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Motorbike does not start with battery under 14V

7K views 33 replies 16 participants last post by  trapperdog 
#1 ·
Hi,

I have a V-Strom K8, always owned by me that it is since temperatures fall down that has some problem to start, but not always. The sound is the typical one of an exhausted battery however if I detach the battery and test it, I did it twice in two occasions the bike would not start, it seems to be pretty good: 12,4V the first time and 13,3V the second time I tested it. Then I charged it and the voltage arrive at 14,2V. Battery attached and the bike started like a charm, all the two times.
The battery is a Motobatt Mbtx12U and is only one year and half old. I use copper paste on the plugs so the conduction is perfect. Oil and oil filter are new and clean.
Before this battery I had the original Suziky for 8 years and I never had problems even if I let the bike stopped for the whole winter with battery plugged in. Then it started immediately after winter.

How could be the problem? Could it be that even if I have 12V the battery cannot bring enough power the the engine to start?

Thanks for any help.
 
#2 ·
An update: this second time the moto starts with the battery at 14,02V, it however had some problems to start, it takes few seconds to do it.
Could there be engine spark plugs?`They have 7 years and about 8000 km..
 
#4 ·
First, a battery at 12.4 volts after sitting is on the low side. 13.3 volts shouldn't happen unless it was just on the charger! It takes some time for the flash charge to come off a battery when disconnected from a charger. Couple hours at least for accurate measurement.

Two things come to mind. First is that the battery is bad. How old it is means nothing. If it is not holding a charge, that tells you it needs load tested at least.

On the other hand, if the battery isn't being charged properly, it cannot keep enough power in it to start the bike. If a 650 I would wonder about the stator, if a 1000 I would suspect the magnets in the rotor have moved together. Which can be hard on the stator also.

What is needed is a voltmeter on the bike while running. You want to see 13.8-14.4 volts when above say 3000 rpm. If you are seeing in the 12 volts range or less, the charging system isn't working properly and no battery will work until that is fixed.
 
#5 ·
From your report of the starting sound, together with more difficulty at lower temperature, I think there is excessive resistance in the circuit. More torque and hence current is needed at lower temperature, which drops the voltage in proportion to current times resistance. In your case, the voltage reaching the starter motor is dropping too far. The suggestions to check for loose connection (which would increase its resistance) and to do a load test (which is sensitive to battery resistance) are both good and are clearly indicated here.
 
#6 ·
Load testing keeps getting suggested when a battery thread comes up.
No need to pull the battery out of the bike. Leave the meter on the battery and hit the starter. If it drops significantly and the bike doesn't start, probably you have a bad battery.
Or with the key off the reading is 12+ volts, what does it read when you turn the key to on and the headlights come on?
Load is a load. Just mind the readings on the meter.
The load test the auto parts store or shop use is a big resistor.

Then there are you tube vids on how to clean a battery and get some more life out of it. But you'd be on borrowed time then.
 
#7 ·
Load testing keeps getting suggested when a battery thread comes up.
No need to pull the battery out of the bike. Leave the meter on the battery and hit the starter. If it drops significantly and the bike doesn't start, probably you have a bad battery.
Or with the key off the reading is 12+ volts, what does it read when you turn the key to on and the headlights come on?
Load is a load. Just mind the readings on the meter.
The load test the auto parts store or shop use is a big resistor.
I agree with this in principle. However: It can be difficult to see what voltage drop during starting is normal because cranking does not usually last long enough for a modern DMM reading to stabilize. It is common for 12V batteries to drop to 6 Volts during cranking, so don't take that or a higher cranking voltage to indicate a bad battery.


Checking voltage drop with just the headlight and ignition load is good to do, when the bike is starting normally and you have a DMM (or other voltmeter.) Then you are poised to objectively determine whether battery or connection resistance has increased badly. There are some confounding factors to beware of: When the battery is fully charged, and especially if it has been left on a charger, the voltage can drop hundreds of mV just because, during overcharge, a different reaction is occurring than the one which provides the greatest portion of the discharge energy. The drop to attend carefully is the one which starts in the 12.6 to 13.2 V (or thereabouts) plateau part of the battery's discharge curve. This can be tricky to interpret because the drop is many times smaller than what occurs when cranking current is drawn from the battery. When load testing with your headlights and ignition as load gives ambiguous results, a load test with a known, high current load will distinguish starting failure due to an overly resistive battery from one due to a starter motor gone bad due to a shorted winding. That said, I would view the load test at a shop as a late step in the troubleshooting process.

Then there are you tube vids on how to clean a battery and get some more life out of it. But you'd be on borrowed time then.
If the battery's internal resistance has gone up too far, there is no more life to be had from it that you really want to rely upon. Either something has broken inside and will be unreliable even if it happens to reconnect, or the plates have gotten so deteriorated that they are at the end of their useful life. Neither condition can be feasibly repaired outside of a battery factory.
 
#8 ·
"If the battery's internal resistance has gone up too far,"

I think the sulfites have built up on the bottom of the plates and the alleged cleaning and wrincing washes it away. Still seems like an effort in futility.
But like mounting a tire igniting hair spray it's kinda interesting.
 
#9 · (Edited)
I think the sulfites have built up on the bottom of the plates and the alleged cleaning and wrincing washes it away. Still seems like an effort in futility.
Not sure how legit it is, but I had a similar experience with an AGM battery in my 4-wheeler. The dealer claimed it had a new battery installed when I took delivery. Even early on it struggled to start at times, but would crank forever just fine. Also threw the power steering fault code all the time (even with the engine running). After it sat unused for a couple of seasons, I researched a ton while looking for a good battery charger / maintainer and settled on the PulseTech XC100-P.

Since the battery had been sitting for several seasons it was only reading about 8.5 volts when I removed it from the wheeler and attached the PulseTech Charger/Maintainer. 8.5 volts is WAY below the minimum 10V of a discharged battery and I was concerned the PulseTech would consider it a bad battery and give up. However, it kept pounding away and gaining ground and after a couple of days it read "100%". I wasn't sure if it was completely done de-sulfating, so I called PulseTech. They recommended leaving it attached to the Charger/Maintainer for about a week. I think I actually left it for 3 or 4 weeks. Afterward, the resting voltage was right around 13V. I tested the resting voltage again after 2 months sitting on the bench and it was still above 12.8V. I put it back in the 4 wheeler and it starts right up, and has not had the power steering fault ever since.

I actually use two of these Charger/Maintainers now so I can rotate them between the 4-wheeler, the Vee2, and the cage (since it sits for weeks at a time when I'm commuting on the Vee2).

Interesting story about the battery in the cage. I have a dashcam that records while parked. This of course taxes the battery because it discharges a bit more than it should. Even though I will drive it for an hour at a time to charge it up, it will progressively get a weaker and weaker start cycle. Until eventually when I get in the car it says "System shutdown to conserve battery". It always starts, but once I get close to or receive that message, I hook it up to the PulseTech for a couple of days and it is good to go again. I wish someone offered a reasonable AGM battery that would drop in for that thing, I'd buy one in a heartbeat. As it is I'd have to modify the battery box, or buy the one and only current direct replacement option that is about $450 (cheaper to just abuse the stock battery - I can get 4 of them for that much coin). Which I don't understand for two reasons... 1) Ford uses that same battery in a zillion cars / trucks / etc. - the aftermarket should be all over that! 2) Why is a modern new car (and zillions of others) furnished with a battery technology from 50 years ago? It is not even maintenance free! Yes, I have to pop the top to check and add distilled water... Come on, where's my AGM? While not necessarily an actual deep cycle / starting hybrid battery, at least the AGM would handle the minor discharges from the dashcam better than the stock battery.

The PulseTech is a bit pricey, typically about $70. But it has paid for itself already by restoring my neglected / abused batteries that would have otherwise required replacement. However, all of this will only help an otherwise healthy battery. It only claims to remove the sulfates, it can't restore used up lead plates or fix bad internal connections.
 
#12 ·
Sounds like it could be one of 2 things.

The battery does not have enough CCA's within itself to do the job you are asking it to do, try a jump start to see if you notice a difference ?


The starter motor is getting worn and dirty, this will often show up as spinning fast one start and slower the next.

I only ever once had what I thought was going to be a staring problem with my 09 Wee, the battery was a little low and I could hear the motor was spinning slower than it should have been, I cracked open the throttle and it fired right up, give that a try next time.
 
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#14 ·
Thanks a lot for all comments and tips.

Right now I tested the battery on the bike and measurements are those: 13,8V when the bike is off, 12,6V when I turn the key in start position, around 4-6V when I push the clutch lever and push the start botton. Is it a normal behaviour?

I will move on to check the starter engine and both spark plugs, the quickest two checks I can do because already have info on how to do those.
 
#15 ·
13.8 volts is too high for a battery in the bike with the ignition switch off. Unless you still have a charger attached to it or just removed the charger from the battery.

12.6 volts is too high for a battery with ignition key on, engine not running. Again, is the charger still attached or just removed?

But the 4-6 volts with the starter button depressed tells us everything. If the battery was at or near fully charged, 4-6 volts tells us the battery has failed.
 
#17 ·
Take a voltage reading, remember it.

Turn on the ignition.

Let it sit for 2 or 3 minutes.

Take a reading, remember it.

Press the start button without pulling in the clutch, this will turn out your lights, now take a voltage reading at the battery at the same time, remember it.


Now pull in the clutch leaver and try to start the bike while taking a voltage reading. remember it, "try not to have the bike start"


You are going to be pulling voltage out of your battery during the tests, the important part is if the battery can recover some of that lost voltage while it is just sitting there doing nothing.


Anything above 12.8 means very little so we will start at around 12.8v, when you crank the motor it may drop to around 11.2v, you stop cranking and you maybe around 12.5v.


You now sit and watch the volts, if they start to climb back to around 12.8v your battery is Ok, if it stays around 12.5v your battery is on it's last legs, if the voltage continues to fall your battery is stuffed.


Of course you need to put your numbers in there not the examples I have give you.
 
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#18 ·
Take a voltage reading, remember it.

Turn on the ignition.
Bike off: 13,6V (please note that my battery is a 14.0V one)
Turned on ignition: 12,4V

Let it sit for 2 or 3 minutes.

Take a reading, remember it.
9,1V

Press the start button without pulling in the clutch, this will turn out your lights, now take a voltage reading at the battery at the same time, remember it.
10,05V

Now pull in the clutch leaver and try to start the bike while taking a voltage reading. remember it, "try not to have the bike start"
3,03V
 
#21 ·
Battery sounds shot to me too.

Do you have a car with a 12V battery? You can run jumper cables from the car battery to the bike battery. DO NOT START THE CAR. Try to start the bike that way. If it cranks fine, that confirms what everyone else is telling you about the bike battery being trashed.

Age is only one factor in the length of a lead-acid battery's life. How it was maintained can shorten its life significantly. If it was left at a low state of charge for even just a few weeks you will permanently sulfate the plates. This 'hard sulfation' can't even be recovered by battery chargers that claim to desolate. The rapid voltage drop under load from 13.6V (which I don't believe is the actual resting voltage of the battery) to 3.0V points to an unrecoverable battery.
 
#22 ·
Thanks all.

I understood it is the battery even it has only one and half year! I already sent a reclamation to the reseller.

Spark plugs were also to change and I did today.

After that I recharged the battery with a charger and immediately the motorbike turned on....but it does not last that longer. Can´t rely on this battery :(
 
#23 ·
Sounds like you have a bad battery. I went through two batteries on my ATV over a span of 3 years. They acted the exact same way as you describe. Batteries lasted just beyond the 1yr warranty. Manufactured in China. Spent an extra $30 and bought a Yuasa battery. That was 8 years ago. Battery is just now getting a bit weak. Soon be time for another Yuasa!
 
#25 ·
I with him 3.03v is very very bad.

What I'm looking for is when you get the reading of 10.05v turn everything off & leave the meter in place, watch it for a good few minutes, a good battery will start to climb back to and get close to 12.8v, a poor battery will recover a little and a bad battery will recover none or continue to lose power.

Being 14ah means it can take a greater load and will need a greater/longer load for this test but it is still a 12.8v battery and any voltage above that means very little and will burn off very quickly.

The key is a batteries ability to recover when sitting without a charge being applied.
 
#26 ·
Hi mates, I thank you all for the support and help.

Here I am with the new battery which is an identical one since the seller granted to send me a replace. The bike started immediately also after the second timen and I never had the tension drop I had before.

In posts below I made a video of the first start with the new battery.

Is it everything ok on the electrical side or maybe the battery is over-stressed?

Thanks in advance
 
#29 ·
In posts below I made a video of the first start with the new battery.
Am I seeing that right, you are getting ~16 VDC at idle? That is way too high, at idle its typically 12-13VDC and at higher RPMs around 14VDC.

Is it everything ok on the electrical side or maybe the battery is over-stressed?
I did not follow the thread but, yes, looks like the charging system is overcharging the battery which will kill a battery in no time.
 
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#34 ·
Shouldn’t make a difference, but your +pos and -neg multimeter cables are plugged in the wrong position (switched) on the multimeter. I’d also retest with a higher quality and known reliable multimeter to be sure the numbers are accurate
 
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