XR600R Battery Problem

[DSTerry]

I converted my 89 XR600 electrical system to an AC/DC system using a ricky stator 200W dual output stator. I wired the system myself using a heavy duty AC regulator, and heavy duty DC regulator/rectifier. I have all the standard parts such as front/rear turn signals, horn, running lights, etc... Everything is controlled form a standard handlebar switch.

I am having battery life issues. With my first batery, I put about 100 miles on the bike, riding it a couple times a week. After about 1 month of this, I noticed my battery was not holding a charge very well. If I turned on the key after 2 days or so, the running lights were dim, and the horn was weak. Once I fired up the bike, everything was back to normal as expected. Then after a couple more weeks of this, the battery became so bad that as soon as the bike stopped running, there was nothing left in the battery to run anything.

It got to the point where even when the bike was running, it was having a hard time running the turn signals and brake light. And when I would try any of the DC items (brake light, horn, etc..) while the bike was running, the AC headlight would become very dim, almost like it was shorting out.

I replaced the battery, and rode the bike 2 times. Then I stored it for about two weeks. After those two weeks the new battery was already dead.

So now I've traced all the wiring and everything seems to look good. I installed a new temporary battery and checked to see if there was any current draw with the ignition switch off. My DMM wouldn't even register anything in the uA range. And once I turned on the running lights and used the signals and brakes, the current draw was exacty what I would expect. This was all done with the bike not running.

I checked the stator, and there is around .4-.6 ohm resistance at each output. I checked for shorts between the coils and there were none. The main wire from the stator had about 7.5K resistance to ground.

I checked both regulators and there were no shorts. I went through the handlebar switch and everything checked out perfect.

Now I am not sure what to do. The only thing I have not checked is to see what the charging voltage is at the battery with the bike running. I need to put things back together again to check this.

Is it possible that the batteries are overcharging and destroying them right away. Possibly causing internal damage to the battery which would cause them to discharge.

The one thing I can not make any sense of is when the battery becomes very poor, trying to pull power from the DC side is causing my AC side to almost short out. I do have some relays for my hi/low beams which are controlled by the DC side, but I checked these for shorts and there were none.

The AC side is completely isolated (ground and power) from the DC side. On the AC side, I have an AC regulator wired in parallel to the stator (white wire going to yellow, and green wire going to brown). Then I have the brown wire running to the GND of my headlight bulb, and the white wire running to the inputs of both relays. The output of one relay goes to the high beam and the other to the low beam. Then the headlight switch controls the relays from the 12V DC side. I don't see how a dead battery could be affecting the AC side.

I'm just trying to state everything I checked in hopes that someone can come up with a suggestion that may help me figure out what is going on.

Thanks.

[creeky]

It sounds like the regulator/rectifier might be the culprit. Check the alternator voltage output at various engine speeds.

[Jeff@TheQuadShop]

You may have already done this but everything that is powered by DC must ground through the negative side of the battery. Nothing DC can be grounded to the frame.

[DSTerry]

Actually, my DC ground (negative battery terminal) is tied to the frame. But my AC is isolated from the frame.

I used the existing GND connectors comming from the factory wiring harness to hook up all my DC grounds. Looking back at the factory wiring diagram, I see that the ignition coil and CDI unit are also tied to this common frame ground. Could this be a problem.

What is the main reason for not wanting to tie the DC ground to the frame?

Thanks.

[DSTerry]

I'll check the output voltage of the regulator once I put everything back together. I spoke with Ricky Stator and he mentioned the same thing. I may be destroying my battery by charging it with to high a voltage, or to much current.

I may build a simple current limiting circuit so I can match the charging current with the battery specs. I guess some of these rectifier/regulators can source a lot of current, and the battery will take whatever it can get.

I also spoke with a technician at PowerSonic (this is the type of battery I am using). One interesting scenario came up which may be my problem.

When I am riding the bike, it is always drawing about 1A (8W tailight, 2W front running light). Then whenever I hit the brakes and hold it on, thats an additional 1.5A for a total of 2.5A. This battery is rated for about a 2A draw for 15 min down to 9V (or 850mA draw for 1 hour). Being an SLA battery, they are designed to charge slowly. So I may simple be discharging the battery faster than it can charge. And on top of that, if I am discharging the battery quickly, it will try and suck a lot more current than it should to stay charged, causing internal damage. This battery has a maximum charge current rating of 600mA (datasheet stated 360mA, but technicain said 600ma). I'll have to wire in a meter to measure the charging current while the bike is running with various lights turned on.

Since I typically only do short 5-10 minute rides once or twice a week, this could very well be the case.

Now the only question with what I stated above, is how much current actually comes directly from the charging system? The lights are most likely just drawing 1A from the charging system, not necessary directly from the battery. I really need to figure out how much current this regulator can source, or make sure it is sourcing enough to run the lights without having to depend on the battery for supplemental current.

What have others experienced with charging SLA type batteries? Or are these just not a good choice for this type of application?

[creeky]

I gave up on SLA batteries a long time ago, I have much better results and service with nimh batteries from this scource www.batteryspace.com look under "robot batteries".

[DSTerry]

I was thinking of going that route. I was worried about charging the NiMH batteries. I have built my own battery packs using these batteries before for my RC car stuff, but I always have used a dedicated charger that will turn off when fully charged.

Do you use or do anything special to charge these batteries?

[Beyond The Pale]

Most of the dual sport kits use a 12V NiCad made of 10 AA cells. NiMH should work as well, but are not quite as robust as the NiCads. The good side is that the NiMH has 2x the amp hours. Normally NiCads and NiMH are not used in a constant voltage charging situaton. I have not had good luck with long life with these batteries, but they usually last for a year before going bad. Most others have better luck than I do with them.

I have the Baja Designs DS kit on my bike and it has no special circuitry other than the AC to DC regulator. There is nothing to limit charging currents. Perhaps that is what is killing the SLA. A larger amp hour SLA might fix the problem, but they are big and heavy.

If you are going to solder up your own pack, try and get batteries with tabs. Heat can kill the seals on the cells. The good thing is that AA cells are relatively cheap.

[creeky]

I had a two year old 750 mah nimh battery pack in my '01XR250. The bike sat in the garage for 3 months without being started, battery was still up and blew the horn with the lights on without dimming the lights. I had replaced the stock regulator with a regulator/rectifier when I installed the dual sport kit, the stock alternator kept the battery charged up just fine.

[DSTerry]

I'm going to check my regulator today and if it all looks good I'll give my sla one my try since I just bought a new one today. It was only $15.00 so I am not to worried about it. If I still have a problem, I may go with my own pack. I could easily do a 2300mAH with 10 AA which would be almost twice the power of my SLA.

My regulator/rectifier is a 200W unit. So it is easily allowing all 100W of the stator to go towards the dc side. Potentially the battery could be seeing 8A or so of charging current, minus the 1A for the lights. But that would be worst case scenario if the battery is very low and need to be charged. If the battery maintains a nice high voltage, then it should draw very little current. But that little SLA does seem to discharge pretty quickly. I'll keep an eye on it and see what happens over the next month or so.

Thanks for all the good advice.

[DSTerry]

Looks like my regulator/rectifier is working just fine. With the bike running above idle (guessing around 2000rpm or so), the battery voltage jumps up to 14.9V. I thought it might be a little high, but the battery can take up to 15V safely.

When I revved it a little higher, it slightly dropped down to around 14.75v.

Bikes ready to start riding again, so I'll see what happens.

[Jeff@TheQuadShop]

Actually, my DC ground (negative battery terminal) is tied to the frame. But my AC is isolated from the frame.

QUOTE]

This is your problem, you need to have all your DC negatives going to the negative side of your battery. Do not ground the battery to the frame.

[DSTerry]

This is your problem, you need to have all your DC negatives going to the negative side of your battery. Do not ground the battery to the frame.

Could you explain why it is not recommended to ground the negative side of the battery to the frame if the AC side of the system is completely isolated from the frame? What would one expect from hooking a system up like this?

The wiring diagrams that I have looked at from baja designs show the negative of the battery connected to the frame.

I installed a new SLA battery once again, and I went about 60 miles before the battery completely quit. It looks like the battery is being damaged because it only reads 10 volts now. Almost like one of the cells is broken.

I checked my regulator again and it never goes over 14.5V. At idle it is around 14V. I'm going to try a NIMH pack next and see how long it lasts. I've gone through the whole wiring system and everything looks fine.

I'm curious if others have had any problems hooking up the negative side of the battery to the frame ground.

Thanks.

[exaresix]

Just do what Jeff says. I went through the same process. Do NOT ground through your frame. Ground only to your battery. Check out this thread.

https://www.thumpertalk.com/forum/showthread.php?t=536600

[Beyond The Pale]

I'm curious if others have had any problems hooking up the negative side of the battery to the frame ground.

Thanks.

When I got my XR600 it had a Baja Designs kit already installed. It has the negative side of the battery connected to the frame. The only time this is an issue it with the older bikes that had on side of the coil connected to the frame. On those bikes you would have to float the DC ground from the frame.

As far as I'm concerned it's best to use wires for the ground and not rely of the frame, but there is no harm in connecting something to the frame.

I bet it is that higher voltage that is cooking your battery. Lead acid batteries will fry if the voltage stays over 14.4. The NiMH or NiCad will take a little more. NiCads are a little tougher than NiMH. There are some NiMH's that are designed to be overcharged and not fry. A surplus place All Electronics has some. They are 1100mah and AA sized. The part number is NMH-110 an NMH-110T with solder tabs. Get the tab ones unless you have experience with soldering straight to batteries. It is easy to damage them when soldering to them.

If you are trying to power the headlight from the battery, something with more amp hours will be needed. A 1 amp hour sized battery just isn't going to get that job done.

[DSTerry]

Thanks for all the input. Maybe I should quickly describe my setup.

I am using a 200W 'ricky stator' stator in the dual output mode. I have one side of the stator going to the 2 yellow wires on a 200W AC regulator and straight to my headlight. All the leads are floating and nothing is connected to the frame.

I then have the other side of the stator going directly to my DC rectifier/regulator. (Same one that exaresix has pictured in his thread). The green wire (I think that's what color it is), is going to the stock wiring harness where the old stator line was connected.

From my DC regulator, I have the black and red wires going directly to the battery, and then plugged into the 12V and GND locations on the stock harness. I also have the postiive side running to my new turn signals, handlebar switch, and relays (for my headlight) with new wires. So in reality, the only place I have my ground connected is into the stock wiring harness ground. Though this ground is grounded to the the bikes frame when I measure with an ohm meter. Everything is correctly fused for safety.

My regulator does put out a constant 14.5+ voltage, and I know that is pushing the limits of the SLA batteries. I'll check out All Electronics, I've ordered from them before. Thanks for those part numbers.

cleonard - when you say one side of the coil connected to the frame, do you mean the stator coil? Because my 'ricky stator' stator is not like this.

[Beyond The Pale]

cleonard - when you say one side of the coil connected to the frame, do you mean the stator coil? Because my 'ricky stator' stator is not like this.

I guess I wasn't too clear. I am setup almost exactly like you are. I have a Baja Designs dual coil. One AC regulated to the main headlight with a 90/100 watt H4 bulb.. The other coil is wired up for DC just like you describe. ou can never have too much light.

I don't have a battery right now. I left the switch on one day after riding and that killed the battery dead. I had a battery made up of those All Electronics cells and it was working for six months before I killed it. I've got more of them and I just need to solder them up.

[DSTerry]

I'll build me a pack with some NIMH batteries and give it a try. If I kill those in 2 weeks (as I have my last 3 SLA batteries) then I'll go back to the drawing board.

I assemblied my own DS kit, but I am using a baja designs headling and 90/100W H4 buib also.

Thanks.