ZOT maker

[Howardgf]

Hi all. While I am researching all things HT80, and greasing my Huffy bearings, does anyone have a good understanding of how our CDI triggers work? They look(ARE) very simple to build, but no one seems to have one they are ecstatic over. What part, and value thereof, does what, and how, or why? I'm not up to figuring this out yet, any Gurus here care to enlighten? Thanks, H.

 

[2door]

There is a lot of discussion here on the Chinese 2 stroke ignition system. If you're interested in building your own here is an old thread that has some good tech info.
http://motorbicycling.com/showthread.php?t=28439

You can also use the 'Search' and type in 'CDI'. You'll have plenty to read on the subject.

Tom

 

[Howardgf]

Thanks Tom. Reading furiously, but was hoping that, somewhere along the line, the CDI advance/retard thing had been nailed down. Still researching all things HT 80. H.

 

[Agreen]

The R/C network that makes up the gate cicuit for the SCR (in the CDI) is what controls timing retard. Unfortunately, you can't advance it with electronic circuits. That can only be done by moving the magnet or pickup. Now, as for how much advance or retard it needs, is all up to the individual engine. Each one is made different. So what works on one will not on another. What that means is that people have experimented with different CDIs and have found that one with an adjustable gate circuit is the "best for all".

I will say that I have never seen anyone say that the timing needed to be advanced any. It's always needed to be retarded some. So by adjusting the R/C timing of the SCR's firing gate, you can retard the timing to your own value as necessary.

 

[Howardgf]

Got it. Thanks. Think I'll see if it runs first as is. H.