I need a little diagnosis help. Picked this machine up not running. The stator cover was removed and it was weather beaten from sitting for 2 years. I cleaned the carb, put a fresh battery in it and reinstalled the stator...no spark. Cleaned the switches tested the stator and ohmed the coil. The coil tested bad turned out the wire was broken inside. New coil...no spark. I couldn't find good info on testing the stator for this machine. In the past I have ohm tested the stators on other machines but online chatter says voltage test this one. I did ohm test it first and on the Bl/W wire and Y/W which I believe are the CDI trigger wires I got 120ohms. When I voltage tested it I got 5.5 volts AC on the white wire (charge circuit) and .5 volts AC on the two trigger wires. That seemed very low so I ordered a new stator and it read absolutely identical on the ohms and volts when tested...no spark. Any ideas what to test or how to test?

 

0.5v on a trigger coil is fairly standard. 5.5v on the power coil seems a bit low though, they are often over 50v, but I'm not sure what the Honda 90 should be. See what voltage you get with the new stator. Your wiring colour description doesn't sound right. I only have the pre 2005 Manual (no battery on them) but it gives exciter (ignition power) coil as black/red wire and 400 to 800 ohms resistance to earth, trigger (pulse) coil blue/yellow to earth 50 to 200 ohms. Check that black/white kill wire is not earthed with ignition on and that the earth wire to CDI is earthed. Then "if everything tests right but you don't get a spark, it has to be the CDI."

 

I put a new stator in and it measures the same in ohms and volts. The pulse trigger has two wires one blue/yellow and one yellow white and they ohm at 120 and produce .5 volts each.

 

Right, they have gone over to DC CDI for the 2006 model. Black/white will be pos feed from ignition switch to CDI to power the spark, two wire trigger coil is unusual for Honda, and pink is a conundrum, unless it is the rev limiter, which only works in top gear (I think) so would need to be connected to the gear position switch. White wire is the alternator to charge the battery, so not part of the ignition circuit.

 

Yes, the pink is the 4th gear rev limiter. If I have 12v at the CDI, and trigger signal from the two wires then it has to be the CDI is bad. I have a new coil on it that ohms out perfectly.

 

Yes, do check the CDI earth, as a bad earth will kill the CDI and the new one, if you fit it without fixing the earth.

 

Thanks for mentioning the ground. I had not tested it leaning toward signal input and power. I just tested the ground at the coil and CDI and it is an open circuit. So I have to trace it down.

 

I want to close this one out with a FIXED report. Sure enough it was just the ground. On the 06-21 TRX 90 they have a separate ground wire for the coil in the harness attached to the frame beside the CDI. The ground was not making sufficient contact. Cleaned it up and for good measure ran a extra ground wire from that location to the main ground wire at the starter mounting bolts.