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Weak spark cant figure it out

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So I bought this 1996 XR250L from a guy that said it needed a stator.  Well I checked the stator out and it was Black/Red wire to Ground 131.6 ohms and Red to Yellow wire 0.8 Ohms

Checked spark plug it was good/new and also tested with another one. 

Checked out the pulse generator and it was bad so I bought a new one (well apparently this 96 was made in EARLY EARLY 96 and used an older style pulse generator) which they dont make new anymore.  Bought one off ebay checked it out and yes I have spark but very very weak.  Checked the coil out it was giving me weird numbers so bough a new one.  Same thing weak spark so I put the old one back on.  

From what Im told there isn't a good way to check the CDI box so I replaced it with a CDI box from a CRF50 Honda and I still got a weak spark.

 

Im running out of things to check any info and tops would be greatly appreciated.

 

 

by weak I mean holding it in your hand kicking it over and feeling a tingle.  Ive been zapped by good ones before OUCH LOL

 

Thanks in advance 

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The 250L stator is three phase and has three yellow wires coming out of it. The regulator/rectifier converts this to 12volts DC to charge the battery.  Everything runs off the battery.  It's a street bike system with lots of power.  

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The 250L stator is three phase and has three yellow wires coming out of it. The regulator/rectifier converts this to 12volts DC to charge the battery.  Everything runs off the battery.  It's a street bike system with lots of power.  

 

Isn't the firing coil... and three yellow charging/lighting wires separate? 

Edited by n2omike

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Isn't the firing coil... and three yellow charging/lighting wires separate? 

 

No, these don't have a separate firing coil.   That's a dirt bike design.

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So I bought this 1996 XR250L from a guy that said it needed a stator.  Well I checked the stator out and it was Black/Red wire to Ground 131.6 ohms and Red to Yellow wire 0.8 Ohms

Checked spark plug it was good/new and also tested with another one. 

Checked out the pulse generator and it was bad so I bought a new one (well apparently this 96 was made in EARLY EARLY 96 and used an older style pulse generator) which they dont make new anymore.  Bought one off ebay checked it out and yes I have spark but very very weak.  Checked the coil out it was giving me weird numbers so bough a new one.  Same thing weak spark so I put the old one back on.  

From what Im told there isn't a good way to check the CDI box so I replaced it with a CDI box from a CRF50 Honda and I still got a weak spark.

 

Im running out of things to check any info and tops would be greatly appreciated.

 

 

by weak I mean holding it in your hand kicking it over and feeling a tingle.  Ive been zapped by good ones before OUCH LOL

 

Thanks in advance 

 

 

Do you have the wires to the coil backwards?  If you have the (+) on the (-) and vice versa, it will give a really weak spark.  Have you tried switching them and trying it? 

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It sounds to me like the bike may have the wrong stator.  I don't think the L CDI will work off AC current and you may be burning some expensive parts. 

 

The owner said it needs a stator and that is sounding like a true statement.  Does it have the original flywheel or was that changed?

 

This could be a nightmare.

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Try cleaning the alternator with some CLR or another rust-removing cleaner. Older bikes tend to have rusty coils and or magnets. If you clean them it might work better. It sounds like your problem is worse than a little rust, sorry I can't help any further.

 

The coils on my 91 XR100R were rusted and this is how I fixed it.

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First of all thanks for all the replys

It must have been converted over sometime during its life because it doesnt have a battery.  It has the normal 250r pink black/red yellow wires.  I did switch the wires over on the coil and that didnt work. :(

 

I think this is a nightmare but Ive worked it out before.    Ok so what do I need to look for in the fly wheel?   I did have the cover off on that side once just to see if I could see any burnt or odd looking coils on the stator.

 

Im not to worried about the fuel delivery just yet untill I can get a good spark.  

 

Again thanks for all the help and hang in there with me and we will have another XR back on the road.....well dirt LOL

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Maybe it never ran after the stator was changed.  Does the regulator/rectifier have three yellow wires?

 

If you have an R stator, then you may need an R CDI and an R coil.  You need to determine which components are R and which are L and then complete the system as one or the other.

 

These bikes do have a tiny spark since it's a wasted spark ignition system.  This means the spark fires at every TDC just like a two-stroke, hence the term "wasted spark."

 

Blown components can get very expensive.

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This is coming from the stator 

 

946014_10202197702894169_136115591_n.jpg

 

 

 

Wires coming from rectifier 

 

1238369_10202197703334180_1530895076_n.j

 

 

Wires going to coil  and on bottom left of this picture are wires coming from pulse generator on the clutch side of engine

 

1377502_10202197703614187_2007420786_n.j

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These are the wires going to the CDI box

 

1378862_10202197704014197_683416651_n.jp

 

This is the Pulse Generator/ pulser / Pick up coil what ever you want to call it

 

 

1376416_10202197738255053_657275158_n.jp

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Has the bike run since you've had it?

Or does it not run at all and you think its from a weak spark?

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Is there a resistor in the spark plug boot(?)

 

Heck if were me and I had spark I would be putting fuel in it and trying to start it...

 

Not a bad idea to clean the carb too. As said before I would look for fuel delivery...

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No experience with the XLs but if it is an XL then the electrics are DC, including the ignition, and you need a good battery for the ignition to work. The alternator only charges the battery.

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No It hasnt ran since I bought it.  The spark is WAY to weak.  Doesnt even hurt when holding the spark plug gap in my hand and kicking it over.

 

  Ive tried shooting Carb cleaner straight through the carb into the combustion chamber.    

 

Previous owner took the resistor out of the spark plug boot.  Ive switched the coil over from a known good Coil and same results.  

 

I dont see any where too even hook up a battery.

 

I think I'll check all the grounds and see if I can check how much voltage it's getting to the coil when I try to kick it over.

 

I might even try to hook up a battery charger to the (+) and (-)  coil and see if I can get a hotter spark But I dont want to damage anything I'll only put it on 4amp or 6 amp which ever the smallest one I have (not the 25amp or 40 amp LOL)

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