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Second Dead Battery

13K views 89 replies 45 participants last post by  DJ123 
#1 ·
The bike is less than two years old. Got a jump from roadside assistance and was able to get home, but it wouldn't re start. Luckily I blew off the 340 ride through the state forests I had planned for the day, and was only about 8 miles from home.
 
#47 ·
It is the exact same unit which Deltran sells for much less, but without the CANbus stuff.
 
#50 ·
[QUOTEThe bikes alternator is not really up to the job, thus the battery often takes the brunt of the demand. I believe this may well be a factor in the early demise of peoples batteries[/QUOTE]

Is the bike capable of running all night with lights on and an extra 70 watts being drawn off for a heated jacket and gloves ? My Honda CBF125 can (alternator output 170 watts) - surely the BMW would not blink at such a task. Or, would it?
 
#52 ·
A word of caution about running your bike with a run down battery . . . don't do it too often or for very long, especially in hot weather. I believe it says in the owners manual and even in car owner's manuals to never use the vehicles alternator to charge a dead battery, as in after a jump start. Alternators are not designed for that sustained heavy task in addition to the normal electrical load and can be permanently damaged by overheating.

In the case of our F800 bikes and most every motorcycle you are risking a very expensive stator/rotor assembly and/or regulator rectifier, like we read about in RockBottom's post. That means when your battery barely starts the bike or worse yet, you had to jump start it, you are risking some very expensive repairs . . . . in addition to the battery!

It won't always happen that way, because dying batteries frequently don't hold a charge, so they do not draw very much charging current after the jump start. But sometimes they do, and you won't know it unless you have an Ammeter connected in the charging circuit. If you have just a voltmeter there is an indication the battery is eating everything the alternator is putting out and it is that it takes more RPM to pass the break even point (battery at rest voltage). In addition, it'll take much more RPM than usual if the high beam or driving lights are also on.

.
 
#55 ·
I think you (or that vendor you link to) may be confusing the BT and BT+. They sell 6, 8 and 12-volt BT Plus models and one pink one (!), but the 12v BT+ models all are designed for AGM cells. Deltran on its own manufacturer's site does not list any gel-specific chargers.

See http://batterytender.com/

Here's from Deltran's own web FAQ:

13. How is the Battery Tender Plus battery charger different from the Battery Tender battery charger?
OVERVIEW and COMPARISON: The Battery Tender and Battery Tender Plus battery chargers are both designed to provide a quick, economical means to recharge motorcycle and engine start batteries used in other power sports equipment. Typically, power sports engine start batteries are in the 12 Ah to 20 Ah capacity ranges. Both chargers are constant voltage type with precisely regulated output current limits. Both chargers have a regulated, nearly constant 1.25-ampere output charge current during the bulk charge phase. Physically, there is virtually no difference between these 2 chargers. Both the Battery Tender and the Battery Tender Plus operate in 3 charge modes, bulk charge, absorption charge, and float charge.

RECHARGING AGM BATTERIES: The primary difference between these 2 chargers is that the Battery Tender Plus was specifically designed to accommodate the charging requirements of the new, Absorbed Glass Matte (AGM) style batteries. To achieve that goal, it was necessary to modify the absorption charge mode in the following way. The Battery Tender switches to float mode when the charge current drops to 0.5 amps. The Battery Tender Plus switches to float mode when the charge current drops to 0.1 amps. The result is that for an extended period of time, not to exceed 8 hours, the Battery Tender Plus output voltage will be held at a constant voltage that is significantly higher than the float voltage.

With the Battery Tender, the switchover at 0.5 amp results in an absorption charge mode length of approximately 1 hour. During this 1-hour period, the battery charge voltage is held constant at a value of approximately 14.3 volts. Because of the slightly higher voltage recharge requirements of AGM batteries, and because AGM batteries require a longer period of constant voltage absorption, the Battery Tender Plus controls the output voltage at 14.4 volts while it waits for either the charge current to decrease to 0.1 amp or for the absorption charge mode control timer to expire. The end result is that the Battery Tender Plus absorption period is longer and at a slightly higher voltage than that for the Battery Tender.

-dan
 
#56 ·
on my bmw charger manual and on the package, it says that it charges FLA GEL and AGM batteries? though it comes with a accessory socket, it cannot charge through the socket due to Can-BUS. BUT, it does come with pigtails for charging through a SAE socket.

http://www.ascycles.com/detail.aspx?ID=1357

in its product description it says FLA GEL and AGM?

my 2010 bike came stock with an AGM battery.
 
#57 ·
WOO HOO! i picked up a battery bug today and installed it!

Amazon.com: Argus BB-SBM12-PS Battery Bug Battery Monitor for Motorcycles and Power Sports:…@@AMEPARAM@@http://ecx.images-amazon.com/images/I/41mDWKYxCtL.@@AMEPARAM@@41mDWKYxCtL

IT...IS...A...UGLY...BRICK...

I couldnt push myself to install it on the dash so instead i wired it and dragged it to the rear, under my seat, near the tail. It's great there in my opinion -

1) the thing will beep for 30 seconds (according to manual) of a failing or near death battery.
2) it does a good job reporting how much battery juice is left in % and what the battery juice was when last cranked.
3) i can see myself every oddball blue moon to unlock the rear seat and glance to check out battery % while i do other things when the seat is off (like adjust my airhawk)
4) the thing is on all the time so i can check the juice when engine is off as well.

I cant find info on the battery draw it takes to power the little bug but i'm assuming it cant be that much.

happy camper here, well worth the piece of mind. still think its a fugly brick :(
 
#58 ·
I've been considering the Battery Bug as well Crick. Not sure of the placement either. I would prefer to check it more consistently. Sudden Battery Death Syndrome would definitely dampen my day. Will it fit on the small ledge underneath the computer? Given the measurements on the web site I think the overhang may be minimal.
 
#59 ·
CORRECT - mine is velcroed under the computer and small overhang but nothing to worry about. On a new battery it dropped to about 60% but has remained there ever since. A good product. Enables me to keep an eye on voltage (usually about 14.2ish volts) when riding. And it is connected direct to battery and always on. Have left the bike for weeks before and seen only tiny change in battery so cant take much power to run it.
 
#60 ·
The Bug sounds useful, but I have to wonder whether it can predict SBDS (Sudden Battery Death Syndrome)?

If as speculated here, the failure is due to vibration severing or shorting the connection between cells, then the bug will only tell what you will already know -- that the battery has gone from perfectly good to useless in a matter of seconds while you were riding.

-dan
 
#61 ·
#62 ·
Looking for some opinions. 09ST with just over 8k miles I have owned the bike 1 year and I know it was on the dealer show room floor for at least 8 months before I bought it last year. I always hook the bike up to the battery trickle charger at the end of the day. When fully charged the green light will stay on. When charging or about 80% charged there will be a flashing green and red light. The last few times I have noticed that the bike never gets to the full charged green light on all the time phase. It only gets to the green and red flashing phase. Might this be a sign of the battery getting ready to crap out? I should probably have a voltage meter hooked up but I thought I would look for some opinions also. Thanks. Ken
 
#63 ·
as the battery gets older, doesnt the energy discharge to crank the motorcycle get higher and higher? in which case, it would take longer to charge.

even tho the motorcycle is on the show floor, they usually dont install the battery until after you purchase it... unless its used.
 
#64 ·
Uhm interesting though.
If the voltage drops then the current will need to rise but assuming the load is fixed impedance (actually it's a motor so inductive so much more complicated to work out)
then the current would drop proportionally to the voltage. Resulting in less crank energy.

However assuming the batteries charged the voltage would be high. On the old lead acid batteries sulphation of the plates could reduce the current available and the capacity of the battery but I think Gel batteries suffer less (if at all) of sulphation.
 
#65 · (Edited)
Not being brilliant on electrics can anyone confirm that it is OK to use my Optimate charger on my battery through a tail direct to the battery as I am doing? The bike is '08, it is the original battery and the bike has only done 2.5K miles. I presume (hope) it was kept reasonably well charged up before I bought it by the boys at Bracknel, from whence it apparently came! I have had no troubles with it, assume it is a gel battery and thought I had it all sorted out but am beginning to wonder now! Any advice would be gratefully received!
 
#69 ·
I have an Optimate ll charger purchased about 10 years ago. When I bought my ST in '07, I was a bit concerned about instructions in manual re charger / methods. Therefore spoke to dealer and also to tech rep at Optimate. Both confirmed that old Optimate ll was fine to use to charge battery in situ via pigtails wired direct to battery [you can only charge via built in power socket if using a canbus compatible charger]. I made and fitted a cable with in line fuse connected to battery posts. Connector for charger connection can be fitted with weather proof cap and stowed behind fairing.
If bike to be unused for more than 3 or 4 days, I hook up the Optimate and leave "on charge" until next ride.The original BMW / Exide battery suffered the common, sudden death failure at just over 2 years but I do not attribute that to Optimate.
 
#66 ·
DJ, I have the same setup, with the tail direct on the battery. Had the battery totally die on me, but must have been due to me messing with the electrics and the lights when installing and testing my HID's. Battery charges fine and cranks perfectly and i have no issue (yet)
 
#67 ·
Canadian Battery Gremlin!

Hi folks. I also had some battery troubles but was quickly sorted out by the dealer [ atlanticmotoplex.com ]in Moncton N.B. [ Canada ] I have a 2008 F800S that I bought in 2009 [ Sunset Yellow the fastest colour ] I put 1400 kms on the bike last year topped off the petrol added stabilizer then put it on the battery tender plus .I took the bike off the tender the moddle of May and nothing but click-click from the starter solenoid. The multi meter said 13.2 volts I hit the starter button again and the power dropped right off. Yup bad cell.I informed the service dept of my problem and after a bit of mechinical banter they ordered in a new battery. I went to get it on Friday [ a 150 km trip each way ] and it was a one for one swap with a signature. [ the tag on the battery says $245.00 ouch ] Got home topped off the charge and the bike fired right up and purred like a basket of kittens [ or should I say growled ]. I then put on my MAD MAX gear and went on a test ride.Some gearbox on a GSXR 750 passed me [ on the inside ] now the chase was on . This tool was riding like an idiot but I followed at a safe distance knowing he had to stop sometime. He finally pulled over for petrol and I stopped at the next pump to give him a blast of shit for being a idiot. He got all flustered and run over to a R.C.M.P. [ Royal Canadian Mounted Police ] cruiser that was also getting some petrol. Two minutes later here comes johnny law to give me the once over. I told the constable what had transpired and he went back over wanker boy and put him in handcuffs.I came to find out the idiot had no licence / regestration / insurance and also had a outstanding warrant for beating his girlfriend and her kid. Once again BMW F800S saves the day and made Canada just a bit safer for all to enjoy.Quite a nice ride all in all.When I got back to the house the BBQ was rocking and the beer was cold! cheers!
 
#70 ·
Fit 1200gs battery

My battery failed after 11 months on a 4500km trip.Replaced under warrenty with a 1200gs battery as there were no 800 ST batteries in stock at BMW. Maybe the solution is to fit a stronger A/H battery.Bike currently has 24000 km , which should not have had battery problems.
 
#73 ·
Myk next battery will most likley be from here. http://www.shoraipower.com/s-55781-F650GS.aspx
Less weight and no lead. ( kid safe)

My kids and Grandkids never chew on my bikes so I'd forgo the 150+ dollar price tag for a weight saving. Nice that a light weight battery exists but is it really any good for the application? I've had good luck with Yuasa in the past. I imagine there are probably batteries at dealers that would work in a pinch if mine dies on the road. Doesn't have to have the official BMW blessing to make the lights go.
 
#74 ·
When my battery failed I used an old small battery from my brother. Worked fine for over a week while I sorted the replacement.
So in a pinch just about anything will do.
 
#76 ·
Not at all. Batteries should last a good few years on a bike that is regularly used. I had my last ST 3 years and never changed the battery (and the battery was older than that) - it was garaged, but never on a trickle charger. It was used once a week during the nicer months of the year and probably once a monthly during Winter.

if your battery is failing regularly you need to look at the charging system; the reg/rec is a more common fault and potentially the stator if the reg rec is tested to be fine. I would also check you have the correct size battery fitted for the ST.
 
#77 ·
Yeah, I agree with DJ123. You should get 3-5 years out of a battery unless you routinely drain it. Definitely check the charging system.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
#79 ·
Last year I was out for a ride with a couple of friends. At our half-way destination point one bike refused to restart. The rider said he probably had a duff battery as he'd had one go just like that before. Fortunately we were stopped outside a bike dealer and he went in and bought a replacement battery, leaving his failed battery behind. I tried to tell him it might not be the battery but he should also check the charging system - the bike shop could quickly do it. He insisted no, and drove home with his new battery.

I later got a message from him to say the new battery was now flat - it was his charging system all along. Another reason why I have added a voltmeter to my bike.

My bike is 6 years old and the original battery is still going strong.
Ian
 
#80 ·
I bought a new Varta agm/200cca a week before lockdown. Didn't get to install it. Got home a week ago from 3 months isolated in the country and hooked up the battery to my Oximiser. It took only a few minutes to light up green for full charge. Great.
BUT... if I'd put it in the bike then left it in the garage for those months it would have been dead for sure as this has happened a few times resulting in 5 new batteries over just 3 yrs. My riding varies between every day to occasional months of no action and this is when the problem occurs. Get to garage and no lights. Nada. Each time the sometimes nearly new battery would unrecoverable.
Fitted a new stator last year and checked the rectifier and charge voltage with engine running (14.6v). Everything seems fine. What might cause a drain on the battery when stored for a time? A mate uses his Harley about 6 times a YEAR and it always starts no problem. Hate him......
 
#83 · (Edited)
What might cause a drain on the battery when stored for a time?
The computer on board draws a tiny current all the time when the bike is 'Off'. Most modern vehicles do now a days. If I didn't ride my bike for a month (does happen), I noticed the starter would be much slower than normal. My bike lives in a shed with no mains power so I bought a cheap 1.5 Watt solar panel to keep it topped up - seems to do the job.

If you are getting 14.6v running then your stator is fine. Keep your Oximiser plugged in when you are not using the bike or you can disconnect the battery earth lead but will loose the 'Service' settings.
 
#81 ·
Also, has anyone had problems with their dipped HID draining the battery? I will check the charge voltage, engine running again when I install this new battery. The voltage stated above was each time I installed a new one and the HID has been there all along. Frankly don't need a main beam at all with a dipped hid unit.
 
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