Tendering a Dead Battery

**nightdevil** · 12-22-2011, 12:46 AM

So yes... I did the unthinkable...
as much as I encourage other to store their bike for the winter... I did not do it on my own...
so at about 8:30pm tonight i just got my friends bike back from the shop and it was a dead battery. So I said... hell let me try to run my bike... and of course... PURE DEAD battery... it did NOTHING! No light, lcd ... nothing... so I had it on the charger since then and now 4 hours later... no lights still...

I figured I would get some minor sign of hope... but do trickle chargers recover depleted batteries? Less than 1year old.

RIQUE · 12-22-2011, 07:47 AM

If you want to recover your dead battery I highly recommend you use a standard charger at LOW amps 6V charge. Charge it until unit indicates full charge. Let stand for 24 hours and charge again LOW amps 6V. I have 12 vintage cars and I alway have to
deal with dead batteries.

**viperclaw** · 12-22-2011, 10:13 AM

He's right. The "tender" type chargers are intended to keep a battery charged and will many times not operate if the charge of the battery is below a certain level.

**HOG SLYR** · 12-22-2011, 11:46 AM

Just to be clear if it's a 12 volt battery use a 12 volt charger and low amperage and with a sick battery I'd remove it from the bike to be safe also do not charge the battery while it's on concrete, put it on a piece of wood.

Fungus Amongus · 12-22-2011, 06:38 PM

Many battery tenders have a built in safety feature to avoid "sparking" from crossing terminals or touching the +/- together. They typically need to sense 3 volts or so before they will begin to charge. Once voltage is sensed, the charger will begin charging. Try tricking the charger by hooking it up to the bike battery, then use another battery to send the voltage signal to the charger. Once it starts charging you should be able to disconnect the jumper battery without disrupting the charger.

**nightdevil** · 12-22-2011, 11:46 PM

well 30 hours on the battery and still no green light... i have sound (fuel) pump (well start of) but no lights... i will give it until the morning ... but if a tender is different than a charger... i may need to go and invest in a charger

**cloudy** · 12-23-2011, 10:01 AM

Many will likely disagree, but I'd take the bike battery out and simply connect it for several seconds to a known good car battery, with the connect time based on what level of arc/spark I got when making the initial connection. Big spark = very short time, and small spark = to 10 to 30 seconds as a rough rule.

This is an old school method to break up the sulfates that may exist on the battery plates and should put enough of a surface charge on the bike battery to get the Tender going also.

Worst that could happen is a ruined/blown up bike battery

, but just a suggestion.

Let the flames begin

.

**nightdevil** · 12-23-2011, 12:15 PM

ohhhhh this sounds interesting
Time to bring out the goggles, lab coat, and rubber gloves

If you don't hear from me in 3 days (I may wait after Christmas)... wish me luck!

**nightdevil** · 12-23-2011, 12:15 PM

ohhhhh this sounds interesting
Time to bring out the goggles, lab coat, and rubber gloves

If you don't hear from me in 3 days (I may wait after Christmas)... wish me luck!

markjenn · 12-23-2011, 02:14 PM

Batteries are relatively cheap and dead simple to replace. Even if you do manage to recover it enough to start the bike, it is likely to have reduced ability to hold a charge and may strand you later. Ante up.

- Mark