CDI Failure(s) ?

[saetta]

My first bike, 49cc, over one year and approx 1100 miles on this motor, and my CDI no longer produces spark. With a multi meter my magneto tested OK. Existing wiring and connections are good. I replaced my magneto just to be pro active recently and it test OK. After replacing my CDI the spark is back. However on my second day of riding, my engine quits and again will not produce a spark. And per my meter I have no voltage to the spark plug contact of the new CDI while manually cranking my motor with the spark plug removed. Anyone else have a CDI fail so quick?

 

["the prussian" Shop Dogs]

have you changed the cheap chinanees wire with a new american(japanesse) one
just find a plug or coil wire with the same size insulation cut of the factory end's ,uncrew the old in w/ the new .I also change the plug cap for silacone rubber one (even if they do dry roit over time there two bucks) worked for me after i ordered a new cdi (oh well) hope this helps.

 

[saetta]

Good call. Yes I changed the plug wire early on when I built the bike. When I tested both CDI,s I first remove the plug wire and touched the multi meters contact directly to the screw on the CDI where the plug wire would mount. On this test i am showing zero output of voltage when I crank the motor over.

 

[xlite]

My first bike, 49cc, over one year and approx 1100 miles on this motor, and my CDI no longer produces spark. With a multi meter my magneto tested OK. Existing wiring and connections are good. I replaced my magneto just to be pro active recently and it test OK. After replacing my CDI the spark is back. However on my second day of riding, my engine quits and again will not produce a spark. And per my meter I have no voltage to the spark plug contact of the new CDI while manually cranking my motor with the spark plug removed. Anyone else have a CDI fail so quick?

I've had one CDI quit and half dozen magnetos. A bike buddy if mine has a magneto he calls "CDI Killer". He swears it blows CDIs. I said "no way" and he offered to let me try it but I declined.

Like Norman mentioned in another thread today, running with the plug wire not connected can do in a CDI. Not always but with nowhere for the high voltge to go you are asking for trouble.