Guys,

I had an issue starting my DR-Z, and bought an optimate to charge the battery.

The battery was showing 12.2V before I charged it.

The battery test LED was steady at the same time as the 0.2A LED, which in the manual for my charger states the following:

"this is a definite indication that either the battery has a short circuited cell, send it for recycling or replace it".

Although the above indication suggested my battery is buggered, it's now putting out 13.15 volts with the engine and ignition off (with a trailtech on the permanent live)

The bike now starts perfectly, and idles much better than it ever has, used to have to keep it on choke for ages or it would die.

It also turns over alot faster than it used to!!!

With the engine running at what I'd probably say is fast idle (I have no RPM meter, and the idle seems to be set fairly high) the battery is showing 14.03 Volts.

When the bike is revved, this figure drops down to around 13.8v throughout the rev range (no RPM meter!)

I have read the troubleshooting FAQ, and it says the voltage isn't actually dropping, but as long as it reads above 14 then its OK?? Does this mean it's OK to have 14v at high idle, or when it drops on my meter it must always be above 14v?

Would the apparently dead cell in my battery cause lower readings?

I started to look at the connections from the reg/rec and tried to trace them, but didn't find it easy and ran out of time. I saw this red wire and connector near the battery, does this come from the reg/rec? If so this connector casing looks greenish, is this normal or is it oxidised?



The connector itself looks full of mud, I've cleaned it up a little by scraping it with my multimeter needle, but need some proper cleaner for it really, could this be having an impact?

My real issue is I'm not sure if I've just got a dodgy battery as the optimate suggests, or I've got a charging problem as my battery readings suggest (but its 14v at high idle).

Would doing the free power mod solve all my problems by obtaining an extra 0.5v?

Cheers,

Con

The 14 volts that you have at fast idle and above suggests that your stator and regulator rectifier are working fine.
As far as your battery goes, if you'd dropped a cell it would be down around 1.5 volts, as it starts the bike fine, I'd say it probably charges ok, but, may struggle to hold that charge for any time.

Thanks Harvey, so the optimate is not to be trusted? I'll keep an eye on the voltage the battery is showing over the next week and see what happens.

Is it not important to measure the amps coming out of the battery as well as the voltage, or is this a given?

Also is a low battery capable of making a bike difficult to idle?

Cheers,

Con

Brick-top said:

It certainly could be useful. The battery could show decent voltage, but not hold much in terms of amperage. I had a car battery do this to me once. You could also probably take the battery to a shop and have them run a test on it to be sure.

Charge the battery, test the voltage right after you remove the charge leads, test again 15 minutes later, and finally test again a few hours later. You should see over 13v immediately after removing the leads, about 12.6v 15 minutes later and the same hours later. If it keeps dropping over time you have a bad battery. Oh, be sure to remove the battery from the bike or at least disconnect all the cables from it when testing.

Brick-top said:

You can't measure amperage coming out of the battery as such, you can only test the amperage flowing through a given circuit, you have to put the amp meter into the circuit, then switch the item on, the meter will show you amps (providing you have a meter with either an amp scale and one capable of measuring the current of the circuit on test)
The optimate is a fine tender/charger I have 3 and have no problems with any of them.

ptgarcia said:

Try as PT suggests, it's as good a test as any, plus you don't have to buy anything else to do it!

Harvey600 said:

What do you make of the statement in the optimate manual about the constant green test LED, and the constant 0.2ah LED being lit at the same time, and this indicating a short circuited cell???

ptgarcia said:

I had

well over 13v immediately adfter removing the leads, and still maybe 30 mins later I had the same...

I'll test again on the weekend and see what the battery reads. If its going down, does that indicate the battery is broken or the charging circuit?

Harvey600 said:

What if the cell is slightly faulty, i mean the battery was registering 12.2 before i used the optimate on it, so this is just over a volt down.

Perhaps the optimate can charge the cell but the cell can't keep the charge, I dunno!! I just think the optimate should be right!

I'm thinking the state of charge in your battery was so low the Optimate initially thought it had a dead cell. Have you been getting that same code even with a fully charged battery?


If a cell can't hold a charge you should be able to tell after only a short time after charging. Once removed from the charger battery voltage would immediately start dropping.

I charged the battery out of the bike, and it started charging at 0.8a, if it was severely discharged it would have gone itno recovery mode and charged at 0.2a, then 0.8a

do the free power mod.the connector coming out of the reg/recif is a troubleson spot for corrosion and thus bad voltage readings(but it sounds like your ok there)

Overall your battery sounds fine.

I don't know enough about your charger to comment.

I think the charging system output is fine.

You need to do "Free Power" but you also need to replace that "green" connection. That is the troublesome one that goes to the fuse and runs the whole bike. It is important that, that connection is good even after Free Power is done. Free Power gets power to the battery. That connection gets power to every place else.

About the only things that you need to do to your battery are to ensure that resting voltage is over about 12.4 volts and check that the fluid is at the proper level. The earlier suggestion to check voltage is correct, yet a bit flawed. Essentially, batteries retain a bit of voltage after charging that won't tell you anything about their state. You have to let the battery set for at least a couple of hours to obtain a proper reading.

A good rule of thumb is to replace the battery if its resting voltage drops below 12.4; however, I have waited until around 12.15v to replace. Just be aware that batteries can experience a quick failure when they approach that 12v mark. A bad battery can most certainly cause a rough idle condition.

Your plan to ride the bike and monitor its voltage is a good one. ;)

Well I would've ridden the bike today, but the f*cking thing wouldn't start!!!

Seems to crank over just fine, but not firing!

So next steps, clean up the green connector on Page 1, and check voltage at the battery again.

lynk- your voltage numbes are low for AGM batteries. And it is sealed so no fluid level check. There is actually very little to none free fluid in it anyway. It is all absorbed in the fiber mats.

Yes, it should sit for an hr or more and retain 12.8 to 13.2 v.

A DRZ400 E, S, or SM produces enough electrical power at idle to run the bike with no added battery power. So it should have no affect on idle. If a battery is out of the circuit or shorted internally or some other severe problem, then it might have some affect.

Brick - If it cranks fine, I doubt it is a battery problem. Check for voltage at the CDI. The ignition will make sparks until the digital display dies some place around 6 volts.

Brick-top said:

If it is cranking and not firing...try a fresh plug. Yours may be fouled somewhat from your old habit of riding with the choke on for a period of time.

I got it started tonight, was alot warmer than the very cool morning we had??

I had to crank it over for what i'd call quite a while, but it fired up.

Before doing this, I checked the voltage at the battery, which was good.

I also cleaned up the dodgy connector with WD40.

Will continue to keep an eye on it, but am suspecting the plug more and more... Got one ready to go so :)

WD40 won't solve your corroded connection. Need to cut it out and replace. I'd just cut the corroded section off and solder the wires together. Insulate it well after. I usually use shrink wrap...but electrical tape would do.

Noble said:

Here's my common reference for batteries: Deep Cycle Battery FAQ

I just replaced a Lead-Antimony plate battery in another bike, and got the two confused. So, you're absolutely right about the type of battery specified for our bikes; however, the same voltage measurement rules apply. See the above article for more information.

BTW, when buying a new battery for your bike, always see if you can find one that is sold with an acid pack - it's the only way to know your battery is fresh.