Possible bad stator.?

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JZ05220r
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Possible bad stator.?

Post by JZ05220r »

My 220 seems to run fine for the first 5-10 minute of riding then starts running bad. The idle start to be extremely inconsistent and nearly impossible to adjust. The exhaust note changes (gets very crackly and lopey sounding) and sounds like it’s running out of gas getting on and off the pipe. I am thinking it might be a bad stator. I’m going to perform a leak down test first to rule out an air leak, but if all is well I am going to look into electrical issues as a possibility. Out of curiosity will I need to solder if I were to swap in a new source coil? Thanks
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Re: Possible bad stator.?

Post by SS109 »

Don't forget to check your ignition coil as well. Sometimes when they go bad they'll be fine when cool but start shorting once they get hot. Same with the plug wire itself.

Yeah, stators coils have to be soldered in.
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Re: Possible bad stator.?

Post by JZ05220r »

SS109 wrote: 01:17 am Sep 18 2022 Don't forget to check your ignition coil as well. Sometimes when they go bad they'll be fine when cool but start shorting once they get hot. Same with the plug wire itself.

Yeah, stators coils have to be soldered in.
Thanks for the response. I am not very good with electrical. However I do have a soldering iron. Do I just cut the old wire off and solder it to where I made the cut? I’m also thinking about what I should use to cover up the solder so it’s not exposed? Not sure what to use besides shrink wrap. Thanks again
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Re: Possible bad stator.?

Post by SS109 »

Yeah, cut off the lead wire close to the same length that's on the replacement coil and then solder wiring to the new coils lead wire. Just use a little marine rated heat shrink on it and you'll be good.
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Re: Possible bad stator.?

Post by JZ05220r »

SS109 wrote: 02:09 pm Sep 18 2022 Yeah, cut off the lead wire close to the same length that's on the replacement coil and then solder wiring to the new coils lead wire. Just use a little marine rated heat shrink on it and you'll be good.
👍thanks
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Re: Possible bad stator.?

Post by JZ05220r »

SS109 wrote: 01:17 am Sep 18 2022 Don't forget to check your ignition coil as well. Sometimes when they go bad they'll be fine when cool but start shorting once they get hot. Same with the plug wire itself.

Yeah, stators coils have to be soldered in.
Would it be worth just swapping out the ignition coil in this instance as the problem is intermittent? My list 1. Leak down 2. Source coil replacement 3. Ignition coil and spark plug wire replacement. Also wondering if it’s best to go with an oem ignition coil or if their are cheaper alternatives. Sorry about all the questions! Just trying to solve this issue and learn along the way. Thanks
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Re: Possible bad stator.?

Post by JZ05220r »

JZ05220r wrote: 10:28 pm Sep 18 2022
SS109 wrote: 01:17 am Sep 18 2022 Don't forget to check your ignition coil as well. Sometimes when they go bad they'll be fine when cool but start shorting once they get hot. Same with the plug wire itself.

Yeah, stators coils have to be soldered in.
Would it be worth just swapping out the ignition coil in this instance as the problem is intermittent? My list 1. Leak down 2. Source coil replacement 3. Ignition coil and spark plug wire replacement. Also wondering if it’s best to go with an oem ignition coil or if their are cheaper alternatives. Sorry about all the questions! Just trying to solve this issue and learn along the way. Thanks
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Re: Possible bad stator.?

Post by SS109 »

Normally I would just swap in a known good ignition coil and test it. That said, aftermarket ones are not expensive at all so totally up to you over OEM.

I would do the leakdown first, then test the ignition and source coils. test both coils cold and then run it until it starts messing up then immediately retest them.
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Re: Possible bad stator.?

Post by Slick_Nick »

Before you go soldering wires and swapping parts, why don't you simply TEST the various components to see what's actually wrong? All of the resistance readings are listed in the service manual, and The only part you'll really need to remove in order to test it is the seat.
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Re: Possible bad stator.?

Post by JZ05220r »

Slick_Nick wrote: 09:21 am Sep 19 2022 Before you go soldering wires and swapping parts, why don't you simply TEST the various components to see what's actually wrong? All of the resistance readings are listed in the service manual, and The only part you'll really need to remove in order to test it is the seat.
Ok, I don’t really feel too comfortable running the bike until after the leakdown test. The bike suddenly runs loud and raspy like it’s old and beat up. It suddenly lacks smooth power, the idle also picks up then goes very low, pick ups again and so on. If that checks out I will test the ignition system on the bike cold and hot per the manual. I was very alarmed to see the ground strap of the spark plug had a slightly course white dust like coating on it when my jetting is very close, looked like it ran very hot. Thanks.
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Re: Possible bad stator.?

Post by JZ05220r »

Slick_Nick wrote: 09:21 am Sep 19 2022 Before you go soldering wires and swapping parts, why don't you simply TEST the various components to see what's actually wrong? All of the resistance readings are listed in the service manual, and The only part you'll really need to remove in order to test it is the seat.
When measuring the exciter coil lead terminals I have .3 ohms to chassis ground on the black and 309 ohms on the white/red. When checking the primary windings on the ignition coil I got .5 ohm. The secondary was 12 k ohms. Is something wrong there?
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Re: Possible bad stator.?

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JZ05220r wrote: 06:05 pm Sep 19 2022
Slick_Nick wrote: 09:21 am Sep 19 2022 Before you go soldering wires and swapping parts, why don't you simply TEST the various components to see what's actually wrong? All of the resistance readings are listed in the service manual, and The only part you'll really need to remove in order to test it is the seat.
When measuring the exciter coil lead terminals I have .3 ohms to chassis ground on the black and 309 ohms on the white/red. When checking the primary windings on the ignition coil I got .5 ohm. The secondary was 12 k ohms. Is something wrong there?
Well, what's the service manual say?
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Re: Possible bad stator.?

Post by JZ05220r »

Slick_Nick wrote: 08:24 am Sep 20 2022
JZ05220r wrote: 06:05 pm Sep 19 2022
Slick_Nick wrote: 09:21 am Sep 19 2022 Before you go soldering wires and swapping parts, why don't you simply TEST the various components to see what's actually wrong? All of the resistance readings are listed in the service manual, and The only part you'll really need to remove in order to test it is the seat.
When measuring the exciter coil lead terminals I have .3 ohms to chassis ground on the black and 309 ohms on the white/red. When checking the primary windings on the ignition coil I got .5 ohm. The secondary was 12 k ohms. Is something wrong there?
Well, what's the service manual say?
The primary spec is 16 - .24 Ohm. The secondary is 5.0-7.6 W x 1k ohm. I got too high of readings for both. I guess that warrants a replacement ignition coil but unsure why they are reading high.
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Re: Possible bad stator.?

Post by John_S »

My 20 year old coil and new in the box OEM coil read about the same. Both read .4 primary which according to the manual is out spec. Secondary is 6.71 new and 6.74 old.
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Re: Possible bad stator.?

Post by Slick_Nick »

For how cheap ignition coils are, and how easy they are to replace, why not start there?
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Re: Possible bad stator.?

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Slick_Nick wrote: 08:59 am Sep 21 2022 For how cheap ignition coils are, and how easy they are to replace, why not start there?
I ordered one last night. I’ll see it goes. I can turn my air screw in all the way and the idle still goes up then eventually back down then up again. I can’t see how an electrical problem could cause that idle issue but I can see how it could cause issues while riding in gear. Leak down test is tomorrow while I wait for the new ignition coil
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Re: Possible bad stator.?

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JZ05220r wrote: 05:36 pm Sep 21 2022
Slick_Nick wrote: 08:59 am Sep 21 2022 For how cheap ignition coils are, and how easy they are to replace, why not start there?
I ordered one last night. I’ll see it goes. I can turn my air screw in all the way and the idle still goes up then eventually back down then up again. I can’t see how an electrical problem could cause that idle issue but I can see how it could cause issues while riding in gear. Leak down test is tomorrow while I wait for the new ignition coil
Well you may have some jetting issues going on as well, but best to just tackle one thing at a time and see what does what.
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Re: Possible bad stator.?

Post by JZ05220r »

:lol:
Slick_Nick wrote: 09:32 am Sep 22 2022
JZ05220r wrote: 05:36 pm Sep 21 2022
Slick_Nick wrote: 08:59 am Sep 21 2022 For how cheap ignition coils are, and how easy they are to replace, why not start there?
I ordered one last night. I’ll see it goes. I can turn my air screw in all the way and the idle still goes up then eventually back down then up again. I can’t see how an electrical problem could cause that idle issue but I can see how it could cause issues while riding in gear. Leak down test is tomorrow while I wait for the new ignition coil
Well you may have some jetting issues going on as well, but best to just tackle one thing at a time and see what does what.
For the leakdown test I positioned the piston at BDC and pressurized to 6psi. After 6 minutes it had only lost 1 psi. I think that’s an acceptable loss. Going to try swapping the ignition coil first and after I am going to triple check the carb. One thought that came to mind is my current set up. FRP porting, RB head, 35mm carb along with a full fmf system (rev). I had the RB head done before and other engine or carb modification. Could my setup be causing the engine to run rough suddenly while riding? Thanks
Last edited by JZ05220r on 08:55 pm Sep 22 2022, edited 2 times in total.
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Re: Possible bad stator.?

Post by JZ05220r »

John_S wrote: 11:08 am Sep 20 2022 My 20 year old coil and new in the box OEM coil read about the same. Both read .4 primary which according to the manual is out spec. Secondary is 6.71 new and 6.74 old.
Good to know
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Re: Possible bad stator.?

Post by JZ05220r »

SS109 wrote: 06:35 am Sep 19 2022 Normally I would just swap in a known good ignition coil and test it. That said, aftermarket ones are not expensive at all so totally up to you over OEM.

I would do the leakdown first, then test the ignition and source coils. test both coils cold and then run it until it starts messing up then immediately retest them.
I did the leakdown test and the results were good so onto the next thing I guess. Thanks
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