Battery on its way out?

[GordonB]

I've noticed a bit of sluggish starting typical of a weak battery. So, Fully charged then checked voltage. approx 12.75 at rest (analog gauge ), drops just below 10 at crank/startup.

10 seems a bit low to me. Thoughts? and Thanks.

[dirtrider]

11 hours ago, GordonB said:

I've noticed a bit of sluggish starting typical of a weak battery. So, Fully charged then checked voltage. approx 12.75 at rest (analog gauge ), drops just below 10 at crank/startup.

10 seems a bit low to me. Thoughts? and Thanks.

 

 

Morning GordonB

 

The 12.75 fully charged doesn't tell us much UNLESS that voltage was taken a good 12 hours AFTER the battery charging. If you measured the static voltage right after charging then you were reading the surface charge & that is pretty meaningless.___ (also, when measuring static motorcycle  battery voltage, a tenth or two on the battery's  fully-charged  voltage can make a BIG difference in battery health  so you really should use a quality digital voltmeter to measure accurately)   

 

As for the just under 10v cranking?-- That is borderline BUT without qualifying it might be close to normal. A very cold engine  with thick heavy engine oil, trans in neutral but clutch lever not  pulled in might give you that number. Under 10v cranking on  a recently ridden motorcycle would be low.

 

About the only real test of your battery is to have a Load-Test done (a lot of motorcycle dealers will do that for free). Even a load test won't always tell you everything but if it fails the load test then  you are probably looking at a new battery.

 

Are you using the PROPER battery charger for your battery (especially if charging it in cold conditions)?  A lot of older trickle chargers or maintainer type chargers are not correct for the newer AGM type battery's & will under charge them (especially in cold ambient conditions).

 

Or, if your battery is 3 or more years old just replace it as a good starting point.

[Pappy35]

I got a couple of slow sluggish (as in barely turning over) starts recently even after having my bike plugged into a Optimate 4 which I thought was unusual. I looked through the records I got when I bought the bike and saw that the battery, a Scorpion, was a little over three years old so I just opted to replace it with a Yuasa. This is the one I got and it was $90 shipped. No more sluggish starts. For items like this that are not very expensive and can leave you stranded I will more often than not just replace them with new and not expend the effort of trying to diagnose them.

[BarnRat]

Just because a trickle battery charger (tender) will show that the battery is fully charged, how it behaves under a load, like starting, is the final decision maker.

 

But try to clean your battery connections -- it may help.

 

[GordonB]

Thanks all.

12.75v taken after 48 hours of charging and sitting in garage no riding. (too much rain here).

Charged with BMW charger.

Battery in 3 years old (BMW Gel)

Cold start 60F.

I typically trade out at 4 years, but may do this one at 3.

I will do a test with a warm start, just to be sure.

[dirtrider]

4 hours ago, GordonB said:

Thanks all.

12.75v taken after 48 hours of charging and sitting in garage no riding. (too much rain here).

Charged with BMW charger.

Battery in 3 years old (BMW Gel)

Cold start 60F.

I typically trade out at 4 years, but may do this one at 3.

I will do a test with a warm start, just to be sure.

 

Afternoon  GordonB

 

I have seen a LOT of the BMW Gel battery's die at or near the  3 year mark (at least drop in performance enough to lower cranking voltage to below 10 volts).

 

If you plan on going anyplace far from home, or far from help then a new AGM type battery would be a highly suggested purchase. Those BMW Gel battery's can have a sudden death, like start fine one time then not the next time (usually on the same ride). 

 

My 3 year old  oem BMW Gel in my 1200RT died on me when stuck in stop & go  traffic on a 95°f+  day in the L/H lane of a 4 lane freeway. I was VERY lucky in that a van about 3 vehicles back had a group of teenagers in it,  they stepped right up &  pushed me off fast enough to get a rolling bump  start.  (unfortunately I never got their names to thank them).

 

 

[Pappy35]

41 minutes ago, dirtrider said:

 

Afternoon  GordonB

 

I have seen a LOT of the BMW Gel battery's die at or near the  3 year mark <snip>

 

This is consistent with my bike's history. One of the previous owners replaced the OEM battery about 2-3 years after the bike was initially sold and then I changed it almost three years later.

[BarnRat]

Yep, 3-4 years on an acid battery (AGM or otherwise).  Here in the desert it's closer to 3 years.  Heat can damage a battery but cold will only lessen the battery's efficiency -- unless in  severe cold where the acid/water mix freezes.

[GordonB]

Thanks all. I always er to the side of caution. New battery time.

[BarnRat]

1 minute ago, GordonB said:

Thanks all. I always er to the side of caution. New battery time.

Is your battery easy to get to?  Some of these older oilheads, especially my R1100S, is a real pain to access the battery -- tucked up under the tupperware and tank.

[Pappy35]

Camhead batteries are right there under the front seat support. One T25 screw releases the hold down, disconnect the leads, put a couple of zip ties through the holes and lift straight up (don't need the zips, that just changes it from simple to dead simple).

[Tri750]

On 3/7/2019 at 7:16 PM, Pappy35 said:

Camhead batteries are right there under the front seat support. One T25 screw releases the hold down, disconnect the leads, put a couple of zip ties through the holes and lift straight up (don't need the zips, that just changes it from simple to dead simple).

Replacing the screw with a Phillips head of the same size helps if one is ever on the road or on the side of the road needing a battery and tools are limited. 

Also, to remove the battery, nabbing the negative post on the battery with Vice Grips and clamping down works well too. 

 

 

[Pappy35]

3 hours ago, Tri750 said:

Replacing the screw with a Phillips head of the same size helps if one is ever on the road or on the side of the road needing a battery and tools are limited. 

Also, to remove the battery, nabbing the negative post on the battery with Vice Grips and clamping down works well too. 

 

 

 

I always have a small tool kit with me but regardless, that's a good idea. It's easy to get the battery out but easier with a couple of zip ties (I keep about 10 in my tool kit).