Possible battery issue?

[dogger810]

Hey guys I am new to the ST, just bought an 06 on Saturday & rode it home 400mi on Sun (great machine). Anyway, each time I started it I noticed it seemed to turn over slow, I thought it might be the difference from the 800 Interceptors that I am used to. It started each time I refueled on the trip, Mon, & Tues morning for the commute but, today it wouldn't turn over fast enough to start. The original owner said the battery was 2-3 years old, it wasn't ridden much & I don't believe it was kept on a tender either. It seems to be taking a charge on the tender now. Is it possible it just needs charged, even with all the riding? Or is it just time for a battery? Thanks in advance.
Tom

 

[970mike]

Tom,

I would do a voltage check on the battery and if it drops below 10 volts when cranking you need a new battery. Good luck and enjoy that bike.

 

[NorCalBusa]

As posted elsewhere, the only true indication is a carbon pile load test. Most all auto-electric shops, and repair shops worth their salt, have them. Voltage tells you nothing about the battery's health beyond a dead cell or that it is discharged- nothing about its ability to start something (which is what it is used for of course).

 

[T_C]

If you don't already own a battery tender I might suggest you look at some of the alternatives before buying one. Preferably one with desulfate capability.

T

 

[st1300r]

Cheap stuff to check.
Clean and reinstall both ends of the battery cables.
Before resintalling the ground lead check current draw from the battery post to the ground lead. Should be 2.5mA max with the bike off. Then hook the ground lead up. What voltage at the battery do you see idling at 5000 rpm. Should be about 14.2 That will tell you the bike doesn't have a parasitic load draining the battery and the charging system is doing what it's supposed to do.

A battery load test will tell you the remaining starting capacity of a charged battery.
The resting voltage of a battery might tell you state of charge (may be fully charged) but not ability of the battery to deliver power. A fully charged battery that sags too much under starting load or controlled load like the load tester it toast.

Note there's not much reserve in the battery size spec'd for the st1300.
Leaving the lights on while filling the tank etc. won't leave you much for starting the bike.

 

[Bones]

FWIW, the OEM YUASA battery in my '03 lasted 5 years until it wouldn't hold a charge. I replaced it with a Scorpion (linky) and after 5 years the Scorpion is still starting my bike, even on a bunch of recent sub-freezing mornings on the way to Moonshine. I ran heated gear (jacket, grips and/or gloves) pretty much every day on that 10-day trip, plus 55w headlamps and 35w fork lights and a GPS. I won't be buying any more OEM batteries that cost more than twice as much and don't last longer than a Scorpion. From next month on, the Scorpion will have lasted longer. YMMV

+1 on a Battery Tender.