- Q - about RPMS and battery charging ???

[getsum]

OK - went out to drive the 78 GS1000 to work this morning.

Well it would not crank over.
It usually does this with no problem - just a little choke....

I could tell the battery did not give it enough juice to kick it over.
-- The battery is not new.
-- It has been sitting a week.
-- It is not normally hard to start.
-- WEATHER -- The last 5 mornings/days or so it has been considerably cooler 60s -to 70 in the morning mid 80s during the day verses the normal 80 higher in the morning and 99-105 in the day.

I normally drive it to work 3- 4 times a week with no problems.
HOWEVER It is normally stop and go with no higher MPH than say 45-50 and usually around 3000-3500 RPMS MAX.
(When it is up to 4000 rmps or so it is not for long at all if hardly ever ) -stop and go traffic

SO-
IS THE BATTERY even getting a charge with the RMPS staying so low ?
Should I drive it on the HWY once or twice a week to get the RPMS up enough to get the battery to charge.

I plan to check the battery tonight and hook it up to a 6 volt trickle charger for a bit --- Is that the right thing to do ??????????

[emjay]

Right or not, I put mine on the trickle charger when it sits for more than a couple of days.

[babcockdonald]

Okay, here is what I have been told on this subject. As long as the stator and the r/r are working properly the battery charges properly at above 4000 rpms. If you run the bike at mostly 3000-3500 rpms then it probably isn't getting a full charge from riding. Try running in a lower gear to maintain the 4000+ rpms.

Trickle chargers are highly recomended if the bike is going to be sitting for more then 1-2 days, especially on these old bikes. I have a 79 GS1000 that runs everyday of the week (except right now because of needing to be fixed). So I haven't had to invest in a trickle charger. I know of several people that have permanent hookups to thier battery so when they get home they put the bike in the garage and plug in the charger. They have been doing this for years on bikes that they run only 2-3 times a week.

The smaller trickle chargers are all you need, as long as it is a decent brand. I will look around to see what the brands are that you should look into.

[rustybronco]

I plan to check the battery tonight and hook it up to a 6 volt trickle charger for a bit --- Is that the right thing to do ??????????

Do not use a 6 volt charger the bike has a 12 volt system

[getsum]

Do not use a 6 volt charger the bike has a 12 volt system

So I should get a 12 VOLT Trickle CHARGER ????
A 6 VOLT will not do the trick on the little motorcycle battery ???????


I did not know they had one of those in 12 volt as a trickle charger ----

What do you guys recommend.??????

[getsum]

Well guys --

Went by "The Sharper Image" on the way home.
They had a cool battery tender that I had been interested in getting anyhow.

Hooked the battery tender up to the battery once I took it out and it red (LOW) so I have it set on the 2 amp mode for a 12 volt battery.
It is charging the battery as we speak. Coll thing is once the battery is charged it will shut off and monitor the battery. Thus if it needs more at any time it will charge it by just turning on.

Cool thing is it also came with an adapter that you can putonthe battery for the bike and just plug it in once I get the bike in the garage and feel I need to charge it up.

I believe the reason it was not charging is that the low RPMS that I run the bike at are not high enough to charge the battery on a consistant basis.
-----What do you think ????

ANYHOW -- HERE IS THE BATTERY TENDER: I recommend it for only $30.00

http://www.sharperimage.com/us/en/catalog/product/sku__SI263BLK

-JOE

[crc1214]

How long have you driven it 3-4 times a week to work, going below 4000 RPM's, and been just fine when you go to start it? If you've done this for a year, and been just fine until just recently, I'd say it's just time for a new battery. Take it to AutoZone or Advance Auto Parts and have it load tested (free of charge). If you need a new one and are on a real tight budget, get their brand (25-30 bucks out the door in these parts, decent batteries)

If you can spend a bit more, get a maintenance free sealed battery from these guys. I recommend these guys so much they should set me up on their payroll....

http://www.batterymart.com/battery.mv?c=motorcycle

About 53 bucks and it will be on your doorstep within a few days, fully charged, ready to go.

[Boondocks]

Well guys --

Went by "The Sharper Image" on the way home.
They had a cool battery tender that I had been interested in getting anyhow.

Hooked the battery tender up to the battery once I took it out and it red (LOW) so I have it set on the 2 amp mode for a 12 volt battery.
It is charging the battery as we speak. Coll thing is once the battery is charged it will shut off and monitor the battery. Thus if it needs more at any time it will charge it by just turning on.

Cool thing is it also came with an adapter that you can putonthe battery for the bike and just plug it in once I get the bike in the garage and feel I need to charge it up.

I believe the reason it was not charging is that the low RPMS that I run the bike at are not high enough to charge the battery on a consistant basis.
-----What do you think ????

ANYHOW -- HERE IS THE BATTERY TENDER: I recommend it for only $30.00

http://www.sharperimage.com/us/en/catalog/product/sku__SI263BLK

-JOE

If the battery isn't relatively new, it probably needs replacing. If a battery isn't kept fully charged it will gradually sulfate and can't be restored to full capacity. The charger you bought is not a Battery Tender. Battery Tender is a registered brand name of a specific high quality "smart" (microprocessor controlled) battery charger. I don't know who makes the one that you bought, but if it has a cooling fan (like a computer fan) you could have problems. I bought a Schumacher charger similar to the one that you bought and had to bring both back to the store when the fan started squealing in cold weather. I tried another one and it did the same thing. I gave up after that and bought high quality smart chargers without cooling fans.

[arveejay]

The following is taken from the stator papers on this site. The stator will not charge till a minimum of 4000 rpm's are acheived.



On idle, not too much will happen, since the stator simply isn't revolving fast enough to generate enough current. Depending on the bike, you may see it rise a little, to something like 13,5 V or so.
Now we rev it up to a reasonable speed, say, something like 4000 RPM. Now you should see full charge, somewhere in the range of 13,9 and 14,5 Volt.

[getsum]

4000 - That is what I thought.
I rarely stay over 4000 for a constant period of time.
Hell I hardly ever even get to 4000 rmps.
60 mph is at 3500 on my bike.

[Boondocks]

The following is taken from the stator papers on this site. The stator will not charge till a minimum of 4000 rpm's are acheived.



On idle, not too much will happen, since the stator simply isn't revolving fast enough to generate enough current. Depending on the bike, you may see it rise a little, to something like 13,5 V or so.
Now we rev it up to a reasonable speed, say, something like 4000 RPM. Now you should see full charge, somewhere in the range of 13,9 and 14,5 Volt.

It's a worthy effort, but Part 1 and the FAQ in the stator papers were written by a non-technical person and has some questionable interpretations and conclusions. The article in the stator papers doesn't say that it is necessary to run the engine at 4,000 RPM to charge the battery. It is not. Any time the voltage reading rises above full charged battery voltage (12.7V-12.8V), the stator is charging the battery. The lower the charging voltage (and current), the longer it will take to charge the battery. 13.5V will charge a battery if enough time is allowed, but it will not allow the battery to gas and prevent excessive sulfation. Eventually, the battery will diminish in capacity and die.

[arveejay]

I looked at my Suzuki 1100 OEM service manual as I'm sure they all should test the same. This is what the little guys that made the bike have to say on the matter, you know, the Japanese. This is page 11-7 in my Factory Genuine Suzuki GS1100 Service Manual, MAY 81 . They're saying 5000 RPM.

[Boondocks]

I looked at my Suzuki 1100 OEM service manual as I'm sure they all should test the same. This is what the little guys that made the bike have to say on the matter, you know, the Japanese. This is page 11-7 in my Factory Genuine Suzuki GS1100 Service Manual, MAY 81 . They're saying 5000 RPM.

Bob, 5,000 RPM is a standard test setting to verify that the output of the charging components is within spec. If the charging outputs don't fall within the specifications for the stator or R/R at 5,000 RPM then they are faulty. This has nothing to do whatever with a RPM value required to charge the battery. There is no such RPM value stated in any manual. BTW, the 5,000 test standard is in Part IV of the Stator Papers - Fault Finding which was basically copied from writings of Ritzo Muntinga of Electrosport.