What's inside CDI 80cc

Greg58

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I don't remember the values of the capacitor or which diodes and resistors I used, it also has a SCR, It ran good on top end but with no advance it wasn't good for low end.
 

Greg58

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I had a lot on a previous tablet that crashed, the basic diagram is below.
 

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Kehkou

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I believe the higher end ones retard the spark at higher RPMs, effectively removing the 'rev-limit' of stock CDI.
 

Urban Fatbiker

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I believe the higher end ones retard the spark at higher RPMs, effectively removing the 'rev-limit' of stock CDI.
Yes this. Most of them seem to simulate a stepped curve retard. I think HD Lighting and BBR Stage 1/2 are similiar.

Its too much advance at high RPM that makes it vibrate bad at top end, probably worse for 48CC. Think weedeater CDI, it ain't much better.

Per MHO and a butt dyno comparison of a 'hi-performance' CDI versus a BBR stage 1.
To me, a huge difference. No wonder the small engines blow apart in a few hundred miles.
 

ixxGunnerxx

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cool thanks for the Replies , so its just a bigger wire and Bigger Capacitor....
Its just Funny how They Sell "high-Performance CDI " on eBay ..
but yet there is No way of Telling if and What it is until you buy it and Test it ..
 
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