Topic: Another Battery question: Effecting Gas mileage?

[KB02]

Okay, here's the short and skinny:
2000 Ducati Monster 750 (Dark).

My 6 1/2 year old battery is finally starting to show it's age and a replacement has been ordered. For six years this thing has been like new, but in the last month it has taken a dramatic fall from grace, thus leading to my question:

I have noticed a systematic decline in my gas mileage over the last couple of years. From an average of 50+ miles per gallon dropping down to low 40's. In the last month the bike has been running VERY poorly (sputtering, fouling plugs, not warming up like it used to, and very low idle). It has also had extremely poor gas milage, down to 38 miles per gallon on the last tank.

Could the weakening of the battery of had any effect on the gas mileage? Perhaps a weaker spark not firing as good as it could have been thus leading to reduced gas mileage and soitier plugs?

Or am I just pulling at straws here?

The Carbs were cleaned and balanced at a service this spring. The only other thing that I can think of is a bad choke linkage and the battery thing is just a coincidence. (I haven't had time to dive into it myself and I can't afford the shop's labor rates right now)

Any thoughts?

[Pinhead]

If your alternator is working I don't think the battery would really have that much effect on the system, at least with the engine above 1500 rpm. Below 1500 and everything is being pulled from your battery. Above that, and it's all your alternator system. HOWEVER, if your charging system is even borderline weak, it may not be able to keep up with running all of the lights in conjunction to trying to charge a bad battery, and low voltage is the result. With the engine running, make sure your alternator is charging to the correct voltage above 2k rpm.

Or... You'll have to replace the battery anyway, so just change it and run a tankfull through.

[BobbyR]

Well if your battery is calling for a lot of charge the alternator is working harder, the harder it works, the harder the engine works to turn it. That means you need a greater throttle opening to maintain speed and accelerate.

[cb(r)]

dont do anything until you get the new battery.  if things stay the same you know it is not the battery.   then check the easy stuff.  check plug gaps and make sure you are getting strong spark.  I used to have a similalr prob with my old fzr 600  .  I would just run 1/2 race fuel with 1/2  92 plus octane once in the spring and once in the fall.  it seemed to help.?  it worked until I finally had to rebuild the carbs.  they had bad o rings.

good luck

[KB02]

Wel, I checked with a Ducati sight they pretty much said the same thing. The battery is not the cause of my problems. However, changing the plugs seemed to help the mileage and the starting. Maybe I can run this battery for the rest of the season and say that  got 7 years out of it. (I didn't even get two years out of that battery that I bought for my Honda at Walmart).

[johnny-from-bel]

As for the question. a K6 750 engine will produce 48000 watts at the cranck. The alternator will  produce at best 150W given a yield of 50% it wil take 300Watts from the cranck that is 0.7%. I do not think it will matter much.


In 2003 I wrote following mail to the sohc4 mailing list.
Until today (2006) the mentioned test battery is still in service.



There have been a lot of messages and discussions on using EDTA. I decided
to try it out for myself.
The object of the test is a battery that I put out of commission 3 years
ago because it could not hold its charge (red light on my batt. charger).

When I diched out the battery it was 90% dry. So I topped with distilled
water, the tension was 5.5V.

So I ordered some EDTA and followed the instructions ; disolve in water and
add 0.5ml per cell for a 12AH battery.

Shake and leave it for a few days. Visualy I can see chips of coppersulfate
falling to the bottem. This means the sulfate is comming lose from the
plates. As it does not conduct electricity it does not do any harm. Now for
the test, I hooked it up to the charger. Orange light good sign, after two
days on the charger still no green light. So I decided to add an other 1 ml
EDTA solution and repeat the treatement. Still no green light after 3 days.

So far I had only been charging so I deceded to reverse the process and
hooked up a 12W lamp for a night. In the morning the battery was completely
depleted (0V). I unhooked the lamp and put the battery on the charger after
two days I had a green light from the charger.

If not completely, the EDTA tratement has made the battery usable again.

I am now adding 1 ml EDTA solution to every battery I have. Just to slow
down the sulfatation process.

This is just my personal experience, yours may vary.

Johnny-from-belgium.

[KB02]

Interesting.

Hmmmm........

It's weird, too. Friday morning when I went to pick up the bike at the shop (for my $200 new chain) they couldn't get it to start because the battery was so low. They jumped it to get it going and the rest of the day went fine (as was it's pattern). Saturday morning, as I sat at a motel a couple hundred miles from home with a bunch of motorcycling friends I figured I would try the starter to see how many of my friends I would need to push start te bike. It started right up like there never been an issue. All that was changed was the chain and the plugs.

[dusterdude]

must of been the chain.

[KB02]

Well, that is my new theory, anyway. Full tune up in the spring in which I was billed for new plugs, but did I get them? The chain has been in need of replacing for a while, I just couldn't afford it. SO: Old plugs that were not firing great; and old chain that was holding the bike back both declining the bike of running like it should have been thus reducing mileage. New plugs and chain and the tune up was able to do the work it was supposed to and my mileage has been regained!!!

  still doesn't explain the battery, though... oh well. the new one is sitting on the living room floor just waiting for electrolite... next spring perhaps.

[csendker]

So I ordered some EDTA and followed the instructions ; disolve in water and
add 0.5ml per cell for a 12AH battery.

What's EDTA?

[Bob Wessner]

I wasn't familiar with it either, found this;

What on earth is EDTA?
Pb is the symbol for lead on the periodic table. Your battery gets a certain amount of lead in its plates when it is new. Some of that dissolves into solution when you pour in the acid. Some of it turns into lead sulphate when things are not working quite right. (Adding EDTA prevents that.) If you allow the extra liquid to boil off the lead stays in the battery. The liquid does not actually boil in that it never gets that hot. It DOES electrolyze into hydrogen and oxygen and the vapours go away. Anyway, if the lead stays in the battery, you haven't lost anything when the level draws down except for water, which you happily add back in (in the form of DISTILLED water). Removing electrolyte is not a good idea. There is Pb (lead) dissolved in the electrolyte and you'll diminish the capacity of your battery by removing it. The battery on the F boils off electrolyte fast enough that it won't be overfilled for long.

The EDTA somehow keeps lead sulfate from forming (or keeps it soluble). The lead sulfate is formed from the lead + the sulfuric acid in the battery. Lead sulfate is insoluble in the electrolyte, and sinks to the bottom of the cell when it flakes off. When the pile of lead sulfate gets big enough, it bridges the gap between the plates, and you get a dead cell. If it doesn't flake off, it reduces the effective surface area of the cell, slowly reducing its capacity.

EDTA works by binding divalent cations (lead in this case) therefore inhibiting the formation of lead compounds. For already formed lead sulphate...the reverse reaction is probably enhanced (not sure). Tetrasodium-EDTA is relatively water soluble compared to disodium EDTA. If you dissolve it in water first you can then add it to battery electrolyte which is approx 4M sulfuric acid. I don't know how long it stays in solution. If you dump the powder straight into the battery very little will go into solution. If the 'powder dumping' approach yields results it suggests that very little is actually needed. As per Google, In general, use one tablespoon per cell in a golf cart battery such as a Trojan T-105. There are approx. 40 tablespoons in one pound. George#384

See http://www.deathstar.org/~flash/edta.html for a heap more information on EDTA.

[johnny-from-bel]

So I ordered some EDTA and followed the instructions ; disolve in water and
add 0.5ml per cell for a 12AH battery.

What's EDTA?

EDTA is ethylenediaminetetraacetic acid. As said it will prevent lead sulfate from forming. In contradiction to the above crystalline lead sulfate (PbSO4) does not conduct electricity. It does reduce contact area and so reduces capacity. I have a battery where there is about 1 cm of the stuff lying at the bottom. The battery is still in use on the K6. Won't turn the starter more than a few times but will kickstart OK.