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KTM 250 EXC Starting Problems

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Aug 6, 2001
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#1
Hi All,

Myself and a friend both own KTM 250 EXC's (1999 & 2000) and find them extremely difficult to start from cold, i.e. when they haven't been ridden for a while. Once they're warm, it's first kick all the way but getting them going can take 30 / 40 / 50 kicks...... Anyone got any bright ideas?

Thanks
 

biglou

#2
Are you too lean on the air screw or pilot? Choke pulled? Here is my drill:

Gas on, choke on, 2-3 slow priming kicks and then kick it like you mean it. When it's really cold (35-40 degrees) it may take me 5-7 kicks. Warmer and she usually fires first kick or two. I've been very lucky thus far following that routine.
 
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#3
Check the back of the owners manuel for proper jetting temp./altitude for your area. Should not be a problem to start then. I second Big Lou's starting suggestion.
 

Jim G

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#4
I just changed from the four strokes to a 2000 250 EXC. I feel that I got extremely lucky. I can unload the bike, turn the gas on (no choke), Starts first kick. I think that the previous owner had just installed a fresh top end and had the bike properly jetted. The jetting would be the first thing that I would check, if that does not take care of the problem, may be time to redo the top end. My bet would be the rings, when cold, causing a loss of compression. When warmed up, the rings expand to be a little closer to spec and allow for easier starting.
 
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#5
If they haven't been ridden for a while, turn the fuel tap on, tip the bike(s) over until some fuel runs out the overflow, choke on, no throttle, kick. Should light right up.
 
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#6
My 2000 250exc starts on the first kick with the choke and no throttle.

If they have set long, lean them over all the way over on the left hand side until the carb takes a pee and then try to start them. The will richen up the fuel mixture as it floods the carb.
 

Strick

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#7
Put in a new plug and always use fresh gas (less than 2 weeks old). Then here is my drill. Gas on, choke on, put bike in 2nd gear and rock the bike back and forth to rock the reeds. Rock the bike back and forth like the man you are and not your sister! Tip the bike towards you at say a 45' angle or so until gas start to flow out the overflow. Put the bike in neutral, and Kick it like a man while twisting the throttle say 1/8th open. If this does not start your bike you have one of these 3 problems:(assuming you have the 3 essential elements - air, fuel, spark) low compression - time for rebuild, chipped/frayed reeds, jetting issues.
 
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#8
Leaning over works great, and if it is cold try putting it in second gear and rocking the bike back and forth a little. Then try to start it, in netrual. This primes the cylinder and works great. May have to rock it twice if it is really cold.
 
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#9
so my buddy is having a similar problem bike ran fine when he put it away now kick it 1000 times pulled it with the truck nothing..has spark, everything seems to be in order..the thing that gets me is it will start when it wants and wont for a week or 2? Is this a common thing..never even rode a ktm
 
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#10
If it has good spark and good compression chances are very good that the pilot jet is plugged. A new plug, a proper cleaning of the carb and some fresh fuel will go a long ways towards making it start properly. It has nothing to do with it being a KTM.
 
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#11
so we tried the ritual of tilting the bike till it leaked alittle gas acouple slow kicks and one good one and it fired right up acouple days in a row now?? Weird but works
 
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#12
If you would clean the friggin carb :BRIGHT: you wouldn't need "rituals" to start the bike.
 
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#13
:COOCOO:well rich carbs have been clean from the start still had the issue explain that? myself I just wouldn't have got a KTM!
 
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#14
:COOCOO:well rich carbs have been clean from the start still had the issue explain that?!
Yeah, and I have a bridge to sell you.

Assuming that the carb is clean, you have good compression and good properly timed spark (I'm not BTW) and you have to dink around the way you described then the float level is WAY off, the choke circuit isn't working correctly or you have a big honkin air leak. Once again it has nothing to do with it being a KTM. Poorly maintained bikes have no geographic allegiance.
 
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