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Starter or Battery 2004 R1150RT

Ran a 5th discharge cycle today. Believe that I have maxed-out the recovery at 90% of total amp-hours. Odyssey says that if you don't get 80%, replace the battery!

It looks like due to under-charging my 16 aH PC680 is now a 14.4 aH battery. At least that's up from about 11 aH when I began reconditioning it. Charging overnight I'll try a cold start in the morning.

RB
 
This is a very informative thread and I Just want to confirm I have the correct "take a ways":

First, conventional battery chargers and tenders will damage an AGM battery if used over an extended period of time. A temperature compensated AGM charger should be used if an AGM batterties requires recharging.

Second, since AGM batteries have a long storage life, a battery tender is not needed for winter stoage if the battery is fully charged and all current draws are eliminated.

Since I really don't want to pull the fairings on my 03' RT to disconnect the AGM battery, is there any other "key off" current draw besides the RID?

Thanks
 
You do know what the acronym "AGM" is?

You do know what the acronym "AGM" is? It's not magically scientifically like.
 
This is a very informative thread and I Just want to confirm I have the correct "take a ways":

First, conventional battery chargers and tenders will damage an AGM battery if used over an extended period of time. A temperature compensated AGM charger should be used if an AGM batterties requires recharging.

Second, since AGM batteries have a long storage life, a battery tender is not needed for winter stoage if the battery is fully charged and all current draws are eliminated.

Since I really don't want to pull the fairings on my 03' RT to disconnect the AGM battery, is there any other "key off" current draw besides the RID?

Thanks

I can't say for sure that it applies to all AGM batteries but what you've outlined is what Odyssey says about the batteries they make. They also say that in the "bulk" charge model charging current for the pc680 should be greater than 6 amps. (I'm getting a manual-style charger which will double as a power source for more sensitivity test. Then I'll put my Odyssey charger onto the flea market. AD IN FLEA MARKET.)

The key-off connections are: RID, MOTRONIC, ABS, and Flasher Relay. In another thread someone (GSAddict I believe) said a couple milliamps. If that's the case you would lose 2 aH per 8 weeks.

RB
 
Just finished a 6th discharge cycle. The PC680 delivered a full 16 amp-hours.

It looks like with enough charge/discharge, and with the correct charger, the pc680 can be brought back to full performance. It seems like 2 days on the odyssey charger did the trick. It now has 50% more capacity than when I began charge/discharge a couple weeks ago.

Will run another cold start cycle tomorrow. Things are looking good.
RB
 
Well as far as the starting issue goes, it seems to be wrapped up. I took a full set of 40F cold-start data: GS-911 and LC-1. A strong, properly charged PC680 what what it needed.

The battery voltage when I pressed the Start Button dropped to 10.4V, compared to 7-8V when I started the project.

From the time the starter button was pressed until the time the motor reached 1150 RPM was somewhere between 0.75 and 0.95 seconds.

All the sensors are well-behaved, particularly Spark Advance, Dwell and Injection time.

The AFR chart moves smoothly to its various after-start and warm-up enrichments and is well behaved. A second battery would probably make it a little stronger but that would be a project for another time.

So when I get some time I'll add the diode to the alternator so that I don't have to use the charger so often to finish charging the battery after short rides.

You gotta love the PC680, I undercharged it for a year and it's come back 100%.

RB
 
A friend with a 1996 R1100RT saw this thread and decided to run an amp-hr test on his 6 month-old PC680 battery. It came up just short of 10 aH. At the 2 amp rate of discharge this means the battery was just below 2/3 charged even though the OCV (open circuit voltage) was 12.9V which would indicate fully charged.

It will be interesting to see how much capacity he can recover using the Odyssey recharge procedure.
RB
 
Just before opening my bike up so that I can add a diode to the regulator (a nasty job, with lots of stuff to remove), on a hunch, I tried starting after a cold-soak with the BoosterPlug disconnected. I only tried it once but it seemed to start quicker, a bit.

With the BoosterPlug attached, the Motronic sees air temperature 36 degrees colder than oil temperature. In my case it was 40F at the oil, and 4F at the air temp with the BP. It seems possible to me that it sees those unequal temps as a sign that the bike has not cold-soaked. In other words that the bike's oil isn't fully cooled off--a sheer speculative comment in my part.

What I can say with certainty is that the injection pulse at start was a little longer without the BP.

Curious.

RB
 
That's pretty interesting Roger. I wonder if you've found a side effect of the booster plug or if this behaviour is intentionally programmed in the firmware. I wish a Motronic software engineer would go rogue and fill us in. :D
 
Getting the ABS out isn't really a bad job but to get to the voltage regulator you've got to:
--remove left and right fairings and fuel tank
--remove Motronic
--remove ABS
--I chose to pull the battery

Still not sure I can get to the vreg without
--remove alt belt cover
--remove belt
--remove alternator

Then add a diode, a couple bucks. This is a lot of work for the PC680 battery ...

If I pull the alternator, I have a spare HES so I'll replace it. I'm this far maybe I just will.

The other thing I could do is pull the throttle cable and Bowden box to get the battery/ABS box out. That would let me swap the 3 bar regulator for a 3.5 I have. Maybe that's over my time limit.
RB
 
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I got to the "diode" project over the weekend. The alternator is now charging at 14.75 volts. Many thanks to GSAddict for his valuable help, often on a moment's notice at the crack of dawn.

While the project seems a success, it is a bear of a job. At this point I can't say for certain that it won't be bad for the bulbs, or other electronics. Nor do I know for sure that the higher voltage won't be bad for the ABS or Motronic. I don't know that I've selected the best diode, and I don't know how long the diode will last. If the diode fails, the alternator will stop charging. (But often overloaded diodes short out in which case the alternator will operate but at its original voltage.)

The first time I reassembled, the diode interfered with the alternator body causing two internal pins on the voltage regulator to touch. This happened because I attempted to do the work without pulling the alternator. You really have to remove the alternator to do a good job, which I did the second time. (It would be better to find a voltage regulator that was adjustable or a higher voltage, then swap regulators. I haven't found one yet.) Removal of the ABS system takes a great deal of care.

RB

If I haven't scared you off from trying, and you're willing to take all the risk yourself, and you want to install a diode, here is a brief outline of what I did:

Step 1
Remove the alternator by removing:
-Seats, left and right fairing and fuel tank
-Alternator Belt Cover
-Battery
-ABS (requires bleeding all circuits afterward)
-Motronic

vreg%201.jpg


Step 2
Remove the Voltage Regulator from the Alternator by:
-Removing the black cover on the alternator

And then:
-Drill out the spot weld on the ground lug
-CAREFULLY remove Ground Lug. (Note in the photo below that I have started removing the ground and it is bent upward.)
-Save ground lug to shim the underside of the regulator when you reinstall it.

vreg2.jpg


Step 3
Boost the Voltage by Adding:
-One NTE 5812 Diode in series with the internal ground
-Reinstall Vreg
-Reinstall Alternator
-Reinstall fuel tank and battery
-Test alternator output

vreg3.jpg


Step 4
-Pull fuel tank and battery again
-Reinstall and Bleed ABS system
-Reinstall everything else

There are a lot of steps and skills needed for this project. It would be easy to do it wrong and cause serious damage. This outline and the photos should be sufficient if you have the right skill set to take this on. Otherwise, if you have an Odyssey PC680 battery and want to keep it 100% charged, consider charging your battery with an approved Odyssey charger every few weeks. Or at your next battery change consider a regular lead acid or Gel battery, both of which are fully charged with the standard alternator.
 
Nice work, easy pathway to follow, despite the locations and challenges.

You've presented a strong case for others to investigate the "happiness" of their AGM's, so I am going to test mine. Although it has an open circuit voltage of 12.9 since removal this fall, I had previously reduced my alternator output to 13.8v subsequent to concerns on overcharge from my HO modified charging system (900W) where an ambitious internal regulator was pushing values north of 14.5v (was probably on the eve of failing I suspect).
Being a PC925, the numbers are substantially higher, and I dare say all the rules are bent somewhat, with 380CCA's plus a voltage correction table that allows for normal fueling on crank even when the battery might drop off.
Regardless, if the slow drain test confirms less than full capacity I'll look into raising the voltage again. And yes, the 925 is somewhat of a monster (26lbs compared to 15.4 for the 680) but I wanted a longer rating for the tuning/ logging lap top I carry occasionally, and she actually fits nicely in the standard tray with stock tool kit on top.
 
It will be interesting to hear how many amp-hours you get on the first discharge cycle. Once you get to 11.2 volts it drops very quickly to 10.2.
 
The alternator is installed and the belt tensioned, the ABS reinstalled and all the brake circuits bled (side benefit, my front and rear brakes are firmer). I've reinstalled the add-on pressure regulator but removed the BoosterPlug. The fuel tank and all the plastic parts went back on too. The battery had been disconnected during surgery so it was charged to 100%. As a result of the disconnect the Motronic was reset, so I did the twist-the-throttle thing.

With everything back on and the bike cold-soaked in my garage, I ran a cold-start test. Fast idle lever to mid-dent, press the button, Er, er, vroom--1.5 seconds to start and the idle jumped immediately to 1400 RPM with a stable spark advance and dwell. Just what I was hoping for when I started the thread.

The bottom line to this whole exercise: a bad lower plug, weak stick coils and a 67% charged, sulfated Odyssey PC680. The battery was restored with 6 Odyssey specified discharge cycles and the alternator output boosted by about 0.7 volts with the addition of a diode in the alternator's voltage regulator. I will charge it as needed with an odyssey approved charger.
RB
 
Dropping quickly subsequent to 11.2V an understatement!

I choose to initiate the first discharge test a bit late in the day and ended up having to stay up later than intended (& tending to want test to end LOL) to capture the "10.2V" moment.
As you say, the time to get down to 10.2 from 11.2 was rather exponentially quicker than the previous decay behaviour. I utilized a 3.7amp load and found this first test took 7hrs. For the PC925 that is I believe not up to snuff but I'll perform the additional drain/recharge cycles to document changes in capacity.
One thing that looms large relative to this 925 history, I had "accidentally" allowed this battery to decay to a shockingly low state last winter when I guess my storage temps were too high and it was still connected ( and again I hadn't really reviewed or learned all the details on this when I bought this first to the bike AGM item). If I remember correctly, it was down below 8v, took a recharge rather well and I have not been having any issues starting (cranking behaviour is stellar, as well I have voltage correction tables adjusted to satisfy cranking fueling etc.). Guess we'll see.
Lorne.
 
While contributing to the ABS thread (here) I noticed that the GS-911 reports battery voltage and the voltage at the top of the coils VIGN.

VBAT is 14.56 volts and VIGN is reported as 13.8 volts. That's a pretty big drop across the key. I think I'm beginning to see why they added the second Load relay to later R1150RTs.

motronic2.4status.jpg
 
Here is what Odyssey says for maintaining a PC680 or other Odyssey AGM battery if your alternator voltage is below 14.5 volts, for example an R1150 which has a 14V regulator that outputs about 13.7 volts much of the time.


The recommendation would be proper consistent charge maintenance when the motorcycle is not in use with an ODYSSEY program approved 12V charger/maintainer from the list of approved chargers linked on the ODYSSEY website Product Support page. Any of the listed maintainer chargers can be used to maintain the battery indefinitely without harming the battery.

We would also recommend turning the headlamp on for 1-2 minutes after parking the motorcycle but before initiating charge to ensure that the voltage reading is fairly accurate and the charger will "see" the true resting voltage of the battery and charge accordingly. If the battery appears to be discharged according to the chargers initial startup testing, it should go through the entire charging profile with maximum constant current initially which the battery will love especially if it is at least 40% of the 10 hour amp hour rating of the battery. The OMAX-6A-1B is a 6A ODYSSEY Ultimizer charger that is manufactured specifically for the powersports industry for up to the PC680 series sized batteries. It is a high enough amperage charger to perform deep discharge recovery (full amp output good for a discharged powersports sized battery) and maintain the battery at a full state of charge at the optimum recommended 13.6V [trickle] charging voltage.

If the battery is not fully charged when any charger goes into float, float voltage charging has to make up the difference to complete the charging process. The required float voltage range is 13.5-13.8V. We would highly recommend leaving any approved charger on the battery from use to use to ensure full charge especially for a motorcycle with an inadequate charging system. CTEK chargers with the snowflake setting (required for ODYSSEY) also work very well for seasonal powersports applications. They are plug and play as well.
 
This started in October, really?

AGM, Absorbed Glass Mat. It's a freeeking Lead Acid that doesn't leak when upside down. That's it, that's all.

If I saw a machine, any machine, charge above 14.5V, I would red flag it. 14.7V is damn near a condemn in my opinion. 15.0V pops bulbs at the very minimum.

Popping bulbs never happen in a nice warm shop when you are doing a PM but when the machine goes to work and the lights burn out every few hours, who do you think they call at 3:00 AM?

Throw those funky little electronic gizmos that act like fuses on a circuit board into the mixture, there is some Vegas gambling.

Now, at risk of trying the patience of the few that want to slam me, I don't mean to be a smartass but I seem to be perceived that way, if your battery bites, get a new one? Hang the warranty around the vendor's neck?

FLA, VRLA, AGM, GELL are the same!

Roger 04 RT, you are absolutely confidant in expressing your opinions here and you have the full and unconditional support of GSAddict and Happy Wanderer. At times it is very interesting from your perception how some stuff works. I am not taking away that your thoughts are pretty damn smart.

I have had my ticket as an HD Mechanic since 1979, add four years as an apprentice and you know what I take from that? I know I am not the smartest cat on the street and knowing I am right doesn't mean I am always right.

Do you want to tell the readers here that they need to install a Zenor Diode on the brushes of their alternator to own the battery you have?

I'm guessing that isn't your intention. I'm going to take a wild guess that you intended to find a solution to a problem you thought you had and it wanted to share it but it got away from you.

Here is a piece of advice: If you are the guy that puts the duds on at 3:00 AM to get your folks home/working, better to be simple than...................

Aye my boys, Have At Er, eh? Giver gud eh?
 
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