Re: spak plug head comes loose
All spark plugs come with a threaded tip and cap on the top end. The kit plugs come with the cap removed so you can use them with that piece of junk boot that they give you. The very first thing you should do when you get your kit is throw that plug boot in the trash and replace it with an automotive quality boot. That will require that a new plug be used, one with the cap still installed.
Almost without exception any wire you get from an auto parts store today will be resistance wire. It will not have a metal conductor so be careful when you install the new boot to make sure you have good electrical contact with the conductive core of the wire. You'll also need to use the same care when screwing it into the CDI wire post.
You'll be better off if you can fine copper, or at least a metallic core spark plug wire instead of resistance wire. Motorcycle shops, lawn mower repair shops and some auto parts stores still carry metallic core wire.
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