[Spunky99]

I noticed that after a month or 2 my engine turns over slower. I let it go until I got an engine fault light. It was the fuel pump relay. I cleared the code after recharging my battery.
Here is what I see. Battery charges, wait a week with it disconnected and it is at 3.13 v. Install it and same 3.13 volts.
Start bike and at idle is jumps from 3.20 to 3.30 with spikes to 3.4.
Rev it to 2500 RPM and the voltage stabilizes at 14.0 V.
So every time I start the bike, I am using battery power and at a stop, it really isn't charging the battery. I get a slight charge above 2500 RPM but since I drive 4.5 miles to work, that is not enough to replace the energy I used to start the bike.

Should I do the modification to increase efficiency or is there a problem with my charging circuit?

 

[DeanRider]

Batteries deteriorate over time, some faster than others.

I keep my bikes on a battery tender / Optimate charger when not in use. This maintains the battery, particularly against the rapid discharge cycle during our hot and very humid summer months.

Check this chart:

 

[DEcosse]

... Battery charges, wait a week with it disconnected and it is at 3.13 v. Install it and same 3.13 volts.
Start bike and at idle is jumps from 3.20 to 3.30 with spikes to 3.4.
Rev it to 2500 RPM and the voltage stabilizes at 14.0 V.....

Did you really mean 3.xx for all those readings ??? as in THREE.SOMETHING Volts???
Or was that just a typo?

Assuming it IS 13.xx, that is just float charge with no load - nothing to worry about if your alternator is providing >13V at idle

 

[Spunky99]

Sorry...all the voltages should have been 13 volts with the decimal values like this.
Battery is 1 year old.
I noticed that after about 4 or 5 months my engine turns over slower. I let it go this time until I got an engine fault light. It was the fuel pump relay. I cleared the code.
Here is what I see. Battery charged with a trickle charger, wait a week with it disconnected and it is still at 13.13 v as it was a week ago. Installed it is the same 13.13 volts.
Start the bike and at idle and it bounces from 13.20 to 13.30 with spikes to 13.4.
Rev it above 1500 RPM and the voltage stabilizes at 14.0 V.
So every time I start the bike, I am using battery power and at a stop, it really isn't charging the battery at idle. I get a charge above 1500 RPM but since I drive 4.5 miles to work, that is not enough to replace the energy I used to start the bike.

Is there a problem with my charging circuit?

 

[bradtx]

Spunky, My '98 at 1200 RPM has 13.7 VDC, at 2000 RPM+ it has 14.1 VDC. 12.97 VDC at rest. Mine does okay with slightly longer trips, less than 7 miles.

While your readings are slightly different (meter calibration?) than mine, I don't think you have a charging problem. You might however have a battery plate sulfation issue, which can cause longer than normal charging times plus reduced cranking amperage. How long the battery has been in service doesn't matter as it's more related to battery age and type of charger/tender. There are some on the market that help prevent, or at least slow plate sulfation.

Brad

 

[DEcosse]

Don't see any problems with your numbers Spunky


Sent from my iPhone using MO Free

 

[Spunky99]

Thanks bradtx and DEcosse,

The voltages looked good to me as well but I need other opinions to verify. I suppose my using the bike to commute 4.5 miles to work where I have to stop at several lights at idle is the culprit.
I guess I'll hit the battery with a trickle charge overnight about once a month to keep the battery up. It's either that or get on the freeway and drive for maybe 20 miles and then back once a week to get the battery full. Gas vs charger electricity (which is free to me in the garage).....

Maybe I will make a charger extension so I don't have to remove my seat. In the past I have always disconnected the battery and removed it from the bike to charge it. If I make up a female connector that I can get to secured to the frame and hook the trickle charger or a battery tender to the male end, I can let it charge when the electricity comes on with the security lights in the complex where I live. The electricity in my private garage comes on when the security light timer kicks on. So I do have 8+ hours of power each night for a battery tender to work. Is that the best method?

Is there a problem with a charge while the battery is connected?

 

[DeanRider]

Is there a problem with a charge while the battery is connected?

Not if you use an 'intelligent' charger such as the the Battery Tender or Optimate. Old-fashioned trickle chargers are not recommended -- even when the battery is disconnected from the bike -- particularly for sealed batteries as they can cause excessive heat and the 'bloating' of the battery case, leading to its possible catastrophic failure!

 

[DEcosse]

You don't need to disconnect battery to charge it - it's not disconnected while charging off the generating system while riding
Both Optimate and Battery Tender come with a fused 'pigtail' for permanent attachment to battery in the kit
you can put the connector end in various locations for access, I brought mine out on left side of bike just by the sprocket cover (can just as easily be right side)

 

[Felony]

The Battery Tender does not have a desulfation mode whereas the Optimate does. I've been using Tenders for yrs with lead acid batteries, but I may try an Optimate next time for this reason. However, if I ever do try a Li battery, the Tender can be used, but not the Optimate charger with the desulfation mode. Technology can certainly result in a closet full of limited use products.

 

[Spunky99]

Thanks Guys,

I ordered a Battery Tender Junior. That should do the trick.

 

[bradtx]

Thanks Guys,

I ordered a Battery Tender Junior. That should do the trick.

It won't hurt to leave the battery tender connected when parked for any period of time. A charged battery is the best defense in preventing a sprag clutch failure.

Brad

 

[Spunky99]

It won't hurt to leave the battery tender connected when parked for any period of time. A charged battery is the best defense in preventing a sprag clutch failure.

Brad

That's what I hear....an engine teardown for a sprag is a sad thing!