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Discussion Starter #1
Ok I currently have gotten a 1991 honda trx250x I have replaced the ignition coil, stator, pickup coil and cdi. I currently still have no spark. I have seen a lot about people saying disconnect the reverse switch and make a jumper from the grey to gray/black at the front of the frame along with the rest of the wires but I am unable to actually locate the reverse switch itself. It is said to be under neith of the brake pedal but I can not find it. I personally do not know what this switch looks like but I have looked all over for any type of gray wire around that area and found nothing. Any help to finding my no spark problem or the reverse switch problem would be greatly appreciated thank u
 

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Discussion Starter #2
Also if anyone knows how to bypass the kill switch that would be helpful to eliminate that as a possibility
 

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To bypass the kill switches simply disconnect the black wire with the white stripe coming out of the CDI box.

The ignition system is very simple - the black/red wire from the alternator provides AC voltage to the CDI box -the blue/yellow wire from the pulse generator triggers the CDI to fire the coil - the black/yellow wire carries the voltage from the CDI unit to the coil - the gray wire goes to the reverse switch to limit the engine RPM when in reverse - the green/white wire at the CDI box is ground.

The most overlooked part of the ignition system is the AC regulator - if the regulator goes bad, you can lose spark - only two tests for the AC regulator (other than replacement with a known good unit) is to unplug it to see if you get spark and if no spark, leave it unplugged and ground the green wire side of the coil to see if you get spark - if you get spark either way, replace the regulator.

Other than that, checking connections will usually find the problem - when I say checking connections, with the black/white wire unplugged, you have to check continuity of each wire from end to end and if the connectors are making connection within the multi-pin plugs.
 

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Discussion Starter #4
Ok thanks for the advice. I will try that all in the morning, when u say the alternator is that the stator? Or is it something else?
 

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The stator is the winding part of the alternator and the alternator is both the stator and the flywheel together. To be precise, the stator is the winding, the flywheel is the rotor and the two parts together are the alternator, but in the world of mechanics, regardless of the term used we know that one is useless without the other, so....... They are considered the same thing until we separate them. The output of the stator is the same as the output of the alternator. The only thing the rotor does is carry the magnets that cause the stator to generate an output and the pulse generator to generate a spike of voltage.

The reverse switch is on the clutch cover just in front of the reverse lockout operator.

Question; where did you get the new CDI? Are you sure it is an AC activated unit and not a DC unit?
 

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Discussion Starter #7
Thanks for ur help, that all makes more sense now. And the cdi was switched from another matching quad that runs
 

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Discussion Starter #8
I tried another stator and pickup coil to see if others were bad, no spark. Bypassed ignition switch no spark. Ur saying that if I just completely unplug that regulator and then kick it over if I get spark it's bad?
 

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Discussion Starter #9
Replaced the ac regulator with another one from another running matching quad, any other ideas would be appreciated
 

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Nope - now you are down to flywheel timing, magnet strength, good vs defective parts and wiring connections.

One time I had to make my own wiring harness eliminating all unnecessary connections - got spark and then chased down the bad wire by swapping connections one at a time - it required removing the terminal pins from the multi-pin plugs so wires could be replaced one at a time - PITA, but I got it fixed.

One time I had a bad flywheel on a Yamaha Warrior, but that's one bad flywheel in 40 years of working on these things.
 

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Discussion Starter #11
Ok. I think I can get the flywheel from another running quad and replace that. Is there a way to know if the magnets are good on these? Arent the magnets on these specific quads just small little circle magnets on the front of the flywheel?
 

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No way to check the magnets unless you have access to a Gauss meter (measures the strength of a magnetic field) - even then, you have to have specifications (not published by Honda) or a known good flywheel to check against.

The magnets are more than a 'small circle of magnets on the front of the flywheel' - there is typically a minimum of 4 and perhaps as many as 6 very strong permanent magnets glued to the inside of the flywheel - sometimes visible and sometimes covered by a thin piece of metal. Best test is off a running machine - changing flywheels gives you the opportunity to check the condition of the flywheel key - NOTE: the flywheel key is for alignment, NOT TO HOLD the flywheel - the flywheel is held by being drawn up on the taper of the crankshaft - it is important to get the flywheel tight. I use a 1/2" air impact to tighten flywheels.
 
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