anyone how to change the spark plug cable on the little cdi box???

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
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Duvall, WA PNW
www.sickbikeparts.com
anyone how to change the spark plug cable on the little cdi box??? please post pics



.bld.
Sorry, no pics. From our site:

Spark Plug Wire
Remove your old spark plug wire from the CDI box by unscrewing it in a
counterclockwise rotation. Test fit the plug wire and cut it to an appropriate length. Screw
the cut end of the plug wire into the CDI box using a clockwise rotation and apply firm
pressure toward the CDI at the same time. The plug boot will require a standard ball type
end on you plug. The old stock one had this piece removed exposing a threaded tip. This
boot will not work with the stock plug. Be sure to acquire the correct plug.
http://sickbikeparts.com/Manuals/Installation%20instruction%20for%20assorted%20products.pdf
 

Goat Herder

Gutter Rider
Apr 28, 2008
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Resistance kills spark Don not use a car plug wire that has resistance. They were used on cars to get the humming sound out of the radios. I used the mega cable from a trunk mount car amp it fit perfectly. Yeah overkill I know , works great never been shocked , But I don not go out my way to touch it either.
 
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jasonh

New Member
Jun 23, 2008
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right now I am using a piece of good coax cable I had laying around. Has a solid copper core, and screws onto the cdi just dandy.
 

Goat Herder

Gutter Rider
Apr 28, 2008
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N.M.
The thicker cable like for car bass amps works good . I had some scrap laying around try ed it left it that way.
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
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www.sickbikeparts.com
The trick is to fine the best wire for performance, that does not cause interference with the speedo (or pacemaker), flexes and lasts, and has good insulation so you don't get the liven bejeezzus zapped out of you. We settled on making our own wires from Magnecor wire.
 

donuts31

New Member
Nov 9, 2008
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Colorado
There is nothing wrong with the stock wire. Its pure copper and has very little resistance. Why the rush to replace it? If it isn't broke, don't fix it for some perceived improvement that doesn't realize with replacement.
 

thatsdax

Member
Feb 22, 2008
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I agree.. The Stock is Copper and is by far the best for spark. But copper wire or pure wire is the worst for RF interference. A lot of folks talk about this mm and that mm, larger mm , and such for a wire set. But.. Keep in mind this.. They are not Wire typically. They are carbon and offer low RF "radio Interference", and the larger the better. This is true for for wire as well. R x l/a is the empirical formula for Resistance...... "a" being the cross section of the single wire. Keep in mine the skin effect. At any rate. Larger is better. And Copper is better than Carbon for spark and these kits come with copper wire , which is best for a hot or hotter spark. Most of the 2 stroke kits come with a 250 ohm magneto. The better engines or better magnetos are 357 ohms and produce a hotter spark. So.. If you want the hottest spark, stick to stock copper wire set and get the hotter mag. Thanks.. Enjoy the ride...
 

jasonh

New Member
Jun 23, 2008
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I agree.. The Stock is Copper and is by far the best for spark. But copper wire or pure wire is the worst for RF interference. A lot of folks talk about this mm and that mm, larger mm , and such for a wire set. But.. Keep in mind this.. They are not Wire typically. They are carbon and offer low RF "radio Interference", and the larger the better. This is true for for wire as well. R x l/a is the empirical formula for Resistance...... "a" being the cross section of the single wire. Keep in mine the skin effect. At any rate. Larger is better. And Copper is better than Carbon for spark and these kits come with copper wire , which is best for a hot or hotter spark. Most of the 2 stroke kits come with a 250 ohm magneto. The better engines or better magnetos are 357 ohms and produce a hotter spark. So.. If you want the hottest spark, stick to stock copper wire set and get the hotter mag. Thanks.. Enjoy the ride...
For the best spark, you want the lowest resistance possible in the wire.

But I hope what you're saying about going with the higher resistance magneto is that they have a higher resistance due to more winds and thus higher voltage. Do you know how many volts the different mags put out of the blue wire at idle? I think I get around 60v on mine. I haven't checked the resistance to see what it is.
 

hilifestile

New Member
Dec 16, 2008
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weston,florida
guys i just install a new 7mm spark plug cable for cars and work perfect if not better...i ride mi bike this morning and is a smooth ride!!! still using original spark plug and original spark boot ....
 

jasonh

New Member
Jun 23, 2008
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The stock wire and boot gets very hard and brittle if it gets really cold. We had a few days of temps around 0 degrees and the garage isn't heated. Stepped on the wire accidentally and the boot shattered. Good thing I wasn't using it.
 

Dave31

Active Member
Mar 1, 2008
11,204
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Aztlán, Arizona
There is nothing wrong with the stock wire. Its pure copper and has very little resistance. Why the rush to replace it? If it isn't broke, don't fix it for some perceived improvement that doesn't realize with replacement.
I used my stock wire and plug for fives years and a little over 4,000 miles...I had no problems. I changed them out hoping I could get a little better performace...did not change a thing, runs the same.
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
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up north now
I guess it depends on what you get to start with. Most people change the stock wire and plug (me included) at the same time and get better performance.

Could be the plug?
Could be my imagination.