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  #1  
Old 07-18-2016, 11:22 AM
Jim C Jim C is offline
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Default plug wire

I have been putting together a 29 inch cruiser for a long time. This has been a very frustrating build and I have lost interest several times. I started this build using a 49 cc 4 stroke motor and got it running but decided to go with a 66 cc 2 stroke and that is what I am working with now.
The motor is installed and about ready to go. When I mounted the ignition block the insides of the spark plug cap fell out on the floor. My attempts to reassemble it failed so I bought a new ignition block and installed it today. I put it on the bike and checked it for spark and it did work. When I pulled the spark plug of of the cap the insides fell out and onto the floor. I am willing to buy a new ignition/coil but really want a better quality unit than the ones that seem to fall apart. Who sells a good product or how can I fix the caps I already have?
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Old 07-18-2016, 11:38 AM
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Kioshk Kioshk is offline
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Default Re: plug wire

The CDI (the black block) should be fine...these are basically indestructible. The rest of the ignition hardware STINKS. Replace the wire and cap with a decent quality automotive assembly. The wire leading into the block is actually screwed in there, and kept from loosening with glue. You can simply unscrew the wire from the block (lefty-loosey) and screw in your new and cut-to-proper-length ignition wire...no glue necessary.
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Old 07-18-2016, 02:15 PM
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2door 2door is offline
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Default Re: plug wire

In addition to the above advice you need to know that where the wire goes into the CDI there is a small threaded protrusion that looks like a sheetmetal screw poking up from the inside. While you're digging the glue out to remove the wire be very careful and do not damage that screw.

As for the wire, I see ne need to replace it. The ignition wire that comes in the kits is a metallic conductor wire that is superior to most of what you'll get from an auto parts store today. They sell resistance wire and the higher the resistance the less current to the plug. If you decide to use resistance wire you should know that there is no metal conductor to thread onto the screw in the CDI. You'll need to find the exact center of the wire as you thread it in.

The spark plug boot that is in most kits is the weakest link. It should be replaced with one made to snap onto the top of a spark plug as opposed to that silly spring thing that is supposed to hold onto the threads on the top of the kit plug. Ask for a spark plug boot at the parts store. They come in straight design, or angled. One with a 90 degree design works well.

Good luck.
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Old 07-18-2016, 03:57 PM
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Cylon Cylon is offline
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Default Re: plug wire

http://www.ebay.com/itm/NGK-Spark-Pl...4AAOSwgApXCtyG

Problem solved.

If that doesn't work replace the magneto.
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Old 07-18-2016, 04:23 PM
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Default Re: plug wire

BTW it helps to have complete cdis like that which come with the kit on a back up all the time I try to keep a few around as I help others fix there bikes in my area. Some of them work great and some are duds. I doubt they have much QA for the kits.
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Old 07-18-2016, 05:55 PM
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Default Re: plug wire

Check this as well if you ruined your magneto.

http://www.ebay.com/itm/281852483284...%3AMEBIDX%3AIT
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Old 07-18-2016, 07:01 PM
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2door 2door is offline
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Default Re: plug wire

In ten years of building and riding I've only had one CDI fail. I maintain that most of the ignition problems seen are the result of that plastic spark plug boot which both of those links show as part of their system.

GET RID OF THEM and use a boot made for automotive use. Those heavy plastic kit supplied boots are JUNK!

Tom
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Old 07-19-2016, 04:39 PM
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Dave31 Dave31 is offline
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Default Re: plug wire

Same 10+ years here, never had a CDI go bad. Mags yes, never a CDI for me?
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  #9  
Old 07-19-2016, 11:03 PM
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maniac57 maniac57 is offline
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Default Re: plug wire

Never had a CDI box fail yet.
DOZENS of coils, but never a box.
I went to the Screaming Roo CDI/HD coil combo and have not had to touch it in about 2 years
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  #10  
Old 07-23-2016, 01:05 PM
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bairdco bairdco is offline
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Default Re: plug wire

I had one cdi fail. After two years it just didn't spark anymore. You old timers know me, so no, it wasn't bad connections, crappy solder, etc. Just quit working.

I always changed the plug wire to a 7mm copper core wire, new boots and terminals. All the bikes I built, the stock wire went straight into the trash.
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