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Starter or Battery 2004 R1150RT

All I can say to the prior post is, wow! You need to do some homework. Odyssey and others are very clear about the charging requirements of agm batteries. Others who own the pc680 have done discharge measuments and discovered the same state of charge as mine, about 2/3.

I highly doubt that many will mod their VRs by adding a silicon rectifier diode (which is not a Zener diode). That is why I asked odyssey for its guidance on how a user can maintain a 100% State of Charge which is two posts back.

Shortly I will post some follow up comments from odyssey on other considerations for maintaining 100%.
RB

P.S. My average cold-soak starting time, at temperatures as low as 19F, is under 1.5 seconds.
 
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Here is some further clarification from Odyssey.

Roger -

A few additional thoughts.

1. Most PowerSport vehicles have charging systems with relative low operating (charging) voltages because of the fear of boiling out a wet flooded battery and dealing with the acid corrosion issues. Their philosophy is better to under charge the battery and minimize the gassing than charge correctly and out gas the battery. In going to ODYSSEY and not having the corrosion issues, correct charging - operating voltage is critical to getting the long life ODYSSEY has to offer.

2. We don't expect PowerSport vehicle owners to do what you did in correcting the charging system voltage, so a solid alternative is to use a 6+ amp charger - maintainer on a continuous basis when the bike or vehicle is the garage. Continuous float charge will correct under charge from the bikes system.

3. The ODYSSEY Ultimizer OMAX-6A-1B is a great little charger - maintainer if you can live with the continuous cooling fan noise. If not, use the CTEK US Multi-7002 and use the Snowflake battery selection algorithm.

Bruce R. Essig
National Sales Manager
Program Distribution Groups​
 
Perhaps a little less "YODELing"

Post edited.
I've delayed any further Odyssey tests till this weekend when I have more time.
In support, I appreciate a post such as this one, and seek the depth and detail (if I didn't I would simply go do something else).
Lorne.
 
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All I can say to the prior post is, wow! You need to do some homework. Odyssey and others are very clear about the charging requirements of agm batteries. Others who own the pc680 have done discharge measuments and discovered the same state of charge as mine, about 2/3.

I highly doubt that many will mod their VRs by adding a silicon rectifier diode (which is not a Zener diode). That is why I asked odyssey for its guidance on how a user can maintain a 100% State of Charge which is two posts back.

Shortley I will post some follow up comments from odyssey on other considerations for maintaining 100%.
RB

P.S. My average cold-soak starting time, at temperatures as low as 19F, is under 1.5 seconds.

At the risk of being accused of being in collusion with Roger, I am compelled to agree with the above.
+1000
Calling the Happy Wanderer to the courtesy phone...........
 
Evening Roger,

Hmmm.. kind of have to agree with DieselYoda in that gel or AGM batteries are really just different versions of a lead acid battery and do, of course, exhibit somewhat different properties than the old standby flooded lead acid but still are basically lead acid bats.
 
Evening Roger,

Hmmm.. kind of have to agree with DieselYoda in that gel or AGM batteries are really just different versions of a lead acid battery and do, of course, exhibit somewhat different properties than the old standby flooded lead acid but still are basically lead acid bats.

Odyssey disagrees with your statement and is clear on the charging requirements for its batteries. The Oilheads with the stock voltage regulator don't meet those specs. A key may be to keep the battery fully charged and then to either regularly top up as they recommend on take long enough rides that the trickle charge voltage level of the stock bike tops it up.

I'm pleased with the vreg mod but seriously considered just topping up with a charger.

For me, the most interesting aspect of this project was the discovery that an undercharged pc680 delays starting of the 2004 R1150 with dual spark (probably other 1150s with the same injectors). When I first began the debugging many wrote to tell me that all Oilheads take a long time to start, that turned out to be wrong.

Tomorrow I'm going to discharge the battery a few percent and time the recharge interval at 13.7 and 14.5 volts to see how long you need to ride at the stock voltage to fully recharge.

An issue raised earlier about higher operating voltages deserves comment. Increasing the voltage regulator by 0.7 volts does two things: subjects electronics like the Motronic, ABS and RID to a 5% higher operating voltage and increases power dissipation in lamps. One of the businesses I was involved with tested automotive electronics in the US, Europe and Japan, those products were always tested at higher voltages than my reset alternator. The 5% higher voltage delivers 10% more power to the incandescent lamps. I can already see that indicator bulbs glow a bit brighter. That should shorten their operating lifetime, maybe by the 10% that I've increased the power dissipation. I can live with that.
RB
 
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Evening Roger,

Hmmm.. kind of have to agree with DieselYoda in that gel or AGM batteries are really just different versions of a lead acid battery and do, of course, exhibit somewhat different properties than the old standby flooded lead acid but still are basically lead acid bats.

But that is where it ends from a charging/maintenance perspective.
 
But that is where it ends from a charging/maintenance perspective.

I would certainly agree with that. Started the '04RT this afternoon and looks like I am in need of a new battery myself and I am going with a Yuasa flooded cell battery mainly because this battery is easy to charge with a conventional charger and likes the BMW charging system in stock form. Also, it's CHEAP! Kind of like me.:blush

Hi Roger,
Your Odyssey AGM battery has lead plates separated by the electrolyte (sulfuric acid) infused glass mat material. Hence, it is a lead acid battery. To be sure an AGM battery has some very superior characteristics to those of a flooded cell design no argument there.
 
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I would certainly agree with that. Started the '04RT this afternoon and looks like I am in need of a new battery myself and I am going with a Yuasa flooded cell battery mainly because this battery is easy to charge with a conventional charger and likes the BMW charging system in stock form. Also, it's CHEAP! Kind of like me.:blush

Hi Roger,
Your Odyssey AGM battery has lead plates separated by the electrolyte (sulfuric acid) infused glass mat material. Hence, it is a lead acid battery. To be sure an AGM battery has some very superior characteristics to those of a flooded cell design no argument there.

Hey Jim, I think we're saying the same thing. The construction and chemistry of conventional flood lead-acid, Gel and AGM isn't really what's in question. What's been of interest is that they require different charging voltages and currents. And what's actually been important is that an undercharged PC680 has a material effect on how the R1150 starts after sitting for a day--a real surprise to me but there it is.
RB
 
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Increasing the voltage to a bulb by 10% will shorten its life by something greater than 10%; sorry I don't have the actual numbers, but I recall reading a blurb (from Sylvania?) about this a while back.

QUESTION: OK, we know that the wiring in some places is not as robust as it could be... Are there any specific places where it would be beneficial to either replace the wire with a larger gauge, or add another in parallel, to reduce the voltage drop along that run? One place might be the cable to the starter, another could be the main ground from the battery; where else...? Throughout my career, it was always clear that one should Never depend on a chassis or frame for a ground return; maybe adding extra grounds point-to-point?
 
Throughout my career, it was always clear that one should Never depend on a chassis or frame for a ground return; maybe adding extra grounds point-to-point?

Are you saying that a ground strap should be connected to the battery for each ground needed? I can think of good examples where that would have saved a lot of grief trying to figure out why a controller acted goofy and it was grounding problems.

I have always maintained that the grounds connected to the frame have to be adequate and clean. I would never have thought the frame itself is inadequate.

Grounds, grounds, grounds must be clean. That was drilled into my head as an apprentice.
 
Increasing the voltage to a bulb by 10% will shorten its life by something greater than 10%; sorry I don't have the actual numbers, but I recall reading a blurb (from Sylvania?) about this a while back.

QUESTION: OK, we know that the wiring in some places is not as robust as it could be... Are there any specific places where it would be beneficial to either replace the wire with a larger gauge, or add another in parallel, to reduce the voltage drop along that run? One place might be the cable to the starter, another could be the main ground from the battery; where else...? Throughout my career, it was always clear that one should Never depend on a chassis or frame for a ground return; maybe adding extra grounds point-to-point?

Thank you for the suggestions.

I think you're correct about the bulb lifetime being reduced. Here's my thought, the voltage has been increased by 5%. The power being dissipated by the bulb is up by 10%, that's why I suggested the 10% estimate for lifetime reduction, still it would not surprise me if it was more than 10%. That said, other bikes using similar bulbs have 14.5 volt system voltage.

There are three approaches I could take now: connect a power diode in series with the main +12V feed to the lamps; add a relay with a half hour timer across the boost diode to drop the system voltage after a charging interval; or don't worry about it. I'm going with the third option.

I have measure the resistance of my main grounds. They are quite good. It seems like they are in the vicinity of a couple milli-ohms. At this point I've satisfied myself through measurement that the key problem was increased battery resistance due to chronic undercharge (67%), due to low alternator voltage, frequent short trips, my frequent in-garage testing and my use of the BT Jr. Having corrected the battery problem my bike now starts in 1-1.5 seconds even in cold weather after sitting a day.

Are you saying that a ground strap should be connected to the battery for each ground needed? I can think of good examples where that would have saved a lot of grief trying to figure out why a controller acted goofy and it was grounding problems.

I have always maintained that the grounds connected to the frame have to be adequate and clean. I would never have thought the frame itself is inadequate.

Grounds, grounds, grounds must be clean. That was drilled into my head as an apprentice.

Agreed, grounds are critically important. In my case I've measure the key grounds and satisfied myself on that one. Also, I've studied the grounding method used on the BMW R1150s and it is quite good. They do a good job of isolating the key pieces. (Although the headlight lamp has a ground that seems to fail easily.) As I mentioned above, the cause of my slower starting is set. Now I'm just trying to communicate the supplier specs for charging the Odyssey batteries and make some tests to confirm them. It's pretty clear that to get back to full charge with a 13.7 voltage alternator is takes a LONG time.

RB
 
Added connections add potential failure points.
The best/shortest ground path is the way current is going to flow. I have paralleled certain conductors, but try to have the same length when I do. Stranded welding style cable is great for battery leads.
The Airheads have many ground leads terminating under the tank to the frame at the coil bracket...it's a common area for a bad ground connection.

And Way off topic...kind of

In AC circuits, you can cause stray voltage issues with too many grounds...think wet concrete floors and metal water troughs and four legged animals. Many times I have gotten tingled reaching into the water as well...cows will not drink from it. It can be as simple as a bad ground at the service panel, the common neutral bonded to the steel structure and/or the cold water pipe, and a driven ground rod at the utilities transformer and a better one at the service entrance or another out-building. The unbalanced load current is looking for the best ground...sometimes it's thru the cows! Very hard to isolate!:banghead

OK, back to the original topic:whistle
 
We had a saying: "Ground ain't ground the world around." But we were dealing with the whole electromagnetic spectrum, everything from DC to light, and different frequencies and different modulation (data transmission) formats have different requirements. Ground loops (showing up as a higher noise floor, discontinuities, or unwanted signals at specific frequencies) caused many headaches and schedule slips (troubleshooting & repair) due to failing to meet test requirements.

"Ideally" every wire (including grounds) would be as large and as direct as possible... but the world is not an ideal place, nor are production lines looking for ideal solutions.
The best conductor is silver, but this is expensive, not mechanically strong, and tarnishes quite easily (thus the gold plating on many electronic items). Copper alloy is the common solution (and let's NOT get into the oxygen-free debate again; physicists already know the answer to that).

Frames are typically a steel or aluminum alloy; this suggests a lot of room for improvement. That's why I was thinking that adding extra cables might be somewhat worthwhile; but if the factory setup is "quite good", then maybe not... maybe just in a few very specific places, like the primary power cabling, or jumping (adding) across frame junctions.
Keep in mind that as current (draw) increases, the voltage drop through that particular path also increases.

One correction for Steve - Current will flow through any and all offered paths, not just the shortest one.
 
One correction for Steve - Current will flow through any and all offered paths, not just the shortest one.

Your right...that's the problem some times... in "theory" it's supposed to take the shortest path, but like my cow story....does not:thumb

Try grounding power systems in limestone...:banghead
 
Theory clearly states "All" paths... Ohm's law, Kirchoff's Law, nodal simulation & analysis, et al.
Your lights can function when the ignition is on, your horn can function, your brake light can function...
These are all essentially in parallel by virtue of being connected to the 12 volt buss. And it doesn't matter if we're talking about microvolts or lightning bolts.

And yes I've been zapped by the wire around a pasture! It was while I wasn't paying attention; my "buddy" said "Here, hold this a sec..." Paybacks...

But now we truly digress from Roger's topic! I was just seeking ways to possibly improve the all-around voltage delivery.
 
Got ambitious and did a cold start cranking test while monitoring battery voltage on my '04RT and observed a low of 8.5 vdc with very slow cranking. Couldn't find a Yuasa flooded cell battery for an 04RT so I ordered a Panasonic LC-X1220P VRLA 12V 20AH battery for $85 from Digi-Key. Same battery from Amazon was $104 so not bad. I can't really complain as the Westco sealed LA lasted 6 years. Decided on Panasonic after reading the reviews on Amazon and it doesn't appear that this battery has any special charging requirements as does the Odyssey, I hope.
 
Nobody has mentioned battery temperature.

Battery temperature has a direct affect on capacitance, not necessarily voltage. I can say that in my experience, especially in the Arctic, a perfectly good battery at room temperature will act like a boat anchor when at freezing temperatures.

I can from great experience say that GEL, AGM and VRLA are horrible when temps get real cold. That's my experience. I like the old style and I change them every three years, if not sooner. It is just the way it with winters here.

I have seen data that I rather doubt at times that most batteries below freezing can loose up to 80% capacitance. I don't know if that's accurate but I can tell you, today, a battery blanket would be a good friend. As well, if your car doesn't start on a cold day, put your headlights on for a few minutes. I know it's counter-intuitive (WOW, big word for me!) but it works sometimes. Sometimes working is better than not at all.

I can also tell you that today, my bike outside with a cold soak, won't start even if I boost it from a bulldozer. I doubt I want to put 0W30 just so the engine turns over. With the oil in the diff/rear end and the tires, my adventure would not end well at this temp.

Square tires are not an urban legend.

I'm sorry if I went off topic.
 
...

Frames are typically a steel or aluminum alloy; this suggests a lot of room for improvement. That's why I was thinking that adding extra cables might be somewhat worthwhile; but if the factory setup is "quite good", then maybe not... maybe just in a few very specific places, like the primary power cabling, or jumping (adding) across frame junctions.
Keep in mind that as current (draw) increases, the voltage drop through that particular path also increases.

For the most part, the wiring is okay. The headlight seems to be a weak spot, with a few reports of problems every year.

Relative to starting, I found several things that I reported earlier in the thread: three spark coils are powered by the key switch they could be run to the battery through a relay; the fuel injector volume versus battery voltage isn't well compensated by the Motronic leading to lean slow starting; and dwell time versus voltage seems overcompensated.

Of all those issues I would probably rewire the coils first. They did on later 1150 twin spark machines. The other annoying thing on the wiring is that the lights come on before the motorcycle starts, draining a weak battery.
 
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