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Starter or Battery 2004 R1150RT

The other annoying thing on the wiring is that the lights come on before the motorcycle starts, draining a weak battery.

That one is easy. On all my power sports equipment that have an oil light, I piggy back a wire on to the switch and use the oil pressure switch to close the ground side of the the relay. I use the power side of the headlight for the positive side of the coil and and then just connect the power side of the headlight to the load side of the headlight.

Headlight doesn't come on until you have oil pressure. That's an old Murphy switch trick.

It's easy, it doesn't backfeed the oil light. I've done it numerous times on machines that need all the help they can get starting, like my quad I use for plowing snow.

When I hit "stuff" with the plow, I generally stall it and by the time I fix the "stuff" I just hit to cause the quad to quit, there is just enough battery to crank it over once or twice. With no headlight on, I get twice and on a good day, almost three times.

I did it on my R1100RT, my Kawasaki, a few of my friends' bikes and haven't had an issue yet.
 
After getting Odyssey's advice on how to best maintain their batteries when installed in a bike whose charging voltage is in the 13.6-14.0 volt range, like the R1100s and R1150s, this morning I discharged my battery by about 1 aH, roughly a 5% discharge.

Next, the battery was recharged at 13.6 volts, simulating an Oilhead alternator. The initial current was 3.6 amps and after an hour it was drawing 1/10 amp and it appeared to be recharged.

At that point the recharger was adjusted to the recommended 14.5 volts and the battery drew about 1 amp, indicating that it was not fully charged. It took another half hour to finish charging the battery at 14.5 volts, I don't know how long it might have taken had I left the charger voltage at 13.6V since the charging current was under a hundred milliamps at that point.

Then to finish this process up, I discharded the battery by 5% a second time and recharged it at 14.5V. Initial current was 4.6 amps and it took 40 minutes to reach 100% State of Charge (SOC).

In order to reach a 100% SOC after a 5% discharge it looks like Odyssey is giving good advice: either charge at 14.5 volts or charge the battery at 13.6-13.8 volts for an extended period of time (several hours).
RB
 
I performed a discharge cycle again and recorded 7hrs 35minutes to 10.02v when the load was still 3.7amps (on my PC925). In going back to the Odyssey manual(s), that is actually right in line with recomended capacity. Although a slight improvement from the first test, its not dramatic, hence I believe my bike charging system is fine as is. I am however looking at upgrading my battery charger as mine is rather low tech.
A question for GSAddict - if you've been increasing the voltage (as per the procedure Roger depicted) for years on your bikes, what if anything has been the effect on bulb life? Seems you're "real life" experience and answer might help diffuse that potential or suggested draw back that looms large for this consideration.
 
Quick question: are you using a resistor for the load test, if you are, what's the value? I agree that your battery looks close to 100%. The 5 hour discharge rate for testing is 5.6A which is 26 aH. The 8 hour rate is 3.4 amps, 27.2 aH. http://www.odysseybattery.com/documents/US-ODY-TM-001_0411_000.pdf.

When I measured mine I recorded the voltage every half hour, calculated the average voltage between points. Used that divided by the resistance as the load. This done so that I could adjust current as voltage declined.
RB
 
I used an automotive 50w halogen lamp that measured 3.77amps after a period of time being on. One thing I didn't do was measure that value at the end of the test & not sure that might skew accuracy?
 
With that added info. I'm thinking the average current through the discharge interval was 3.3 amps which means you got about 23 aH or 85% SOC. IT took me till the 4th time to get a gain.

A key is the recharge is full current, whatever the battery will take at least 40% of 27aH about 11A.
RB
 
Well, may as well run another test cycle then as a trend may not have completed yet. My charger doesn't have the proper technology, even while having an AGM setting. Problem is that the 10amp output settles off to a couple of amps way quick in the procedure and I'm finishing with a power supply that pushes voltage up to 15.5 but has small current rating (divulging that, probably going to draw fresh ire) Definately not as text book as your procedures, but on the gift forfront, a new charger is a reasonable development.:idea
 
Before I got a high enough power charger, I connected jumpers from my SUV with an ammeter in series. Once the current was flowing I started the car. Although not a high voltage it was over 14 and the current remained high for an hour. Then I reverted to the lower power. That was my battery's first step of recovery.
 
A question for GSAddict - if you've been increasing the voltage (as per the procedure Roger depicted) for years on your bikes, what if anything has been the effect on bulb life? Seems you're "real life" experience and answer might help diffuse that potential or suggested draw back that looms large for this consideration.

I have had no abnormal lamp failure rates that were apparent in the 4 years of incandescent only.
That being said, about 3 years ago I changed the entire bike over to LED & HID with the exception of the high beam and telltale lamps. I have changed 1 high beam lamp in that time.
 
Starter problem: My Saga!

Roger, In august of this past year I had a similar issue with my 04 R1150GS. I at first thought it was the Battery and replaced the old one with a new gel. It ran great but became nearly impossible to start acting as if it lacked spark or fuel. After further testing it was found that it had intermittent spark and fuel. after a few weeks I surrendered and took it to the dealership. After six weeks a new HES sensor, trading out the control module ( after not working both parts were absorbed by myself and the dealer) and $1000.00 in labor expenses the dealership ( with my help on a saturday afternoon) figured out that the problem was the starter. The starter was slightly laboring which robbed too many volts from from the fuel and ignition system. One of those expensive silly, simple,stupid $225 fixes (cost of a new starter on-line) that even had the dealership scratching their heads.
 
For the past three weeks I've been monitoring my starts now that the battery stays at a 100% SOC (state of charge). It takes about 1 second, a little more or less. A couple days ago I cold-soaked the bike to 25F. The battery voltage dropped with temperature to 12.7 volts (from 12.9V).

With the fast idle lever in mid position, transmission in neutral so that the starter was also turning the transmission input shaft in the very cold transmission oil, the engine was up and running in 1.4 seconds. Not bad.
 
Here's some further information on charging AGM batteries.

Although BMW has shipped GEL batteries on its motorcycles, for many years, they have shipped AGM batteries on the R1200GSA from 2006 to present, and on the new R1200GSW too.

That being the case I asked Terry who runs a 2010 R1200GSA (and incidentally has dual LC-1s installed) to collect some more data on his bike's charging system. He obliged and took battery voltage data with his GS-911 and also measured the voltage with his Fluke DVM. The GS-911 and Fluke seem to be within 50-100mV of each other so I believe the results are a good representation of what's going on.

Here are the results of Terry's measurements from the GS-911:
Ambient Temperature: 55-60F
Charging voltage cold, right after starting: 14.85V
Charging voltage warm: 14.7V
Charging voltage hot: 14.6V

At higher ambient temperatures the voltage will come down a bit further but the bottom line is that, like Odysset for its AGM batteries, BMW charges AGM batteries at a higher voltage than GEL or conventional.
 
Here are the results of Terry's measurements from the GS-911:
Ambient Temperature: 55-60F
Charging voltage cold, right after starting: 14.85V
Charging voltage warm: 14.7V
Charging voltage hot: 14.6V

This is with an original and stock alternator/voltage regulator in his GS?
 
Yes, Teery's bike has the original stock alternator and regulator. Interestingly, the maxbmw parts fiche shows that the 1200GSA has an AGM battery and a DENSO alternator. Bikes with the gel battery seem to use a Bosch alternator. I don't know the reason for the alternator difference. Could be power, could be charging voltage.
 
I don't know the reason for the alternator difference. Could be power, could be charging voltage.

The voltage regulator is what matters when it comes to matching the alternator/voltage regulator to the type of battery.

I wonder if BMW would do that without (maybe they do) stating in the owner's manual that a standard FLA battery cannot be installed. You'd overcharge it big time. The voltage regulator in my R1150 GSA regulates at 14.2V.

Even so, those voltages are a bit high according to this AGM charge table. Of course there can always be slight variances from manufacturer with specialty batteries.
 
The voltage regulator is what matters when it comes to matching the alternator/voltage regulator to the type of battery.

I wonder if BMW would do that without (maybe they do) stating in the owner's manual that a standard FLA battery cannot be installed. You'd overcharge it big time. The voltage regulator in my R1150 GSA regulates at 14.2V.

Even so, those voltages are a bit high according to this AGM charge table. Of course there can always be slight variances from manufacturer with specialty batteries.

Certainly, it is the voltage regulator that matters. I'll ask Terry if there is any warning language on his motorcycle or in the manual he has. Whether they have the language or not though my point is that BMW uses an appropriately higher charging voltage when they install an AGM battery.

Your 1150GSA and my 1150RT use the same voltage regulator which is a Bosch unit marked 14V. When the engine has warmed up, the ones I've measured are between 13.6 and 13.9 volts, depending on temperature.
RB
 
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Your 1150GSA and my 1150RT use the same voltage regulator which is a Bosch unit marked 14V. When the engine has warmed up, the ones I've measured are between 13.6 and 13.9 volts, depending on temperature.
RB

This has been my experience as well, never seen one over 14.0v
 
...my point is that BMW uses an appropriately higher charging voltage when they install an AGM battery.

That may be the case. I could only confirm that if I had the voltage regulator specs or the Denso voltage regulator part number and also the battery manufacturer name and model.

And that "higher charging voltage" might be appropriate for a particular AGM battery; certainly not all AGM batteries. You are always better off slightly undercharging a VRLA battery than slightly overcharging it.


Your 1150GSA and my 1150RT use the same voltage regulator which is a Bosch unit marked 14V. When the engine has warmed up, the ones I've measured are between 13.6 and 13.9 volts, depending on temperature.
RB

They are always marked 50A 14V or 70A 14V.

The VR in our motorcycles has a Vreg of 14.2V and sure enough, that is the most I have seen on my calibrated voltage display that is connected directly to the battery. Most of the time it is between 14.0 and 14.1V with a rare 13.9V when hot.

In my cars and other motorcycles, I stick to good old FLA type batteries. They last much longer given some periodic maintenance.
 
Here's what I've got from a collection of different R1150s.

R1150RT: 32F 13.76V average
R1150RT: 75F 13.83V av.
R1150GS: 68F 13.72V av.
R1150RT: 60F 13.62V av.
R1150GS: 68F 13.88V av.
 
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