TRX 350fw no spark

[Bobbles]

New to the forum here, hoping someone can help. I have replaced the cdi, coil and sparkplug yet still no spark. The measurements for the igniter and stator are what they are supposed to be, the kill switch is working as it should, the neutral light is working as well. Any ideas where else to look before i start trying to pull it apart for the stator and igniter? 

[Mech]

Have you checked the wires ?

Are you sure the power and the signal are both getting from the stator to the cdi unit ?

Are you sure the kill switch isn't either shorted or open circuit because of a chafed or broken wire ?

You should check the stator and trigger winding resistances right at the cdi, that checks the wires are all intact. Then you should use an analogue volt gauge at the cdi to check there is actually power coming out of the stator. The cdi charge should have an AC voltage and the trigger should put out one brief pulse/wave per rev. A digital gauge is quite likely to miss the trigger pulse.

[Gwbarm]

👍

[Bobbles]

The kill switch is defiantly working, checked at the wire end for open and closed. Does the stator not go through the rectifier before the cdi? I will have a go at measuring it at the cdi end. I have measured at the coil in, it is impossible with an analog meter, but the output dc looked high, what should the output dc to the coil be? I have hard wired most of the joins by the cdi area as some of them had corroded, I thought I'd found the issue in one of the wires, but that would be too easy. Thanks for your help

[Mech]

I'd need to look in a manual to be sure, but it's likely that the stator has three wires coming out for the battery charging, and they do go through the regulator, and it also some other wires that go straight to the cdi unit.

If it's as I say then two wires are for charging the capacitor in the cdi, and two that are  to trigger the cdi to discharge the capacitor through the coil to produce the spark. The wire to the coil only has power in it for a millisecond as the capacitor discharges, and when it discharges it will be hundreds of volts and a huge current.. so be careful.

I'd need to know the year to find the right manual though.

[Bobbles]

I think it's a 1989

[Mech]

I think this is the one you need. Compare the ignition circuit diagrams in the ignition section, with the bike to be sure..

[Bobbles]

Thanks, I just need to get to ten posts to download it 🙃

[Mech]

Nearly there... 

[Bobbles]

So it looks as though I might need to get a dc cdi, I think the one I purchased was an ac as it's a bit smaller. I will get a dc one and see if that works

[Mech]

Did your wiring colours and the plug shapes match any of those wiring diagrams Bobbles ?

Have you identified which model it is absolutely ?

have you checked the output from the stator is getting to the cdi?

Trying parts can be expensive, and frustrating !

Edited November 24, 2024 by Mech

[Bobbles]

The wiring is the foreman with the dc cdi. I'll check the stator signal to the cdi this weekend, but i will have to troubleshoot the starter button first, hopefully I just unplugged something... It's not the starter though as bridging the solenoid works. 

[Mech]

Some will start if they are in gear, (or think they are in gear) if you put the brakes on. It can be a good work around for faulty neutral switches..

Ok, so if you are sure about the wiring, the book should explain how to test it all.. I think it even had resistance readings for the cdi unit..

[briantutt]

I have these same issues, thanks for this thread and manual.

 

[spock58]

I ran into a similar issue with an older Honda ATV, no spark & all the testing done wasn't successful. In the end, the part that had failed turned out to be the voltage regulator. This wasn't explained in any of the manuals & came as a surprise. Ended up being a cheap enough fix after many hours of troubleshooting! Hope this helps.

[Bobbles]

Hmmm, it might be next on the list, they are quite cheap.

[qcm413]

about mine, i have replaced the pickup coil to repair this problem. Brand name: RM Stator

[briantutt]

do you have a link to where to find it?

[qcm413]

after one week then i have replaced a CDI and it solve the problem, i have install Chinese model with some position changing in wire connector.

https://rmstator.com/en_us/rm00108 voila 😎