Troble shooting bicycle engine cdi and spark plug wire

deacon

minor bike philosopher
Jan 15, 2008
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Okay I took the bike's electrical parts off to shoot the frame with a little color. I rewired the kill switch and replaced the parts in doing so the spark plug wire came lose from what must be the coil. (the black box on the frame) Now the bike wont even try to start. It has gas and it was choke ten ways. I had the kill switch on off and disconnected. Nothing seems to help..

I'm thinking the spark plug wire did not have a connection when I shoved it back in. I guess I need a new one. so here are the questions.

If you agree that I probably need one, what should I get. Is there something better for this application than anything else or do I just take the old one in and ask for a similier one.

Also on most sparkplug wires I have seen, there is a metal tip on the distributor side of the wire. Is this supposed to have one, If so it is still in the coil and I have pulled the wire out of it. Which would also explain my problem.

Advice please....
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
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Re: Trouble shooting specific questions

Deacon - what do you see down in the hole in the CD spark module? (aka coil) is there a wire or contact? If so - Seems like a good time to get a good automotive wire and boot with a standard contact....but depending on what is in the hole, that's the catch....
 
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deacon

minor bike philosopher
Jan 15, 2008
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north carolina
Re: Troble shooting specific questions

I forced the wire back in and twisted it and it runs now. What is down in there looks like a pin sticking up that slides into the center of spark wire. I'm not sure if it is the end of the wire that came off or if that is the way it supposed to connect. Either way it is working now, so I just taped it in place it will probably hold a while but still I'm curious what the connection should look like.

Thanks for the interest...
 

paul

Well-Known Member
Dec 23, 2007
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Re: Troble shooting specific questions

the little black box or cdi has a screw in it which is where you get you contact. the plug wire is screwd onto that. the wire dosn't screw in easy at least it didnt with mine. after you get it screwed in give a light pull if the wire comes out it did not scew in enough. what you can do is take a small screw and thread it in the wire and take the screw out then screw into the cdi. makes it a lot easier that way
 

deacon

minor bike philosopher
Jan 15, 2008
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Re: Troble shooting specific questions

Should move this to tips taken and left thread. It is a good tip to know. This is the kind of thing I could never get the last place I tried to get information. The tip about the screw and cutting a little off to make new threads will be life saver if it happens on the road. You just can't know too much when you deal with this kind of thing.
 

paul

Well-Known Member
Dec 23, 2007
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Re: Troble shooting specific questions

to add to this. if you replace your wire and boot you will need to get a little screw on tip for the spark plug which comes with the plugs when you buy them, the cheap boot that comes with the kit clips over the screw on the spark plug
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
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Re: Troble shooting specific questions

to add to this. if you replace your wire and boot you will need to get a little screw on tip for the spark plug which comes with the plugs when you buy them, the cheap boot that comes with the kit clips over the screw on the spark plug
That my fine motorized biking fiend, is why I want a new wire!:ride:
 

deacon

minor bike philosopher
Jan 15, 2008
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Re: Troble shooting cdi and spark plug wire

It's amazing how much information is available when people get into the joy of sharing. Reminds me of the old teaching model.... see one... do one... teach one....
 

Andyinchville1

Manufacturer/Dealer
Dec 26, 2007
502
1
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Scottsville, VA
Re: Troble shooting cdi and spark plug wire

FWIW - Some people (after screwing the new plug wire onto the little metal "stud"), take some high strength tape and secure the wire to the plastic case iteself....Then you can take some RTV sealant and use it over the taped joint to waterproof / weatherproof the connection.....this helps to make sure the wire is physically secured to the CDI box itself and that water/moisture won't be able to cause problems in the future.....probably very important if you use your bike for daily transportation.
Andrew
 

MotorbikeMike

Dealer
Dec 29, 2007
477
1
18
Sacramento
Re: Troble shooting cdi and spark plug wire

Spark plug wires? I make my own for the antique side, cloth covered, copper wire I crimp on an end, and screw a little brass knurled not on it.

Different strokes?

Mike
 

paul

Well-Known Member
Dec 23, 2007
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attaching plug wire to cdi

i took a picture of the plug wire cap that came with the kit. wire attachment is the same way for cdi and cap that come with the kit. a good cap does not have the screw in it. inside the housing is a screw. you must screw the wire into the cdi. some times it is difficult to get started. i found first take a screw lying around the bench use to get a hole started in your plug wire. the picture is not that great but as you can see it is a good sized screw and it also serves by expanding the wire to help make things more waterproof. some people also expose a little wire before screwing in.
 

Attachments

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
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Re: Troble shooting cdi and spark plug wire

some pictures of how to wire the cdi and kill switch.
First picture is a single wire kill switch, the white wire is to lights or capped off. The kill wire is attached to your colored wire or blue wire off the coil as I understand the black wire is a ground wire.
Second picture is 2 wire kill switch set up.



 

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
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Spark plugs

Pictures of my stock sparkplugs and how I modify them to make it run faster and jump higher. I seem to not be able to get a sharp clear pic.of the modified plug. beleive it or not but I cleaned plug and gaped it cleaned the threads and a very small dab of never seize on the threads, center electrode was a nice chocolate brown. I've got more of the same plug but they suck as well.





 

paul

Well-Known Member
Dec 23, 2007
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Kalamazoo, MI
Re: Trouble shooting cdi and spark plug wire

Norman the use of that board was a stroke of genius to explain and show us stuff. good job! i am going to have to try that with my spark plug. i have never seen that modification before
 

Andyinchville1

Manufacturer/Dealer
Dec 26, 2007
502
1
18
Scottsville, VA
Re: Troble shooting cdi and spark plug wire

Interesting mod Norman!.....I have never seen that before....do you feel performance is
enhanced over a standard plug chop?...

Thanks!

Andrew
 

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
2,605
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68
pampa texas
Re: Troble shooting cdi and spark plug wire

Interesting mod Norman!.....I have never seen that before....do you feel performance is
enhanced over a standard plug chop?...

Thanks!

Andrew
Andy
A old boy in Mo. that races chainsaws of all things told me about this and also get this he would knock off all the fins on the flywheel and remove the base gasket. He said the hotter the better and removing the base gasket advanced the port timing and bumped up the compression to seal it you use the anarobic gasket sealer as a gasket. I tried the base gasket thing on a 43cc scooter along with a home made advance key on the flywheel I left the fins on couldn't bring myself to knock those off I also matched all of the ports and cleaned up the inside so slick a fly landing on it would skid off and break its neck.. Every 1 percent emprovement you can do will add up and make a eventual fire breather. Or poorboy rodding
some food for thought
I'm sorry I didn't answer your question does it help over a standard plug chop? Whats that?
If you will notice these are factory china plugs and I've yet to buy a replacement plug. I'm a cheap skate.
You can do the mod to any plug you use if you want.
Norm
 
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deacon

minor bike philosopher
Jan 15, 2008
8,117
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0
north carolina
Re: Troble shooting cdi and spark plug wire

You guys are speeding up the bikes and I'm slowing mine down. there is something wrong here.
 

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
2,605
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38
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pampa texas
Re: Troble shooting cdi and spark plug wire

The idea behind the cutting of the ground electrode is to uncover the center electrode so the flame kernel will propagate quicker and start the burning of the fuel quicker and better for increased performance same thing as the snake oil spark plugs you pay out the rear for. Split fire to name one that comes to mind. I attended a school last year on industrial engines and ignitions in general and the latest wave and hottest item coming out is a spark plug that fires a sonic shock wave that fires the fuel off in the cylinder I viewed a very high speed film of this and looks like we will be seeing this in the near future looks like a cannon going off really looked neat. the thing promotes a cleaner burn and more power so there is a performance gain as these people use dyno's and all kinds of wild equipment to evaluate the thing.
Norman