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Urgent question (stator assembly/CDI/rotor)

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2003 DRZ400S

The mechanic here in Venezuela replaced my stator with one of similar size but another set of cables/connectors. He then replaced my CDI with a 'universal' one, smaller and with only one 8pin connector. Because the bike would not run, he had the idea of GRINDING away the smaller one of the magnetic (?) strips on the outside of the rotor..

It was miraculously starting better as ever and ran fine for a small test drive!! Second drive started to hesitate and now it is difficult to start, hesitating when throttling and dying out..

Does this procedure make ANY sense to anyone? Is there any hope that this could possibly work? Or is the only solution now to get the right stator and a new rotor?

Any insight is appreciated!

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Venezuelan technology, I love it. The procedure makes sense to me. Would I do it this way, No. If it's an emergency take it back to him. It's obivously not his first time working on a bike. In the States a mechanic would tell you, "your screwed." It sounds like to me that he is trying to get you back on the road. It all depends on how easy it is to get the correct parts and how much time you have, I guess.

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Was trying to spare the details..it's urgent because i have till tuesday to leave the country on the bike's 'visa'.. The mechanic and i both knew that..he really put an effort in it..trying to work fast for me..he had the feeling it could work..and i just don't know enough about the electrical system.

so it looks like this could really never work?? it then only leaves me trying to bribe officials for me to extend my permission,, nationalise the bike or transporting it to the border and push it over..

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That is a hard question to answer. Previous answer was right - in the US we would not try to re-engineer or improvise to that extent. We would just buy the correct fitting parts.

But - The basics of an ignition are rather simple and improvise can work. There needs to be a ignition coil (transformer really) to create a high voltage spark and there needs to be a way to fire the coil at the right time. So yes a pick up coil of come kind (and the DRZ has one) to provide a firing signal, a signal processor that can interpret the signal (CDI type or transistorized switching circuit) and a ignition coil compatible with the switching circuit and you have it.

2 basic types. CDI, a capacitor is charged and the switching circuit fires the stored energy into the coil to make the spark (fires on rise). Or the coil is charged from the 12 volts DC and the switching circuit interrupts the circuit and the field collapses making the spark (fires on collapse). So the whole trick to making an improvised system work is compatible components. I can see making a system from a car or other motorcycle work on a DRZ if your mechanic has the technical understanding and skills to make it work.

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aha..

The mechanic changed the ignition coil to one that would be compatible with the new CDI. He also surely knew how to connect the CDI in the new situation.

Can it then be true what he suggested that the new CDI uses only one signal and that the orginal CDI takes two? (and therefor grinding away one magnetic strip..) Or is that too easy thinking?

Isn't it al least interesting that it was actually working perfectly for a little while?

I have to add that he noticed that the current on the battery was too high when throttling..suggesting to only run with headlight on. Turning the headlight on was actually helping the situation, but later it started hesitating again. Does this make sense to anyone??

Can it in any way be possible that he actually created a well working ignition system, but that in another way the new, and maybe noncompatibel, stator is creating too much current, interfering the ignition system?

sorry if this is not making sense..

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Yes it is all possible and it does sound like your mechanic kinda knows what he is doing. Probably more about improvisation than I do. The more common ignition uses only 1 magnet for pick up pulse so it does make sense to remove the other magnet. I would guess you no longer have a CDI system but now have a conventional system with a transistorized signal amplifier and switching circuit. Yes I would expect the coil would need to be changed to a standard type coil. I have to wonder what if any it has for an electronic advance curve and what the static timing is.

I would experiment with running the motorcycle on the battery only. Stators don't really put out too much power but it is quite possible the Suzuki rectifier/regulator might not like the "new" stator and is not regulating properly.

Current is dependent on load. If something draws too much current there is a problem with the component. The battery or stator does not "push" too much current. It supplies the demand. BUT over voltage can be a problem. If the stator (power generating system) is not regulated properly, voltage can rise and damage or cause malfunctions. Running better with the headlight on sounds like a voltage problem. As the current demand goes up it draws the voltage down. So try it running on the battery only. The battery will only put out battery voltage (about 12 volts) and no more.

Good luck with this.

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so there is hope! that is great information!

Will try to figure out how to run on battery only. (disconnecting stator?) If it then does run smooth, we can try to change the regulator/rectifier on monday, what could fix the problem!? Then the stator, black box and regulator/rectifier would all be compatible. Let's hope so!

thanks a lot!

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so there is hope! that is great information!

Will try to figure out how to run on battery only. (disconnecting stator?) If it then does run smooth, we can try to change the regulator/rectifier on monday, what could fix the problem!? Then the stator, black box and regulator/rectifier would all be compatible. Let's hope so!

thanks a lot!

Only the AC side of the stator (three yellow wires on the OEM stator) You need the ignition pulser part of the stator to trigger the OEM CDI.

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Good news!

Running on only the battery makes it run perfectly! Connector in: hesitating, Connector out: all smooth.

First thing tomorrow morning getting a new regulator/rectifier..

If it runs like expected with that new regulator/rectifier 'Noble' has probably saved a nice DRZ from ending up at the Venezuelan dump! Hallelujah to you guys and thumpertalk!

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I would like to see you do some voltage testing now that you know the improvised system is voltage sensitive before you jump to a new regulator/rectifier (RR). Battery only, the system is going to be around 12 volts. System voltage with a good functioning stator and a good functioning RR will be 14 to 14.5 volts. I would think 14 - 14.5 volts would be ideal and should be the expected range for any 12 volt DC system. BUT you don't know the end result until you try it.

Do you know what was used for an ignition coil? Some coils like a resister in the power wire.

If nothing else, you can run quite a while on battery only if the lights are disconnected. If you strap a car battery on the back seat, it will probably run several days between charges.

Thumbs up to your local mechanic. A master of improvisation.

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Back again! I have been on the road for 2 days and made it to Colombia!! Which means a new permiso for 60 days. Safe!!

I really appreciate your help Noble and, although the bike is not at the Venezuelan dump thanks to you, the problem is not yet solved completely.

After your advise and finding out it runs fine on just the battery, on mondaymorning we installed a new RR. It was not a specifically chosen regulator, just 'one with 3 yellow wires'. The mechanic checked system voltage and i heared him say '14'. It seemed to work perfectly and we drove for 4 hours, without the light on or anything.

Next morning we drove of (actually the starter engine wouldn't kick in for some time, but fortunately after like 5 times it came to life, also it was hard to start i had to give small shots of throttle..), but.. after like 5 minutes on the road it started to hesitate suddenly and backfire. I slowed down, disconnected the connector of the stator (AC). This helped. I then turned the headlight on, connected the connector again and drove at around 70km/h (40mph?) all the way to Colombia. It seemed to start hesitating on high rpm's. Didn't know how long a bike would run without charge, so had to do it like this.

When safe and sound (what a relief!) at my hotel i did a testrun without the luggage. It's exactly the same problem as before the new RR. Starts hesitating when throttling, but turning the headlight on (and also when disconnecting AC side stator) makes it run smooth. So the new RR seemed to have only 'worked' for one day, but next day it seemed the same problem was still there.

So what can be the problem?? Why did a new RR work for only one day? Both time the problem came on the second drive on a cold engine. Can it be that it's not the RR but that the combination rotor and uncompatible new stator is the problem?

I do not know what type of ignition coil it is. Will try to ask for a resistor at a local shop here. Maybe someone there knows a mechanic with a lot of electrical knowledge. Will think more and check voltages! If someone of you has any idea, i appreciate.

A long story..but there is no other way. Will come back to internet in the evening and go and try anything i can.

Anyone that has any idea..i would appreciate. THANKS A LOT!

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Update.

Is this system maybe burning my RR?? Aren't high voltages and a failing ignition on high rpm's not symptoms of a burned RR? That would make sense because the problems didn't immediately start, but rather on the second run. Maybe by shortcuts or because the new stator or module is connected incorrectly?

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I may have been incorrect when I said the stator can not put out too much current. This is generally true for any specific system. Electrical power generation, commonly known as an alternator, consists of stator coils, magnetic field, rectifier, and a control circuit (regulator) There are 2 general types of alternators - those that use electro magnets (car types) and those that use permanent magnets (most motorcycles). Within any any specific type, the alternator system is rated for output in amps or watts. Cars in the 60 to 150 amp range, motorcycles in the 100 to 300 watt range. (volts times amps = watts). Control circuit for a electro magnet (excited field) type alternator controls the strength of the magnetic field which controls the power output of the alternator. Control for a permanent magnet type, the regulator shunts the coils to reduce output. Permanent magnet alternators are designed so the power generated is close to the power needed to run the vehicle because of the limited ability to regulate output. (A DRZ400 is designed to run with the lights on all the time)

A DRZ400 motorcycle has a 3 phase permanent magnet alternator rated 200 watts (about 14 amps at 14 volts). The DRZ rectifier/regulator is designed to rectify and regulate the 200 watts. Since you now have an improvised non-standard stator, I do not know its power output. It could be more or less than the original 200 watts. Alternator output also will vary with engine speed. So if your improvised system is putting out more then 200 watts particularly at higher engine speeds (throttling up), it could put out too much current for the RR to handle causing the RR to over heat and fail.

Do you know anything about the original application of the stator? (what the power output might be)

Do you know any thing about the power capacity of the replacement RR? (ratting in watts)

Do you have the ability to test system voltage? (a failed regulator will allow higher than 14.5 volts) The rectifier part of a RR can also fail permanently shunting the output or allowing AC past the RR. Either type of failure is bad.

I always carry a voltmeter (multimeter) with me because the electrical system is probably the most unreliable part of any motorcycle.

When it comes to selecting a replacement RR it should be rated for the maximum output of the stator. Since you don't know that answer, I would advise a RR for 250 watts or more. Any solid state RR from any motorcycle that uses a 3 phase permanent magnet type alternator can be adapted to the DRZ. Some RR have 5 wires and some have 6. 5 wire are - 3 AC inputs from the stator and DC pos and DC neg output. 6 wire are - 3 AC inputs from the stator and DC pos and DC neg output plus a sense wire. The sense wire senses battery voltage and needs to be connected to the battery thru the ignition switch so it is disconnected when the key is off. (5 wire RR sense battery voltage internally. 6 wire RR sense battery voltage thru the sense wire)

Probably no need for a resister to the ignition coil. The problem continues to sound like over voltage to the ignition control circuit. Try to do some voltage testing to isolate the problem.

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Just had another idea. A rough form of power regulation is to add or subtract generating coils depending on the load to the system. In the 60's and 70's when motorcycles had light switches it was common for the switch that turned the lights on/off to also turn some power generating coils on/off.

So you could experiment with disconnecting 1 of the 3 stator wires. Experiment with running with the headlight on or off vs 2 or 3 stator wires connected. It also might make a difference which of the 3 stator wires you disconnect (because some regulators do not regulate all 3 of the phases)

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Hi Noble!

I was on the road again and moved to a bigger town. My bike actually has a switch for light AND for the fan (it has no `dashboard` or anything, all improvised work..). With both the light on and the fan it runs perfect! (so definitely the voltage is the problem) So i am at least safe to travel, but of course don`t want to have my fan on all the time..

Have been thinking a lot, but unfortunately have not internet all the time. Your information is VERY useful. I don`t know the output of the stator, but will get a multimeter tomorrow. I will test everything and go experiment with the stator wires. Will find it eventually!

Having thoughts about if the regulator is permanently failed (burned¿) or it just fails from a certain stator input? I have the feeling the regulator has failed permanently (burned¿), because it failed not on the first ride. Don`t know if it is possible that a regulator keeps working partially though. That would then mean the new system destroyed both the original suzuki RR AND the new one. Will try to get an idea of stator output and the capacities of both the RR`s!!

For possible causes other than the new stator and black box i can only think about the little earth wire at the negative battery terminal. A while ago it came loose and i connected it at the terminal screw. Never had problems with it though as far as i know. Maybe not connected enough and therefor the regulators both burned?

More soon!!! THANKS again!

Edited by phendrixx

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The small earth wire near the battery should not be a problem. The original wire harness is connected to earth 2 places - the small wire to the battery and a ring terminal at the ignition coil mounting bolt. The fat battery cable is connected to the motor and the motor is bolted to the frame so everything is grounded (earthed) by those connections. However, it never hurts to have some redundant earth connections. Good ground (earth) connections are important to function of the overall electrical system and to function of the RR.

In general electronic devices either work or they don't. It is possible for a RR to be intermittent but usually once failed it is failed permanently.

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