Battery Life

[hooah54]

I am on my fourth battery on my 03 r1150R. I have had two OEM batteries and two Westco from the boneyard. The OEM and Westco have lasted less than three years. All of the batteries have been on a Battery Tender. The last Westco was doing well for the last two years then took it on a 170 mile trip, topped off the tank, turn the key and all kinds of wonky electrical issues...tach sticking at 7K with engine not running, speedo wobbling, all instrument lights flashing...are there alternator issues here? New OEM battery and did 300 miles on it ...confused

[captaincable]

Skip using a battery tender unless you only use it for 2-3 days at a time I am convinced they are bad for your battery if left on continually, I just use a regular charger occasionally ( every month or so usually more if not in use ) Have talked to a lot of people over the years that have had very short battery life and used tenders . Maybe its just coincidence but if you use chargers as I mentioned above willing bet you your batteries will last longer . Having said that there are other things that could be loading your battery or just not charging right when running. I still have battery from a R850R that was replaced by P.O. thinking it was a bad battery turns out it was just a slow turning starter, that was 3 years ago + its has been charged maybe four to six times in those three years and i checked it a week or two ago and it was approx. 12.9 vdc the same with a marine battery that is 4-5 years old still and it gets charged even less still works fine.
I know a lot of people have had good luck with tenders , the above are just my observations.
Mike

[AZBMWRIDER]

Do you reside in a hot weather climate ???

[Roger 04 rt]

It sounds like you have a few possible issues from the symptoms:


--Your starter may need service. There is an internal grease cover that can drop into the armature causing instant flakiness of electrical. Then after some metal arcs away from the cover and then it's alright for a whil

--Your HES is breaking down, this sometimes causes the flaky reading of your tachometer.

--AGM batteries do not like being charged by a Battery Tender Jr. Its output is around 13V, about a volt too low as a trickle charger.

I've only realized these issues after painfully debugging them on mine: http://bmwsporttouring.com/ubbthreads/u ... 202&page=8. Start at the last post on the page and read what interests you.

[Roger 04 rt]

Here's some good info on the Valeo starter: http://forums.bmwmoa.org/showthread.php ... of-Failure.

[sjbmw]

Year ago, when I went to buy a trickle charger, I was advised to spend the extra $50 and get the BMW OEM one, as the Battery Tender (and BT Jr.) will cause problems.

[hooah54]

Yes I reside in SC where the summers can be brutally hot and humid.. I am using a battery tender and replaced the starter a few years ago.

[AZBMWRIDER]

With the odd, electrical issues you saw, I'd check the grounds on the electrical system for security and corrosion .
Have you checked the voltage with the engine running at higher speeds than idle ?
You should be seeing above 14 volts with a fully charged battery .