Fried my CDI?

Dear friend how can I verify the cdi n the magneto are ok

the CDI & coil make a spark at the right time - if you can see the spark or feel it in your hand, then both are working at making the spark - if the timing is bad, there is no way to test that except with a real CDI tester or by trying a new CDI
 
Just because ya GET a spark don't mean it's a hot enough spark. A weak coil will fool ya every time. Sometimes you can get it running on a weak coil, but it will run like CRAP. Most of the time I dont bother even testing a coil, They are only $12 so I keep an extra on hand and switch it out. If it runs better, It was the coil,LOL. 99.999% of the time in a weak or no spark situation, IT'S THE COIL.
Big Red.
 
99.999% of the time in a weak or no spark situation, IT'S THE COIL.
Big Red.

I recently had a misfiring issue. I swapped out the spark plug (NGK-B6HS) first to see if it made a difference and it didn't. Then I swapped out the plug wire and boot (stock) to an automotive plug wire and boot. Those plug wires like to break at the wall edges and I end up having to dig them out...grrrr! No change. I then swapped out the stock cdi with another stock cdi and voila! That is the first cdi that has gone out on me in the four years I've been mbing. I like to keep everything stock if I can, save for the spark plug, hub adapter with sprocket, and chain tensioner. However, that automotive plug wire and boot really make a difference and I can tell the connection is so much better. Every time I look for a Jaguar cdi I can never find one and how much of a difference does it make? Also, when I pulled the first spark plug to troubleshoot I noticed it was the undesirable-black as tar-looking color. That means I am running rich, correct? Rich meaning too much fuel to air ratio. My idle screw is in all the way but if I back it out it doesn't idle at all. My needle is in the second from the top position. If I had an air leak wouldn't the color of my spark plug be ash white? My thought is that my oil (Amsoil Saber Professional 2-cycle) to gas (Circle K 87 octane) ratio is too high (approx. 35:1). I don't ride WOT hardly ever. I keep it at 80-90% (22mph-26mph) throttle so I have a little extra when needed. I live in a warm, dry climate with some moderately steep hills. I have a 66cc, 2-stroke, well broken-in (1800 miles), stock carby, stock muffy, stock head. She runs good but I would like her to run great. What do you guys think I need to do in order to get that sweet chocolate brown/tan color on my spark plug? Any advice would be greatly appreciated. Thanks mbers!
 
Well, I just finished the last of my 35:1 mix and mixed up a batch of 45:1. I checked my spark plug and it was a little lighter than before. It was tar black because the last 12 miles was when the CDI was misfiring so the spark was intermittent which resulted in the dark color. Regardless I still have a little bit of fuel build-up at the bottom of my muffler but not enough to drip. It should ideally be dry, shouldn't it?
Thanks for all your help guys, you're all wonderful.
 
I took her out to the gun range today and she ran quite well. She doesn't really warm up though until about a mile before she does 25mph. Could just be because of an upgrade and headwind though. The idle sounded fine and the throttle response was sufficient. I increased the average mph to 19.3 and the max to 27.9mph. After a total of 21 miles today I pulled the plug and it was tan and dry, the muffler also had no oily residue at the base. I think I have found the sweet spot as far as my fuel ratio goes (45:1). I am pleased with my bike and have finally reached Elysium, so to say...of course until the next inevitable problem arises. Thank you for your patience Jeff, you've earned it. Sometimes the best advice already exists within all of us. Mileage update-1,845
 
hey guys just wanted to add that a customer came in today with a non starting engine, i knew it was the cdi, so off i went to examine, dc.ed the killswitch and tried , no go, then changed the magneto coil, and wallah!!!! once again the 2 stroke comes back to life....varooooommmm!!! also blew a gasket the other day , head bolts came loose but didnt tightten them down before riding again and so boom,,,the head gasket went, and thats it.... changed out and off i went again !!!! I TRULY BELIEVE THAT THE MAGNETO COIL, IS THE CULPRIT MOST TIMES WHEN YOUR ENGINE WONT FIRE, BE IT NEW OR NOT, SOMETIMES MOISTURE WILL FORM WITHIN YOUR CASE OR EVEN THE OUTSIDE AND BECUZ YOUR WIRES RUN DIRECTLY TO THE COIL , IT WILL ALMOST DEFINATELY LEAD ANY MOISTURE ALONG THE CABLE, WHICH IS DIRECTLY CONNECTED TO THE ENGINE VIA blue black and white cables... thisis very imprtant to keep dry, once wet your engine wont fire ever again !!!!! if you have spark but wont start or fire, then check this immediately ..... if you didnt know this it can really do your head in badly..... no joke!!! spark is spark, question is is it strong enough, and is it constant ? just cux you have soark doesnt mean its strong enough to ignite engine...../
 
I am pleased with my bike and have finally reached Elysium, so to say...of course until the next inevitable problem arises.

That's exactly how it is: moments of pure pleasure interrupted by periods of mediocre engine performance, interrupted by periods of total frustration that takes you to the deepest depths of utter despair.

Climbing your way out of the hole, with grit and determination and a warrior like spirit, to find and conquer the gate keeper of Elysium shows the true strength and robust nature of the male spirit that knows only one way of approaching an insurmountable problem: claw your fingers into the situation and hang on for the ride; fighting like hell to tame the vicious beast and bring it into order to teach it civility.

Crikey, that almost sounds like my last relationship, only that the engine needed a lot less effort to make it behave with an acceptable level of civility.
 
Here's the deal; a weak spark system can produce a spark when the plug is out of the engine, but not when it is inside the engine. That is because the higher pressure requires more voltage to spark the gap. Another reason to switch to an aftermarket CDI/coil when increasing the cranking pressure.

Many "bad" magneto coils aren't bad at all. Where the screws contact the metal needs to be sanded clean, that's all.
 
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