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I tried to browse a while to see if someone else had posted on the subject. My RC shut down at iddle and I could not get it to start. I tried checking the fuses and they were okay check almost everything before taking the bike to the shop. At the shop I watch the mechanic check current and fuses ans ended up at the CDI box. It seemed to be quite hot to the touch so he quickly pointed to that as the source of the problem. The thing is I went to 3 diferent Honda dealers and kept on hearing the same "these CDI's hardly fail" so I'm stuck with an issue here. Should I change lets say the relays or something first? The guy at the shop seemed very sure about the CDI but it is costly to buy a part and having another electrical issue burn the same part again and stuff you know what I mean. Anyway if anybody out there has had an issue like this any feedback would be appreciated.
 

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A hot CDI box doesn't mean it's failed. But if upon checking all the ignition connections there's a signal to the CDI but no spark (check both cylinders) then it could be the CDI.

I had mine fail when I first got the bike, on 3 different occasions. Eventually I traced it to the wiring harness having been modified by the previous owner to place the CDI in a different location to standard. He'd used crimp connectors, but this allowed a spark to occasionally travel between two connections and fried the CDI.

So I soldered and shrink wrapped each of (8 if I remember correctly?) the wires, then wrapped all together with insulating tape. Never had a problem again.

I have a brand new unused CDI I used to carry as a spare in case mine broke again, but knowing it's fixed for good, I could sell it to you if you need an SP2 one for what it cost me, which cost me less in Japan than what it'll be new in the U.S. now I expect.
 

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I tried to browse a while to see if someone else had posted on the subject. My RC shut down at iddle and I could not get it to start. I tried checking the fuses and they were okay check almost everything before taking the bike to the shop. At the shop I watch the mechanic check current and fuses ans ended up at the CDI box. It seemed to be quite hot to the touch so he quickly pointed to that as the source of the problem. The thing is I went to 3 diferent Honda dealers and kept on hearing the same "these CDI's hardly fail" so I'm stuck with an issue here. Should I change lets say the relays or something first? The guy at the shop seemed very sure about the CDI but it is costly to buy a part and having another electrical issue burn the same part again and stuff you know what I mean. Anyway if anybody out there has had an issue like this any feedback would be appreciated.
You need a peak voltage tester or a scope. You should have 12 volts, ground, two 5volt signals and two minimum 100 volt outputs to the coil. Dont guess, test. Mine went bad only having 20 volt output. They are expensive if you can find them. I used two atv cdi boxes to replace the one costing me about 30 dolars
 
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