1984 200ES CDI Replacement, MythBusted..

[86T3]

How much voltage should the exciter and at the coil? The manual has nothing about this.

[kb0nly]

The exciter is 10-30v depending on engine speed, i forget what the voltage is from the CDI to the coil but its over 100v i think, its been a while since i measured it on one. Just set your meter to AC voltage and put the negative lead to the frame then the positive lead to the wire from the exciter, crank and see what you have, if you have voltage there then go to the pulse generator and check the output, this is tricky with a digital meter as its quick pulses of AC voltage. An old school analog meter so you can watch the needle jump or an old style test light with a bulb and not an LED in it works also. If you have output from the pulse generator then check the input at the CDI just to double check and then check the output of the CDI which is the wire going to the coil. The test light works best for checking for the pulses after the pulse generator and the CDI.

You just have to chase the voltages through the system until you find where it stops. If you have voltages everywhere and pulses but still no spark then its got to be the coil, plug wire, plug cap, spark plug. If you have spark but still no fire, check your timing and valve adjustments. Also if you have spark how good is the spark? If its yellow or orange its pretty weak, if its blue or bluish white then your fine.

Weak spark on these is generally due to the CDI not ramping up the voltage enough for the coil. Sometimes its a weak coil, but i can't recall ever replacing a coil that just failed, i replaced one that got broke one time, but generally they are pretty bulletproof. There is the chance that the CDI worked on your buddies because the situation is different, compression differences that let it run with weaker spark, etc. I would still try replacing the CDI with a new one as well, those old CDI's get pretty weak with age due to the aging of the components in it.

[86T3]

I have no spark at all. It started as an intermittent problem. I rode it for a minute, parked it to adjust the brakes and then it wouldn't start. no spark at all. Next morning, fired right up. Ran it for less than a minute, shut it off to mess with the rack, then it wouldn't start. no spark. Next morning i check it and it pops twice then nothing. I just checked my coil at my buddies and it worked fine also. I'm going to follow the voltage now and see where it leaves off. Sorry to steal your thread but thanks immensely for the help

[86T3]

The teeth off the starter gear took out the coils. The previous owner showed me the old starter with the teeth ground off, i never thought that they could get into the crank case. looks like i need to do some more parts shopping

[kb0nly]

Dang, so i take it the stator wasn't putting out much voltage due to the damage? I have seen them ohm out ok but still be damaged so no surprise.

Its all a shared oil sump so anything that falls off ends up rattling around, and the flywheel being a big magnet usually attracts any metal that ends up in the crankcase. When i pulled mine apart to fix the one way starter clutch, 84 200ES, i found some metal filings on the flywheel being held by the magnet, it was from the chewed up rollers in the one way clutch. Probably good the flywheel got those filings, they couldn't damage anything else!

A stator for an 85 isn't that hard to find, check eBay. There is also a couple companies that make an updated higher output unit as well. I forgot the 85 had an all in one stator for charging/lights and ignition, the 84 has a separate exciter and alternator coils.

[GTO]

GOOD NEWS!!!
My father is at our holiday place at the moment and he installed the chinese CDI I bought the other day into one of our 200es trikes.
I am happy to report that he says the spark has definitely improved.
Now I can go ahead and buy some more CDI's

[kb0nly]

GOOD NEWS!!!
My father is at our holiday place at the moment and he installed the chinese CDI I bought the other day into one of our 200es trikes.
I am happy to report that he says the spark has definitely improved.
Now I can go ahead and buy some more CDI's

Awesome! The stock CDI is just old enough to be going bad on most of these, so i think it will be very common to see these failing.

[86T3]

Great news!

[GTO]

UPDATE:
I managed to get to our holiday place this weekend and the trike that my father installed the chinese CDI runs beautifully and at last I have a 200ES that has the correct brown colour on the plug electrodes(they were always black like they were running rich but as I have always thought it was a weak spark causing this).Once my brother gets back from Houston with the additional CDIs I will have another 3 200ES that run properly!

[kb0nly]

Sweet! I was hopeful that your problem would be solved. Mine really runs good now after running a couple tanks of gas through with some seafoam mixed in, i think the exhaust valve was bad carbon'ed from fouling before replacing the CDI. The first tank of gas with seafoam mixed in it was blowing black smoke out the exhaust so bad it left a black circle on the front of the small trailer i pull behind it. After the first tank full the smoke stopped but i had enough to treat another tank full so i figured why not, it would get a little black smoke on revving up for a few days then it cleaned up, no more black smoke and it definitely revs better. You might want to think about running some cleaner through as well, couldn't hurt if you were fouling that bad like i was!

[GTO]

I have rebuilt all 4 engines as well as new carb rebuilt kits in all of them, so thats why I was pretty sure it was a weak spark issue.
Funny thing is after a complete strip down and rebuilt on each the CDI's started failing one after the other.
It was driving me crazy especially considering the money I had put into them.
One of them now has no spark with the electric start but sparks with the pull start?(spark is pathetic though compared to the one with the new CDI)
Also they all seemed to have a slight misfire at higher rpms but the one wih the new CDI now doesn't have the misfire anymore!

[kb0nly]

Most likely what happened is you rebuilt them bringing the compression back up to the point that the weak spark was no longer able to properly fire the plug.

The electric start vs pull start problem i think i have figured out as well!

The pull start gives a longer pause between pulses, looking at a test light connected to the pulse generator output and pull starting it i couldn't get it to flash as fast as it would with the electric start no matter how hard and fast i pulled. You would think that this would mean that electric would work better than the pull start on a weak CDI but its exact opposite. The longer dwell time of the pulses when using the pull start allows the weakening components in the CDI to catch up, mainly the capacitors is my guess, so that it gets sufficient voltage built up to fire. With the electric starter its a quicker on/off cycle that it can't keep up and only throws an occasional spark.

Again this is only my hypothesis, but watching a test light on the output of the pulse generator and a spark tester inline with the plug this is the conclusion i came up with.

[GTO]

Most likely what happened is you rebuilt them bringing the compression back up to the point that the weak spark was no longer able to properly fire the plug.

The electric start vs pull start problem i think i have figured out as well!

The pull start gives a longer pause between pulses, looking at a test light connected to the pulse generator output and pull starting it i couldn't get it to flash as fast as it would with the electric start no matter how hard and fast i pulled. You would think that this would mean that electric would work better than the pull start on a weak CDI but its exact opposite. The longer dwell time of the pulses when using the pull start allows the weakening components in the CDI to catch up, mainly the capacitors is my guess, so that it gets sufficient voltage built up to fire. With the electric starter its a quicker on/off cycle that it can't keep up and only throws an occasional spark.

Again this is only my hypothesis, but watching a test light on the output of the pulse generator and a spark tester inline with the plug this is the conclusion i came up with.

Thanks very interesting, the CDI in this trike does start the others though with the electric start.
I am sure I read some where that there is a neutral safety for the electric start so that it cannot be started in gear with the electric start maybe this could be the problem?
This engine was starting fine with the electric start before I removed it a few months ago to change a cam chain after I reinstalled it no spark with the electric start?

[kb0nly]

Does the neutral indicator light come on? Check the neutral switch terminal, the gray wire to the nut type terminal above the sub-trans shifter. It should be grounded, continuity to ground on that terminal, when in neutral. If not then its either not in neutral or the neutral safety switch is bad. If you want to test it otherwise you could make sure the shifter is in neutral then clip on a jumper from the terminal to a frame ground to keep the gray wire grounded, the neutral indicator should come on and the electric start should work as well as the ignition.

[GTO]

Does the neutral indicator light come on? Check the neutral switch terminal, the gray wire to the nut type terminal above the sub-trans shifter. It should be grounded, continuity to ground on that terminal, when in neutral. If not then its either not in neutral or the neutral safety switch is bad. If you want to test it otherwise you could make sure the shifter is in neutral then clip on a jumper from the terminal to a frame ground to keep the gray wire grounded, the neutral indicator should come on and the electric start should work as well as the ignition.

Neutral Indicator light is working.
Isn't it the green wire with red tracer?
Grey wire is for the reverse is it not?