Help! Cranks slow and won't start. FIXED

I went to start up the Silverwing this afternoon, and it cranked rather slowly. The headlight is fairly bright and all other lights are lit as well.

I put it on the trickle charger for a few hours and took it off after the charger indicated it was charged. It still cranks slowly and won't start.

I measured the voltage across the battery terminals.

12.76 - just after the charge, and after trying once to start
12.26 - key on, headlights on
11.20 - while cranking

Last time I used it, it ran flawlessly. Last use was last week; the Vespa got to go on the camping trip last weekend!

Does this sound like the battery is a goner? It seems that it loses too much voltage when under a load. The previous owner said he had just installed a new battery before putting it up for sale (this was two years ago this weekend). It is not a Honda brand battery as far as I can tell.

Next question - where is a good place to get a new battery? Online, Walmart, auto parts store???

Thanks for any and all help.

Philip


Edit @ 9:00 PM

I tried a few more things. I used a car charger at 10 amp setting for about five minutes (maybe less). I also pulled each of the fuses underneath the seat (none were burned, mostly shiny but with a little corrosion around the edges).

I then gave it another try at cranking. A bit slow sounding but better than before. When it wouldn't start, I gave it a little throttle a few times while it was cranking and it fired up! Idle was a touch rough for 10 seconds or so, then settled into place. After revving the motor a little (3000 rpm or so), and a bit of idling, I used the key to turn the motor off. Tried starting again and it started as normal. A 10 minute ride and it runs fine.

Thinking back, I remember it doing something similar once before. A neighbor told me to give it some throttle and it fired up then, too. Perhaps a sensor in the fuel injection system was mixed up. Whatever it was, I'm glad to get it running. If it happens to you, remember to give it some throttle when cranking the starter (just be on the center stand, or hold the brake).

buddy19520 wrote:

The previous owner said he had just installed a new battery before putting it up for sale (this was two years ago this weekend).

Two years is not that old.

I had the same problem with mine about a month ago.

Gave it a little throttle and it fired right up. It has started and run well ever since.

My experience----try Batteries Plus----they can load test old battery and probably sell you new one that fits.

If bike is used everyday, more than 10 mile trips, etc. Battery seems to last long time. Standing, used only now and then, the battery tends to have shorter life.

Anything over 2 years is good luck, but OEM battery on my Kawasaki Concours did last 5 years....and I changed it due to fear or dislike of walking...Not easy bike to bump start. That bike was spare and only got 56,000 miles of use in 5 years, but run at least once a week.

I never add electrical accessories, which can cause extra load on system that was not designed for it.

john grinsel wrote:

If bike is used everyday, more than 10 mile trips, etc. Battery seems to last long time. Standing, used only now and then, the battery tends to have shorter life.

Anything over 2 years is good luck

I'll second that John! A general rule of thumb from my few miles of riding is that two full seasons on a new “Un-Tendered Battery” is reasonable, any more will tempt fate.

When you start your quest for a battery, I would be looking for a gel battery.

Thanks to this forum, some one turned me on to them and have pleased so far.

Turns out they last longer, do better under load, and take a charge faster. they are sealed so no maintenance needed. Per say

Also I would be willing to bet that the previous owner knowing he was about to sell did not invest in a good battery.

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