Voltage regulator replacement or Modification - 04 1100S

[Oldrider51]

I have seen a lot of discussion about replacing the voltage regulator or modifying on older RTs to get a higher outlet voltage for the newer AGM batteries and want to do the same to my 2004 R1100S with ABS. Has anyone done this and is it as complicated as doing the RTs? Does the ABS module need to be removed or can one maybe just removed the ECU above the alternator? Any assistance or guidance in this matter would be appreciated? 

[AndyS]

I find this an interesting topic inasmuch as I don't understand the need for it. 

On my 2003 1150RT I was running an Odyssey battery for years and had no issues.

I'll wait for Roger and DR to come along and tell me why I'm wrong, but it looks like a solution looking for a problem.

[dirtrider]

18 hours ago, 041100S said:

I have seen a lot of discussion about replacing the voltage regulator or modifying on older RTs to get a higher outlet voltage for the newer AGM batteries and want to do the same to my 2004 R1100S with ABS. Has anyone done this and is it as complicated as doing the RTs? Does the ABS module need to be removed or can one maybe just removed the ECU above the alternator? Any assistance or guidance in this matter would be appreciated? 

 

Morning 041100S

 

Like Andy I ran the Odyssey AGM for years (in a few different BMW 1100/1150 motorcycles) with the stock voltage regulator.

 

It worked OK  & while the Odyssey battery probably never reached 100% SOC I didn't have any starting issues or early battery failures. 

 

Not all AGM batteries require the same higher charging voltage, most do require (or suggested anyhow) a higher charging voltage, with the Odyssey  AGM being at or near the top of the charging voltage requirement. 

(check with your battery supplier for charging info on the AGM brand that you intend to use, ask about charging voltage required  at nominal working temperature to keep it fully charged)

 

As far as how to change your regulator?-- Good question, the BMW manual requires the engine front cover (not just belt cover but entire alternator-mounting engine front cover be removed). Most do not do it this way as it will come out the rear with enough parts removal --Motronic & ABS module, etc-- (some have been able to fool around & move the ABS module enough to get the alternator out).  

 

Or you have the option of just unbolting the alternator rear cover then working under the cover  by (removing 3 screws then spinning it around)  to sort of access the regulator (it has been done this way on the early 1100S but I'm not sure on the later 03/04 S bikes (still takes Motronic removal I'm pretty sure).

 

If you want to try the cover removal method look for an old post from  "Lowndes" https://www.bmwsporttouring.com/topic/88369-r1100s-alternator-removal/

 

You also have other options, like unbolting some of the R/H side  frame work as that allows better access to get the alternator out without removing the ABS module.  

 

I wish I was more help but on the few 1100S alternators that I have removed they were earlier 1100S bikes, plus  I can't remember ever doing JUST an alternator removal without something else also being done so the bike was usually 'much' father apart than just the alternator area. 

[roger 04 rt]

DR’s comment that he’s run without boosting the voltage is fair but Andy’s comment (which almost always right on) that it’s a solution looking for a problem is not on target. It is fairly easy to sulfate an AGM battery, I’ve seen it happen three times: my 2004 R1150RT (less than 2 years to sulfate), my 2001 R1150GS (5 years or so), my neighbor’s aircraft which has Odyssey standby batteries for navigation (about 4 years to 50% state of health, and the battery assembly is $1500!).

 

The common denominator seems to be partial discharge and recharge at a low voltage. Both the bikes and plane had 14V (28V) regulators which in practice means they run around 13.7-13.8V because they are temperature compensated to reduce the changing voltage as temperature increases and they are warmed by the engine and ambient temperatures. I’ve received GS-911 data from Singapore and seen charging at 13.6 V. The fastest way to sulfate an Odyssey Battery is to frequently make short trips, and connect a Battery Tender Jr. when you return.

 

At 70F, the Odyssey batteries like about 14.7V, other AGM batteries are happy at 14.4V charging voltage. Solutions are to change the voltage regulator, to put the bike on an Odyssey-approved charger, or to not worry about how quickly your bike starts or how often you replace the battery.

 

 

[Oldrider51]

Thanks to dirtrider and roger 04 rt, 

Did not mention that the current battery is an Odyssey PC680, and also that it is the second one. The first one died about 2 years ago after 3 years of use and using a Battery Tender on it. Now I use a CTEK charger that is for AGM and temperature compensated. Normally I tried to ride the bike a minimum of 20 miles when I take it out, but this still concerns me and I have not had problems when on longer trips (over 500 miles). I thought about getting the regulator from Euromotoelectrics.com but they state an output of 14.5 which still may not be high enough. Need to look back on the post of adding the diode. I also need to check the current charging voltage just to be sure what it actually is. Will look into what it might take to do this modification. Again, thanks 

[Mrclubike]

I have a Odyssey that has been on a steady diet of 14.7 in an R65 (it has a Delco regulator with an "A" circuit conversion to get the voltage up)

It is still going strong after 5 years

So I decided to do the Diode modification  my R1150R reg 

I ended up with a charging voltage of around 14.9

I  was   worried that it  was a little to high  so I installed a 14.5  reg from EME (not the best but better than the 14 volts of the stock)

I was more worried about the effect of 14.9 volts on the bike than the battery

 I forgot  about the temperature compensation so the higher voltage may have been due to the temp being around 45 F

So I may put the modified reg back in when it warms up and see what voltage I get

 

 I did not get a exact NTE5812 so I got the equivalent 6amp 100 volt

It looks to be the same form factor so I assumed  it was the same

I have a hand full of these diodes so I may be able to hand select one with a lesser  voltage drop and install it. Not sure it will help bring the voltage down a tiny bit or not

What do you think Roger

 

I have an R1150R without ABS

So the reg is removable with out removing the gen from the bike but it still is a pain to get it in and out

Also I had to mount the diode closer to the brushes than Roger did on his to get it to fit inside the reg

 

This first picture is the Delco reg in my Airhead

I thought about doing this to my R1150R

 

[roger 04 rt]

You might be able to hand select for a higher voltage but I doubt it will vary by more that 50 mV. Personally I haven’t worried about the higher voltage but there is a voltage that will be too high and I don’t know what that is. 16V Being too high rings a bell but I don’t have any data behind that.

 

On the other hand, the 14.5 V regulator is a big improvement and I’d be satisfied with it too. My objective was to get out of the know bad range.

 

I'm working on a standby battery project using Enersys Cyclon cells (same technology as the PC680) and they have very specific language warning about the rapid damage that occurs at less than 2.45V for charging a 2V cell (14.7V for a 12V cell). In this application there is a Schottky diode in series with a 28V charging system so the effective voltage presently is about 27.5V versus 29.4V required by the batteries. And that did certainly, prematurely, damage the battery. I’ll fix it with a proper external charger.