) popped it in the bike 5 months later and it started right up 

i have a tender and decided not to use it. I know other on here use em w/o trouble. But I think the batt can sit for 4-5 months (as long as its not connected) and still be just fine. Well see if it does it again this winter 

[flyingbeagle71]

Thanks everyone...picked up a battery tester and new battery last night.  The old battery tested fine, but still no zip...  Charged the new one last night and popped it in this morning.  Starts like a champ!!!  Wahoo!!!