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plug gone but still poor voltage

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Hi guys

Today I removed the plug that connects the stator to the battery as it gave me problems on a trip. I just soldered the wires together so I know the connection is now 100%. But with a 55w bulb my battery still drains when I ride in traffic :thumbsup: I had the multimeter on the battery and at idle I get 12.8 - 12.9 volt and with some revs it goes over 13V and then climbs from there without the light being on. But if the bike stays at idle (with light on) the voltage just starts to drop slowly almost as if the stator cannot keep up. Will it help if I use a relay ? I've also decided to run the wires for the light direct from the battery. Is a halogen 55W bulb too much for the DRZ ? I have no other devices drawing power from the bike.

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55 W draw should be no problem at all for the drz, even at idle. That is what the stock S headlight on low beam is.

Are you sure you have a good battery in there?

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If you have not already seen this, here is the latest version:

Here is the full procedure:

The electrical system is composed of 5 main components:

1. AC generator (the stator and magnets in the flywheel)

2. The rectifier

3. The regulator (the rectifier and regulator are combined in 1 box but function independently)

4. The battery

5. And the wires that connect everything.

First things first - check the charge voltage at the battery. Battery needs to be fully charged. Running 3000 rpm you are looking for 14 volts or higher. If voltage is low, start troubleshooting the system

Stator and wires. The stator is easy to check and the source of all power so check that to verify it is good. Check short to ground, coil resistance and running AC voltage of all 3 phases as described.

It is very important to check all wires and system ground wires. You have to be systematic and comprehensive. There are no secrets or short cuts

Check the 2 pin plug from the RR. From the battery, trace the small red wire and the small black wire to the first connector. Check those 2 connections. They must be perfect. Check and replace the fuse. Look closely at the fuse holder. The fuse must be a tight fit. Check the 3 pin connection between the stator coils and the RR. Any heat tint or melting of wires or connector plastic here or anywhere else is a problem.

Procedures:

1) Check all connections in and out of the regulator/rectifier (RR) 3 yellow wires and 1 each black (black has a white trace) and red. Trace the red to the battery and check all connections, the fuse and fuse holder and battery terminals. Now do the same with the black wire. You are looking for any signs of heating, loose or dirty or corroded connections. Fix if you find any. Test connections with your hands to feel for any heat (under load). Hot connections are bad.

2) Use a volt meter at the battery. This test needs to be done with a good and fully charged battery. Motor off key off - you should have 12.8 or more volts. Key on, lights on, motor off - around 12 volts is good. Motor running at idle - above 13 volts is good. High idle to around 3000 rpm - 14 to 14.5 volts is what you want to see. Suzuki says 13.5 is OK but that will not keep a battery charged. Many DRZ's will show the highest voltage at idle and the voltage drops as the rpm goes up. That is ok if it is above 14 volts. It is not really dropping but your test meter thinks so.

3) Low voltage - start by checking the stator coils. Unplug the 3 yellow wires from the RR. Motor off: check each yellow to ground. (The wires from the stator coils not the RR. We will check that later) No continuity is good, any continuity is bad. Now check wire to wire: Y1 to Y2, Y2 to Y3, and Y3 to Y1. You should see about .5 ohm resistance. Any open is bad, any continuity is good. Now start the motor and check the AC voltage output: Y1 to Y2, Y2 to Y3, Y3 to Y1. You are looking for about 60 volts AC at approx 3000 rpm. Exact output is not critical but should be about the same for all 3 readings and above 50 volts. Voltage varies with RPM. Make sure you use the AC scale. If any of the stator coils are shorted to ground, the stator AC voltage out-put can still test OK open circuit. But when you plug it into the RR it will not work because you have a common ground for both the AC in-put and the DC out-put. That is why you must do (and pass) all 3 tests.

4) RR testing - remove the RR from the bike. You can test the internal rectifier diodes. Put your digital meter on diode check and follow the meter test instructions. Check red wire to yellows wires then reverse the test leads. You will get no continuity one way and about .5 volt drop fwd continuity the other. Now repeat the test black wire to yellows. You should get the opposite results for no continuity and fwd continuity with a .5 volt drop. If you are not using a digital meter with diode test function, use a 12 volt battery and a low wattage bulb and test for continuity vs no continuity. There is no good way to test the regulator except by elimination of all other problems

More info, some redundant

Look at all the wires and connections between the RR and the battery. Both pos and neg. Look at the fuse and the fuse holder. Try a new fuse (fuses can go bad without going open) If you don't find anything, make a test connection so you can test voltage at the red and black wires right at the RR. You are going to have to improvise so you don't poke holes in the insulation which is always bad to do.

At this point, I always recommend to rewire the RR output direct to the battery. Use 14 gage marine grade wire and ring terminals. Cut the wires about 4" from the RR. (insulate the cut red wire to the wire harness) Extend the RR Red and Black wires direct to the battery terminals. Even if all the connections are good, this mod will give about .5 more volts to the battery.

You should be very comprehensive with checking all the wires and terminals and connectors. Suzuki uses small wires and small connectors and any sign of heating will cause problems. Ground wires are too often overlooked but are just as important as the pos feed wires. Something as simple as the small black wire from the battery to the harness can stop everything. That is the only place the loads (other than the starter) are grounded.

There is 1 more thing to check. That is current leakage. With every thing off, disconnect the battery neg. Connect a light between the battery and the cable. Should get nothing. If the light glows you have a big current leagage problem. If no glow, continue. Use the 10 amp scale and connect between the bat an the cable. If less than 1 amp go to the milliamp scale. You are looking for less than 1mA currrent leakage.

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Apreciate the replies ! I think I'll put my battery on the trickle charger again and then check the voltage. The battery is only about 4 months old. I changed the old one because of that dodgy plug that comes from the stator (now gone), it was never the battery but the connection that was faulty. Lots of things to check, so basicly I can take the wires from the stator and run them directly to the battery with proper gauge wires ?

PS what effect does this mod have on the fused system ? Will it still sense a short circuit ?

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The RR out-put to the battery will bypass the fuse which is common and prefered. All battery supplied and RR suplied power to the system will pass thur the fuse. In the original sysyem, RR power to the battery is fused but to the rest of the system is un-fused. This is undesirable. The re-wire is a better design in my opinion.

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Don't hookup the stator wires to the battery!

I think you meant rectifier/regulator instead of stator. AC voltage comes out of the stator. DC voltage comes out of rectifier.

I suspect that it is either a faulty wire harness or regulator/regulator.

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Not to spook a guy, but my RR died about 1500 miles into ownership. It can happen. Just stay systematic in your troubleshooting, like you've been. You'll get 'er.

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Don't hookup the stator wires to the battery!

I think you meant rectifier/regulator instead of stator. AC voltage comes out of the stator. DC voltage comes out of rectifier.

I suspect that it is either a faulty wire harness or regulator/regulator.

Yes I'm talking about the two wires (red and black/white) going to the battery from the regulater. That's the one that needs to go to the battery ? Another thing can a DRZ run on a drained battery ? Last time when this RR plug failed the bike began to cut out as the battery drained :thumbsup:

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Yes the drz can run on a drained battery, or even no battery at all (it would like a capacitor in that case).

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So why is it cutting out when the battery is dead? :thumbsup:

STATOR?

It was that plug from the RR, I fiddled with it at the side of the trail and the bike ran again until the connector gave trouble again which caused the battery to drain. Seems that the bike only got power from the battery until the juice ran out, it got nothing from the RR side. I've removed it and just solderd the wires. If that connection is good can the DRZ run with a flat battery in case of emergency ?

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Suposedly it will run without the battery, but it will be bad for the electrical system and it might run like crap.

Burned would be able to tell you exactly what it is.

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they run fine with a dead battery.they run fine with out a battery.its very hard on the electrics.you need a battery or capacitor.

if your bike quits running when the battery goes dead you have a bad stator.

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Yes, The bike will run from the RR. But if those RR Red & black wire connections are bad, you loose the power there so the battery does not get charged and the rest of the bike is also short on power so it may not run at all. With those wires soldered together it should run with no battery. If not, there is another problem, like a bad stator.

In the original configuration a DRZ will bump start and run with the main fuse blown (it runs off the alternator via the RR). With the "Free Power mod" the bike will not run with a blown fuse because now all electrical power to the system passes thru the fuse.

If you work systematically thru the full procedure, you will find the fault faster than the shotgun approach.

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