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04 CRF450r Stator no spark

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I am working on the an 04 CRF450 that has no spark. Was running fine and stupid me decided to wash it and now no spark. The exciter and pulse coil resistances are within spec, but I am only getting 30v when I kick it. The manual says it should be at least 50v. I checked/cleaned the ground at the coil (resistance values for the coil both are okay), checked for shorts/grounds in the stator, checked for bad wires, etc. I am not even getting 1v out of the CDI. I bought a new CDI thinking that I should at least be getting something there with 30v, but that wasn't it. So I am back to a bad stator, but before I order one (and wait another week) am I missing anything? It just seems odd that the stator resistance values are both good but the voltage is low. It does seem like the magnet on the flywheel is weak but I have no way to check that without buying another flywheel to compare it.

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Just put a new stator in it and no luck, getting the same peak voltage readings as I was getting on the original. New CDI and stator, I have tested all the wires for continuity and for bad grounds. I am at a loss on this thing, one thing that seems off is the magnet on the flywheel, compared to other bikes I have worked on this one seems to be weak, but since I don't have another one to check it against I don't really know. Any suggestions...?

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I don't think magnets just go bad that qiuck, but see if you can borrow one. Un hook the kill wire, the go over every single ground wire on the bike. Then if that don't work, go over every live wire. Again.

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Well, I checked and rechecked the wiring and can't find any sort of short. I connected the the kill switch wires together and got one good spark and that's it. Disconnect them and nothing, reconnect and one spark.

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Are the pick up coil connections clean? Ive seen those things covered in a iron debris goo that looks innocent enough that grounds them together and or shorts them to the flywheel itself.

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youve probably got water in the connections. Its a basic problem, but it wont go away on it's own. You need to pull the tank, access the entire harness and start cleaning like you were going to have the thing surgically implanted in your body.

One spark tells me the system wants to work, but once you get it to, the short (or open) reasserts itself and opens the coil charging circuit. The book says the exciter should make 50v, but it'll run on much less, as long as the stator is still producing voltage to charge the coil, the pulser sets off the transistors that open the circuit that fires the coil. That pulser coil only makes about 1 volt when you kick it. Thats why its susceptible to the ferrous bearing goo. 

Did you pull the CDI box and clean out that connector on both ends? And check that green ground wire on the coil too.

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I have pulled everything apart and checked continuity on all the wires between where they plug into the stator to the CDI and checked the for continuity on the green wire on the coil. I pulled the coil and scraped the frame where it mounts, cleaned the coil itself. I did manage to borrow a CDI and that's not the problem. Since I am getting similar output on both the old stator and the new and I now have two good CDI units. So I am left with something in the harness, is there another ground besides the one that attaches at the coil?

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Well I can officially say I am at a loss, put in a new coil...nothing, got a different wiring harness, still nothing..... The only thing left is the flywheel and I can't possibly see that it's the problem since I am getting power coming out of the stator......

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Water in the spark plug cap? Seems like the cap is the only common thing left. That and the plug itself...The cap is a resistor type, with about 5K ohms of resistance. And if you blasted the right side of the engine, there's a drain hole there that will direct a water blast right up the cap....

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3 hours ago, Slow and Jerky said:

Okay, finally!!!! I was able to borrow another bike to trade parts with. And low and behold the new stator was bad after all. 

 

I had a bad stator on my CR500 that mess with me for ever. It wasnt until I put the friggin thing in the oven and got it hot was I able to diagnose the open circuit in it. It'd start, run fine for five minutes and a couple seconds exactly and die, to not start again until dead cold. When cold, the stator measured perfectly. When hot, it was wide open. Zero resistance.

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