CDI horror story. Help please...

GoldenMotor.com

ddesens

Member
Jun 27, 2011
173
0
16
New Port Richey, FL.
Take the spark plug out of the engine. Snap it into the spark plug cap. Tape it against the head with masking tape so the end of the plug is touching bare head metal. Let the clutch out and roll the bike or pedal it in the dark. Look down at the head while doing this to see spark jumping across the leads on the spark plug.
 

crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
I looked at the pics - good news, the wire hookup looks right, bad news, you seem to have broken the top of one of your CDI units (but it may still work), bad news, you still have the nut on your magneto rotor, so how can you tell where the keyway is pointing at top dead center???

move MUCH more slowly, read the threads MUCH more completely - all the background info about ignition problems is here in simple explanations, with diagrams & pics, but some is spread over diff threads
 

zeroviral

New Member
Oct 20, 2013
21
0
0
Staten Island, NY
I looked at the pics - good news, the wire hookup looks right, bad news, you seem to have broken the top of one of your CDI units (but it may still work), bad news, you still have the nut on your magneto rotor, so how can you tell where the keyway is pointing at top dead center???

move MUCH more slowly, read the threads MUCH more completely - all the background info about ignition problems is here in simple explanations, with diagrams & pics, but some is spread over diff threads
Okay my CDI works just fine with the copper sticking out at the base. I get continuity throughout the circuit just fine...I can use another if I want to anyway. The copper wiring touching the plastic just loses some of the charge, but it's not by much. From 6.7 it drops to 6.4 when compare to the other CDIs.

Does the magneto rotor need that bolt to stay on? Or is the bolt itself useless? I have never tried to spark with it off. So would taking the bolt off make the magneto actually work? Cause it's still producing a charge with the bolt on, and of course I took the bolt OFF after the pic(stupid I know...) but my key is weird. Even when the rotor is parallel to the magneto arms, the key is at 12 o'clock. Just a bad make I suppose. But I have another prospect.

If I am getting a charge, from both the CDI continuity AND the magneto continuity(contrary to my prior belief), then could it be possible I may have put the piston rings on wrong? I mean I broke the original ones like an idiot, but ordered new ones and my brother helped me squeeze it in. Boy was that tough. Do you think maybe the piston rings are squeezing against the cylinder wall too much and that could be slowing me down that I won't get enough spark? I'm beginning to understand a LOT more as I scour these forums for help. (Which is awesome! :D)

Anyway, when I pedal the bike without the clutch on, it's fine and dandy. Definitely gonna' remove the chain tensioner and run no tensioner once I get the bike running. But I digress.

I have never EVER tried pedaling while the clutch was engaged, (that would be neigh impossible lol) but when I pedal normally about up to 5-7MPH, I dump the clutch, hold the acceleration to give it a little gas(before releasing clutch of course) and then after that the bike just slows down and you can hear the engine turn slowly. It sounds like something moving in slow-mo. The bike literally comes to a halt. Good way of braking if the engine doesn't work I guess. -_-"

I have no experience whatsoever with manual transmissions or 2 cycle engines. I own a 3.5L 6 Cylinder Dodge Charger, 07. I mainly do the repairs on it besides engine work(It's never NEEDED engine work. The car runs amazingly smooth.), so I don't really have too much knowledge on engines. Only turbos and sets like that. Forced air induction, not the engine itself unfortunately. So maybe the piston rings can be the culprit.

The main thing that I caught here is what livesteamfan said. Even though the spark plug is OFF the bike and attached to the cap of course...it's STILL no easier than when it is ON to push. That makes me believe the piston rings are squeezed in there barely. They are rubbing too hard against the cylinder wall, or maybe the clutch is too tight or something. (How can that be possible...?)

No matter what at the end of the day I have diagnosed that I am getting a charge at the end of the spark plug boot when the CDI is plugged into the magneto, and the spark plug still fails to spark. 3 Different spark plugs. One NGK B5HS and 2 regular crap ones from the factory.

If you guys would kindly look at the pictures I posted on the first page, you'll see just as 2door mentioned that I have one of the newer style magnetos. I don't know what a white wire is and I don't need to. There is only a blue and a black wire stemming from my magneto system.

P.S. The bike is getting gas, the carb is getting gas, running a 16:1 ratio with Royal Purple 2 Cycle oil and 93 octane gas, petcock gets unlocked, tickler button is triple checked, carb was tried multiple times at all choke points, no spark. Idler was changed to literally every thread count.

Current Status:
Magneto charge: OK
Magneto to CDI spark Cap charge: OK
CDI spark charge(From black ground to end of spark cap):OK
Spark plug spark: Non existant!

Maybe the engine piston isn't moving fast enough when the clutch is engaged to generate a spark. I know that it won't move fast enough when I do it by hand, lol. That's impossible to create by hand, it's too hard to move therefore it's too slow. I don't know how anyone else would be able to move that(as easily as in the video I posted) without herculean strength. It's the equivalent of trying to pull the wheel toward me with 1/2 my strength in one ARM. It's ridiculous.

Let me tell you. I've put some rough mechanical things together and performed some good maintenance on cars...and not once have I ever been stumped like this. Usually there's always an answer. Perhaps I am not giving enough information. If anyone needs ANYMORE INFO, please be short and concise about it. It tends to be easier to respond to multiple people if their responses are short as well.

I thank you all for your help, it's greatly appreciated. Where I come from I am used to no one knowing anything and I am usually forced to find answers by myself, for myself. So I thank you all for your patience and trying to help me get this bad boy on the road! ^_^
 
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crassius

Well-Known Member
Sep 30, 2012
4,032
158
63
USA
one takes the nut off only to check the position of the keyway when the piston is at the top - look at the pic in the thread on that subject

the motor turns easily with the clutch engaged WHEN YOU HAVE THE SPARK PLUG OUT OF THE MOTOR TO CHECK SPARK
 

zeroviral

New Member
Oct 20, 2013
21
0
0
Staten Island, NY
Words cannot express how angry I am right now. Found the problem:

while my brother was recklessly installing my new piston rings, he was assembling his engine also at the time. somehow his needle bearing got into my crankcase and was blocking the passage of it, making it difficult to turn.

popped it out and it fired right up, but of course the chain pops. on my way to fix it now.

also the engine was squealing and would die off after a few seconds...why is that?
 

FMB42

New Member
Sep 27, 2013
107
0
0
Idaho
Okay, how exactly are you "checking for spark" Z.V.?

It sounds like you might not be testing for spark correctly (which is why I suggested earlier that "just try to start it").

I sure hope that you're using a properly grounded and "known to be good" (or new) spark plug while you're testing for spark (with the plug out of the engine as crassius wisely mentions), rather than just pulling the plug wire off to see if the spark will "jump" from the cap to ground while you hold it some distance away from that same ground. Performing the old "spark jump test" with modern CDIs is not only dangerous to you, but is not recommended with certain CDI units due to the possibility that the unit will be damaged (I'm not sure if this will damage these kit CDIs tho).


Again, make sure that you have the kill switch temporarily disconnected and try starting it again with a brand new spark plug beginning with the choke in the "off" position (just in case the the engine is flooded) followed by increasing the choke a bit at time.

Anyway, be safe and hang in there...you get this sorted out!
 

zeroviral

New Member
Oct 20, 2013
21
0
0
Staten Island, NY
Okay, how exactly are you "checking for spark" Z.V.?

It sounds like you might not be testing for spark correctly (which is why I suggested earlier that "just try to start it").

I sure hope that you're using a properly grounded and "known to be good" (or new) spark plug while you're testing for spark (with the plug out of the engine as crassius wisely mentions), rather than just pulling the plug wire off to see if the spark will "jump" from the cap to ground while you hold it some distance away from that same ground. Performing the old "spark jump test" with modern CDIs is not only dangerous to you, but is not recommended with certain CDI units due to the possibility that the unit will be damaged (I'm not sure if this will damage these kit CDIs tho).





Again, make sure that you have the kill switch temporarily disconnected and try starting it again with a brand new spark plug beginning with the choke in the "off" position (just in case the the engine is flooded) followed by increasing the choke a bit at time.

Anyway, be safe and hang in there...you get this sorted out!

thanks, I got it fired up! a needle bearing was blocking the crankshaft from turning fully.
 

neum5464

New Member
Jun 13, 2013
25
0
0
Huntington Beach
More description on squealing would be better at getting a proper diagnosis but first thing is check the head bolts and gaskets for proper seal, I have heard anywhere from 10-12 ft/lbs is good on the aluminum head but I could be wrong. The chain you want to make sure the master link is facing the right way otherwise it will open when it passes over the motor-side sprocket. The other place a squeal might come from is the exhaust port if, again, the gasket is warped or the bolts are loose. I just built a China girl last month and the exhaust pipe from the kit was bent at the port and wouldn't connect flush to the motor. Just be careful to not over tighten the bolts as the china girl aluminum is not the best quality metal and may crack under too much torque.

hope you get the squeal fixed and riding soon
 

FMB42

New Member
Sep 27, 2013
107
0
0
Idaho
thanks, I got it fired up! a needle bearing was blocking the crankshaft from turning fully.
That's good news!

Meanwhile, can you please tell us more about this "needle bearing" and just how it was jamming the crankshaft? If this was a single needle roller from a "caged" connecting rod small-end needle bearing then you need to immediately find out if it's from your engine before you run it anymore (otherwise, serious engine damage could result if your small rod end bearing is missing a needle roller (posting some photos would be a huge help).

Here's a link that shows what these upper connecting rod small-end bearings look like:

http://www.pistonbikes.com/product-p/epcc28.htm

Each needle is about 1mm in diameter and 6mm long.
 

zeroviral

New Member
Oct 20, 2013
21
0
0
Staten Island, NY
That's good news!

Meanwhile, can you please tell us more about this "needle bearing" and just how it was jamming the crankshaft? If this was a single needle roller from a "caged" connecting rod small-end needle bearing then you need to immediately find out if it's from your engine before you run it anymore (otherwise, serious engine damage could result if your small rod end bearing is missing a needle roller (posting some photos would be a huge help).

Here's a link that shows what these upper connecting rod small-end bearings look like:

http://www.pistonbikes.com/product-p/epcc28.htm

Each needle is about 1mm in diameter and 6mm long.
yeah thank you! definitely heard of them coming loose but no, it wasn't mine. it was a double, it was my brothers which he stupidly somehow got into my crankcase. mine is on. the bearing got crushed and 7/9 of the pins fell into the engine, blocking the crank from turning and probably creating the squeal.(haven't checked, putting the engine back on now). I got all the pins out but I'm using my brothers motor now. I will update you all when I can. thank you for everything so far guys, you've been a library of useful info! :D
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Wow, some mess you have going here.

I take it you bought the 2013 Skyhawk 'box of parts' kit from gasbike?
If not then some of the below is not relevant.

Not the best choice for a complete rookie but that's OK, we'll fix you up.

First off the new 2013 magneto's don't have a white wire, it is a new coil winding and the ground connects with a bottom tab and grounded to where to where old white wire used to be.



All you had to do was mount it with the blue wire up.
Telling you to pull the nut of the shaft and dick with timing was really REALLY bad advice for a brand new motor, all you had to do was mount the Mag with the 4 bolts.

The CDI is mindless, 2 wires, but you have to remove the brass cap on the top of the spark plug!
If you broke your cap forcing over the brass nub no problem, the kit comes with a spare, just cut off like 1/4" from the end of spark plug wire and screw it in.

I have build over 50 2-stroke bikes with Skyhawk engines including 2 new ones with the 'parts in a box' as they are all I'll use and in all of those only one had an electrical fault, the ground tab from the mag wasn't soldered to the mount base well and a quick re-solder fixed that so it's not junk parts.

Undo whatever you did with the magnet and put it back tight the way it was from the factory.
Make sure your mag is mounted with the blue wire up and the same clearance all the way around the magnet.
Make sure you haven't broke the little U spring in your plug cap and take the plugs brass top off.
Then to make sure Ohm between the black wire on the mag to your head, it should be a dead short, if not you'll never get a spark because the head is the plugs ground.

That should fix your electrical issue as it really is simple.

You also mention you broke rings once, put in a new set and now your motor won't turn fairly free with no plug and the clutch out pedaling making the piston go up and down?

This is the main reason 'parts in a box' is not ideal for a rookie first build, you have to attach the piston and bearing to the crank arm and it has to be right.

There is an arrow on the top of the piston on the edge that points to the middle of the piston, actually what it pointing to is the front of the motor. Why they didn't put it on the other side of the piston pointing away from the center is beyond me but the arrow goes to the back side and points to the front (exhaust port).

There are 2 groves in the piston and they each have a little nubs that are located on the back side (intake) where the funky arrow is about 3 degrees to each side of it, one ring off to one side, the other ring off to the other side.

These nubs are where you line up the grooves in the rings to keep them in place and fill the slight void, if you forced the piston in and both rings notches were not split at the nubs they are pushing the ring out where the nub is.

In short if you can't pedal the bike around with the spark plug out pretty easy as the piston goes up and down you don't have the piston in right (assuming the rest of your drive train is good).

I'd start with the piston first and though this may sound like a condescending post to you it's more to all the people with no clue what 'Parts in a box' kit you have telling you try all kinds stupid unrelated stuff to try making matters worse.

I truly hope this gets you fixed up and others can learn something because getting a new 2013 YanDung factory engine delivered for $136 with the out of the box opportunity to check everything and do the top end right is really a great way all the way around to get around the EPA and get a nice engine kit, it's just not for rookies without proper tools like a torque wrench and metric tools to try first is all.
 

Kioshk

Active Member
Oct 21, 2012
1,152
10
38
Connecticut
Welcome ZeroViral. Let me be the first to say that I think you and your brother are a disaster-zone. How the HECK did HIS needle-bearing get into YOUR crank-case?!? Thanks for a great read, and PLEASE be sure to wear a helmet. In fact, wear two...like all the time, even off the bike. ;)

All kidding aside, you're WAAAY overthinking this project while at the same time you're being inundated with suggestions from too many people. I believe the adage "can't see the forest for the trees" is apropos. Try getting ONE engine running properly before you touch the other. Also, as was suggested earlier, put that multimeter AWAY; I believe you're not using it properly anyway. This can only lead you down the wrong path when trying to troubleshoot. If you MUST use it, stick only to checking continuity and resistance on the magneto-coil for now. ERASE whatever you think you know about the CDI except for blue-to-blue/black-to-black and cap-to-sparkplug out of your mind. I have no idea what you were trying to accomplish by cracking away the plastic from around that CDI's plug-wire, but from the looks of it now, I wouldn't trust using it. For your reference (and I'm hesitant to add to your already unwieldy pile of advice here) those spark-plug wires are screwed into the CDI and are further secured by some epoxy. You CAN however unscrew the wire using a pliers. You should ONLY be doing that if you're replacing the cable with an improved wire and cap...so FORGET WHAT I JUST TOLD YOU and focus on getting the crap that came with your kit working properly first, you can upgrade your kit later...MUCH later, after you understand the basics.
 

zeroviral

New Member
Oct 20, 2013
21
0
0
Staten Island, NY
great news everyone, its up and running! runs smoothly at 1/2 open choke.

thank you all so much, iyou don't know how much I appreciate it.

after getting all the pins out of the engine it turns over just fine. it apparently wasn't spinning fast enough to generate a spark as someone mentioned before.


thanks again everyone!! happy riding!!
 

fatdaddy

New Member
May 4, 2011
1,516
4
0
San Jose, Ca.
You Need a soldering iron to get started, again, harbor Freight probably has one cheap.
then cut off the connections and strip the wire back about 1/4 inch twist thm together as flat and smooth as possible, put a hot soldering iron on the wire then touch the solder to the wire.if it's hot enough it ill flow on th wire. Yer DONE, OH YEAH, Dont forget the heat shrink tubing. slide it over the wire FIRST. so you can slide it back down to the soldered connection.BLACK TO BLACK...BLUE TO BLUE
GLAD ya got it running bro, ya STILL need to solder those connections, and replace the stock plug and wire with a auto grade. I think I read yer using a NGK B6HS and thats great. ENJOY the ride bro. if ya gotta choke it to run right, Check for air leaks in the intake.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Like fatdaddy said, if you have to choke it to get it to run, you have other problems. The choke should be wide open after the engine starts. If you need to run 1/2 choke you have a major air (vacuum) leak somewhere in the induction circuit. Either where the carburetor attaches to the intake manifold or the intake manifold gasket where it attaches to the cylinder.

Tom