07 ec 250 has started to miss at first it would miss mid range now it is more on top hold it wide open and it spits and carries on.I put a new coil on with a new plug wire. Did not help. I have checked out stator and pick up coil all test out fine. I don't think it is jetting my reason why is I hooked up my inductive timing light and when it starts missing the light goes out .Like there is an interruption in the flow of juice.i also have unplugged my voltage reg and no change the only thing that does change it is when I put from rain to sunny mode.It runs much better in the sunny mode.I had a 01 that had very similar issues and it was the cdi. Starting to think it is the cdi again.I've been told that a KTM cdi is the same going to try one tonight before I shell out the money for a new one.Any thoughts ?
Bike running poorly need some help!!!!
- Thread starter Silver
- Start date
noobi
New member
I had a problem similar to this on my 07 125, it would miss/splutter and run very poorly in most of the mid range but would idle and run at around idle speed ok but as soon as the engine sped up it would run poorly all through the mid range up to the top end where it would start to run just ok-ish.
The problem was that one of the cdi connection was loose and dirty, so I pulled all connections, cleaned them with electrical contact cleaner, and found that one was very floppy in its fit, so squashed the female joiner so it held the pin better, taped up all the joins, this fixed the problem and never had an issue with the electrics since.
This was the last thing I did before I would have taken the bike to the shop and they would have charged me for all the checks I did myself.
It also sounds like it could be a partially blocked jet in the carb, although that wouldnt cause the timing light issue, but its just one more thing to remove from the equation.
Good luck
The problem was that one of the cdi connection was loose and dirty, so I pulled all connections, cleaned them with electrical contact cleaner, and found that one was very floppy in its fit, so squashed the female joiner so it held the pin better, taped up all the joins, this fixed the problem and never had an issue with the electrics since.
This was the last thing I did before I would have taken the bike to the shop and they would have charged me for all the checks I did myself.
It also sounds like it could be a partially blocked jet in the carb, although that wouldnt cause the timing light issue, but its just one more thing to remove from the equation.
Good luck
I may have had the same issue last night the last thing I did was clean up the plug with electric contact cleaner and tonight it seemed better.Ran the same with my cdi and a borrowed ktm one.Heading to the National enduro tomorrow only an 1 hr and 15 min drive 
.I'm hoping it runs good all day.I did clean my carb tonight and all was fine.Went back to my hot weather jetting.178 main 40 pilot. 1.5 air screw. Ran better time will tell.
.I'm hoping it runs good all day.I did clean my carb tonight and all was fine.Went back to my hot weather jetting.178 main 40 pilot. 1.5 air screw. Ran better time will tell.Running poorly
Hi Silver,
Ran into the same problem two years ago with Jim Senecals bike, (New England Champ), ran good for two laps then quit. Put in new CDI, has been fine. Billy Burns, when he was on GG two years ago had the same problem. Ran better in sun mode than the other. CDI problem. If you get a chance to check this site before the National talk to Rich Smith (Smiths Power Sports) and tell him you got an e-mail from me. He may or may not have a CDI with him but is worth a shot.
Brian De Vries
Lda Racing
Hi Silver,
Ran into the same problem two years ago with Jim Senecals bike, (New England Champ), ran good for two laps then quit. Put in new CDI, has been fine. Billy Burns, when he was on GG two years ago had the same problem. Ran better in sun mode than the other. CDI problem. If you get a chance to check this site before the National talk to Rich Smith (Smiths Power Sports) and tell him you got an e-mail from me. He may or may not have a CDI with him but is worth a shot.
Brian De Vries
Lda Racing
Your problem is a no spark under load problem. The inductive light is triggered when the electromagnetic field of the spark going through the wire is sensed by the inductive lead on the timing light. The light not flashing means that the spark is going somewhere else (not through the wire) or it's not sparking at all. The CDI is a possibility for the not sparking at all but I would also check the plug wire and terminal connections for any place it may touch and be grounding out. This will look like a lead pencil mark on the wire or terminal caused by carbon tracking from the spark jumping. I wouldn't do anything to the fuel system until you resolve the spark problem. You may create a new problem before you fix the old one. Good luck and happy hunting.
The new coil I put on had a new plug wire on it. So plug wire is out. I tried a cdi out of an 06 ktm 300 ran the same. I'm going to unhook kill switch next .I cleaned up the ground. I got a fly wheel puller so I can check stator out. Very frustrating. Sat. I fouled a plug put in a new one rode it like I stole it for 3 miles and new plug was already black.This is my 2nd Gas Gas and both have had electrical issues.
Thankfully on Sunday for the Jack Pine Nat. a friend loaned my his 2010 ktm 300 with a rekluse. Man I hate to admit that bike was sweet very well set up he is a AA rider. Any way please keep the ideas coming I'm about ready to pull my hair out .
Thankfully on Sunday for the Jack Pine Nat. a friend loaned my his 2010 ktm 300 with a rekluse. Man I hate to admit that bike was sweet very well set up he is a AA rider. Any way please keep the ideas coming I'm about ready to pull my hair out .I have seen cases where there was carbon tracking on a plug and plug boot and if both weren't replaced at the same time the carbon tracking would follow the path still there until they were both ruined again. This won't be the case if you put a plug in at the same time as you replaced the coil and the wire. You would also be able to see a dotted or solid line on the old plug and inner plug boot as if you drew on it with a pencil. Weak staters can be hard to confirm without replacing them, I prefer it when they quit all together because a weak one may test ok but run poorly just like an intermittent CDI.
Sounds like you have done everything in the right order so far. I had a case on another system similar to this where the stator pole pieces were hitting the inductive part of the stator and it damaged the CDI module so I had to replace both but that is pretty rare.
Last night I started bike in the garage with lights off looking for a wire shorting out on the frame. What I found was a ring of spark around my spark plug cap nice bright blue. I have 2 coils both with plug wire and cap and both do this. I cleaned cap and put in a new plug still doing it .Cut off a 1/4 in of wire reinstalled cap still does it.Going to get a new cap and see if that helps.Puzzled as how 2 coils with wires and caps would both do the same thing.With one being brand new.
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Running poorly
Quick hint,
If spark plug is black and sooty it is an electrical problem, if the plug is wet it's a fuel problem. Stator problems can be tough to diagnose. The real way to do it is when the engine is hot and the bike runs bad that is when you test the resistance with an ohm meter from the stater. Previously stated Jim Senecals problem was an easy fix. All I did was pull the seat off, start the bike which fired up immediatly and then I started moving wires around by the CDI. At that point the bike quit running. I knew then the problem was a connection from the wiring to the CDI box. New box, no problems.Any more questions please contact me.
Brian DeVries
LDA Racing
LDAmarketing@live.com
Quick hint,
If spark plug is black and sooty it is an electrical problem, if the plug is wet it's a fuel problem. Stator problems can be tough to diagnose. The real way to do it is when the engine is hot and the bike runs bad that is when you test the resistance with an ohm meter from the stater. Previously stated Jim Senecals problem was an easy fix. All I did was pull the seat off, start the bike which fired up immediatly and then I started moving wires around by the CDI. At that point the bike quit running. I knew then the problem was a connection from the wiring to the CDI box. New box, no problems.Any more questions please contact me.
Brian DeVries
LDA Racing
LDAmarketing@live.com
This "Ring of Fire" is a great Johnny Cash song but it is not normal at all for secondary ignition. I would be suspecting a problem with some kind of contaminate on your plugs like maybe anti seize in your plug socket that is getting on all your plugs.
Everybody told me cdi's either work or they don't. Well i chased my tale for the better part of a month. Bought parts i didn't need. Well I 'm here to tell ya cdi's can cause the issue I was having. Picked up a used cdi (thanks bbdirtbiker)
put it in friday raced today no fouled plugs no cutting out ran great plug back to its nice tan color. So any of you that thinks a cdi either works or it doesn't I got one that works but not like it should for sale Thanks for all the help. By the way I had a similar issue with my 01 and a cdi fixed that one also. I should just got a cdi to start with. I'll be trusting my gut instinct from now on.
put it in friday raced today no fouled plugs no cutting out ran great plug back to its nice tan color. So any of you that thinks a cdi either works or it doesn't I got one that works but not like it should for sale
Thanks for all the help. By the way I had a similar issue with my 01 and a cdi fixed that one also. I should just got a cdi to start with. I'll be trusting my gut instinct from now on.
twowheels
New member
Everybody told me cdi's either work or they don't. Well i chased my tale for the better part of a month. Bought parts i didn't need. Well I 'm here to tell ya cdi's can cause the issue I was having. Picked up a used cdi (thanks bbdirtbiker)
put it in friday raced today no fouled plugs no cutting out ran great plug back to its nice tan color. So any of you that thinks a cdi either works or it doesn't I got one that works but not like it should for sale
Well done Mike. I bet it feels good to be off that pumpkin
The cdi used before was from a 06 ktm 300 was told they were the same . Now i don't think so. Maybe it was something else I did not sure. Trust me i checked everything from bad crank bearings to all the wires on the bike. the new box seemed to cure it. I rode 90 miles this weekend between my race and the family enduro I rode with my wife and kids. Never fouled a plug before I could maybe get 20 miles before a plug was gone.My 01 lost a cdi also not quite the same as this but close enough I should have just went with the cdi.But that KTM one through me for a loop. Not sure about the spark on the outside of plug cap last time i checked mine it was gone .The bike has to be reved up pretty good to see it.Try yours in a dark garage and let me know the results.
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