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Discussion Starter #1
Got a electrical problem that's beyond my skill level. Got a 98 trx300fw that I had Givin to me with a bad CDI BOX. Bought a new OEM box and started the bike. Within seconds it shorted the box out. Expensive couple of seconds. Any thoughts on what problem I might have and if it's even worth messing with.
 

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I'm thinking a bad voltage regulator / rectifier might have fried your new CDI.

Rick

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first question I would ask , is the CDI box you put in off e-bay or an OEM CDI from Honda , e-bay's china junk is hit or miss and mostly misses ---------- second question is what year did you order for , 98-2000 300 2wd and 4wd are the only atv's that cdi will work on
 

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JD , that sucks , Ricks has been good for me , but I am running it on a 95 -------- ya know I thought I had read where Rick's didn't make anything for the 98-2000 , just went to their site and they show a 98 300 cdi , but mention 350 in the description , SamUK , I think knows about the latest model 300 and the Rick's cdi
 

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Ok..Well finally got in touch with the man that gave me the atv. He said the last cdi that was on the bike had done the same thing. He started it and the box shorted out. Said only thing he had done prior was had the starter rebuilt. Turns out it's blown 4 cdi boxes now.
 

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Ouch! Get a copy of the FSM if you haven't yet, there are wiring diagrams in the back... I imagine the wiring has been altered or something is hooked up backwards? I suppose the regulator/rectifier could be shorted too, allowing raw AC voltage into the CDI. Run some tests on the stator windings and regulator to look for shorting and look for bare wires rubbing on the frame. If the wiring diagram shows any diodes are in the electrical system, check those too.

The FSM is HERE.

I would start at the battery & solenoid and go through the entire harness looking for problems. Put eyeballs on the ignition switch harness to make sure someone hasn't swapped in the wrong switch or cobbled on it. Put the same eyeballs on the kill switch harness plug. Check for missing diodes etc.
 

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Ok.. I''ll check it all out. Looked over most of the harness already and it hasn't been hacked on. Didn't find any bare wires either. Will tear into the switches and stuff when I get more time. Thank yall for the help.
 

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JD , that sucks , Ricks has been good for me , but I am running it on a 95 -------- ya know I thought I had read where Rick's didn't make anything for the 98-2000 , just went to their site and they show a 98 300 cdi , but mention 350 in the description , SamUK , I think knows about the latest model 300 and the Rick's cdi
Well...... That knocks mine out, fish if you might could find that article , I'd like t read it, @SamUK (i believe) has a ricks on his 300, but, lol i don't recall what year model 300 he has...wander what troubles one would run into changing to an older stile cdi pigtail ? And which to change , the bikes PT or the CDI's ?
 

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Check the frame ground for the wiring harness too. There is a diode that protects the CDI:



Let us know how it goes...
 

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Ok, so Ricks don't make a hot shot series cdi for 98-00 models, it's just a stock cdi. You have to change the wiring loom/harness for an earlier type and then buy the cdi to suit, or chop off the 98 plugs and solder in an earlier plug.

The splicing can be done, all the wires are there and are the same, I haven't actually wired mine as yet, when I do I'll put it in a thread for future reference.
 
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