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1st discharge: 12.4 Ah, 78% capacity, 4 hours 30 minutes
2nd discharge: 14.8 Ah, 92% capacity, 5:20
3rd discharge: 14.8 Ah, 92% capacity, 5:20

The third discharge cycle was just the same as the second. I may have reached maximum reconditioning. At 92% capacity, there's still more life in this battery according to Odyssey, who says to replace at 80%.

I wanted to get out for a ride so after the third discharge the battery I set the charger for a 10 amp rate for an hour. To my surprise with only a 60% charge, it fired quickly with no ABS error. Tomorrow morning, I'll run a cold start test with the GS-911 and see what the battery drop is like compared to pre-conditioning.
 
After three discharge/recharge cycles following Odyssey's instructions for how to desulfate the PC680 in order to regain its lost capacity, the GS-911 Wifi was used to collect a start-up voltage data set this morning. In its fastest mode, the GS-911 captures battery voltage and RPM data every 325 mS (about three samples per second), something that can't be done with ordinary shop tools or a regular DVM.

My R1150GS now starts in under a second after an overnight cool-down period, and the minimum transient voltage is about 10V, up from 8V prior to reconditioning. Battery capacity improved about 20%, increasing to 92%, compared to 78% prior to reconditioning. The ABS no longer logs an error at start-up, compared to several errors before. The steady state cranking voltage (fuel pump relay removed) has improved about a quarter volt, now at about 10.6V compared to 10.3 V before.

The main lesson learned here (as I did on the RT) is that it's not too hard to damage the PC680 by improperly charging it. Even with a boosted voltage regulator, this battery was sulfated by a non-approved charger, which ran only 6 hours per week, for about 6 months.

All in all, the results look good, a success. It'll be interesting to see how many more years I get from this battery. In the future, since the PC680 has a low self-discharge rate, I'm thinking that I'll remove the battery for the winter, use no battery maintainer, and recharge it when the bike comes out of storage.

Below are the before and after charts showing the significantly improved voltage response to starting.

Screen Shot 2019-08-10 at 9.17.02 AM.png

Screen Shot 2019-08-10 at 9.17.33 AM.png
 
Roger, after all this, what battery maintainer would work the best for the PC680 if an owner wanted to just hook up a battery for the off-season and “catch it in the spring”?
OM
 
Gary, I’m not sure which one is best. I’d look over the specs and make sure the maintenance voltage is 13.7 +/-. Odyssey has a list of approved chargers on their site.
 
Is there a max current specified for recharging Roger? Just wondering if current limiting should be applied when doing constant voltage charging. Your posts have me thinking about a winter maintenance project for my Odyssey batteries. :thumb
 
You guys and your Oddity (oops, Odyssey) batteries. :)

I've run cheap and unsophisticated AGM batteries for the last 10 years, have never had an issue, and the one I put in 9 years ago is still going strong. Somehow, I feel diminished in the presence of all this high-end info - but my wallet is thicker! :D

Just kidding about feeling diminished. Lots of good information for those who can use it, guys. :thumb
 
You guys and your Oddity (oops, Odyssey) batteries. :)

I've run cheap and unsophisticated AGM batteries for the last 10 years, have never had an issue, and the one I put in 9 years ago is still going strong. Somehow, I feel diminished in the presence of all this high-end info - but my wallet is thicker! :D

Just kidding about feeling diminished. Lots of good information for those who can use it, guys. :thumb

Methinks you just jinxed yourself :eek
OM
 
You guys and your Oddity (oops, Odyssey) batteries. :)

I've run cheap and unsophisticated AGM batteries for the last 10 years, have never had an issue, and the one I put in 9 years ago is still going strong. Somehow, I feel diminished in the presence of all this high-end info - but my wallet is thicker! :D

Just kidding about feeling diminished. Lots of good information for those who can use it, guys. :thumb

First Odyssey I bought was in June 2010. It's still in the RT so over 9 years now. Second one installed in my G/S in 2012 and also still in the bike. So pretty good luck so far but I must admit the Panasonic SLA in my RS lasted over 10 years. I bought another just like it in 2017 and installed it before a cross country ride to PA and back but the old battery is now running my shed winch and still works perfectly. Now that a digital voltage regulator for airheads is available and inexpensive it makes running an Odyssey at the correct charging voltage really easy. These are really tough mil spec batteries and are ideal for bikes.
 
Is there a max current specified for recharging Roger? Just wondering if current limiting should be applied when doing constant voltage charging. Your posts have me thinking about a winter maintenance project for my Odyssey batteries. :thumb

None mentioned in the Odyssey technical info. I think the bike’s alternator could source 40-50 amps. My experience is that the better conditioned the battery is, the greater the current they absorb initially. On my bike within about an hour the charging current was under 10 amps.

Roger, after all this, what battery maintainer would work the best for the PC680 if an owner wanted to just hook up a battery for the off-season and “catch it in the spring”?
OM

This also from Odyssey:

”For seasonal applications (non-daily use applications that set for more than 3 days in a row frequently) regular use of an approved maintainer that meets the charge voltage requirements noted in the previous paragraph is highly recommended during the season and/or a disconnect switch.The preferred storage method is to fully charge the battery before storing and disconnect the battery from the application (shelf storage mode). Stored in or out of the application with no loads, the battery would not require charging for up to 2 years at 77°F or until it reaches 12.0V, whichever comes first.”
 
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Good, detailed information Roger :thumb
“Tags” for the “Tag Cloud” have been added for easy searching.
Gary
 
You guys and your Oddity (oops, Odyssey) batteries. :)

I've run cheap and unsophisticated AGM batteries for the last 10 years, have never had an issue, and the one I put in 9 years ago is still going strong. Somehow, I feel diminished in the presence of all this high-end info - but my wallet is thicker! :D

Just kidding about feeling diminished. Lots of good information for those who can use it, guys. :thumb

No volts for you - 1 year.
 
Last week, I started to see the same behavior that I reported at the start of the thread: ABS errors and dips in the starting voltage. The battery seems fine, as it did at the beginning, and the bike cranked well too. I considered trying reconditioning one more time but ran out of energy for the project. I bought and installed a new PC680, which will be a good match with the Vreg mod to 14.6V and my AGM charger.

After I installed the new battery, I called Odyssey to ask how to identify the manufacturing date. It's the 4 digit code in the white box, on top of the battery. The code is 1111 which means November 2011. I had thought I was working on a 4-5 year old battery that turned out to be nearly 8 years old. For the first 6 years it was charged at a low voltage, so I'd say 8 years is pretty good lifetime.

E7E43E28-5956-42EE-96FA-99320D3D988F.jpg

Here is the plot of starting with the new battery. Note that it dips to about 10.6V for a few hundred milliseconds and then cranks at 11V--much better than the reconditioned results from earlier in the thread. I've added this graph so that others have it as a reference point. Early in the thread you can see my sulfated battery, middle of the thread an 8 year-old reconditioned battery and below, a new PC680.

Bottom line: the problems were the battery, the starter is fine

E568B2DA-D199-4399-A359-731082501F74.jpeg
 
Manners

Routinely, I get called worse and I have never apologized for it. That make me bad man being Canadian and all.

Spreadsheets are just a way to collect and organize data for dissemination. I hate them. I call them the "devil's method of keeping me from doing my job." I have a lot of spreadsheets.

Last time I checked, a scan tool and a spreadsheet don't have jumper cables to get you home.

Demonstrating how smart you think you are, generally, po's those that know you aren't.

If you are allowed to come to Canada and your car won't start at -40C, you gonna create a spreadsheet and hook up a scan tool or you gonna go KISS?

Many of us wouldn't have the "common sense" to diagnose our computer equipped Oilhead's without Roger's contributions here and BMWRT.com in the past. I've sent him many data logs over the years and he's been nothing short of a God in terms of his free time and advice.

Get some manners sir. You're giving BMW riders a bad name.
RPGR90s
 
Hello Roger,

I currently have a pair of 01 R1150GS's. what is the Vreg mod to be done to aid in maintaining the PC680? I use a noco genius 7.2 amp to maintain at home and it seems to be doing well.
recently have had to reset plunger failed a couple of times on one bike with a less than 1 year old PC680.

Thanks, Rick
 
VR upgrade

Hello Roger,

I currently have a pair of 01 R1150GS's. what is the Vreg mod to be done to aid in maintaining the PC680? I use a noco genius 7.2 amp to maintain at home and it seems to be doing well.
recently have had to reset plunger failed a couple of times on one bike with a less than 1 year old PC680.

Thanks, Rick

This is the one I installed a few months ago.
https://www.euromotoelectrics.com/BOSCH-Voltage-Regulator-BMW-R-K-p/boalt-reg365.htm

RPGR90s
 
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