TRC is primarily funded by ad revenue. If you like the content you find here, don't block the ads check them out instead. Thank you.
Page 1 of 3 123 LastLast
Results 1 to 15 of 33

Thread: KTM EXC 250 - Starting Problem

  1. #1
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default KTM EXC 250 - Starting Problem


    TRC is primarily funded by ad revenue. If you like
    the content you find here, don't block the ads check
    them out instead. Thank you.
    Hi Guys,

    I recently bought a 2002 ktm exc 250. When I bought the bike I test road it and everything seemed fine with it, the guy put the choke on kicked it over a few times and it started fine. (I checked it wasnt hot before he started it).

    When I got the bike home (a few days later after he Mot's it) I rode it round my field a few times and it cut out..... Turns out the fuel was turned off - they must of done that during the mot.

    Since that happened its been a absolute B*tch to kickstart even with the choke on. When it does start, it sounds really 'lumpy' and cuts out after about 30 secs and wont start again. It also cuts out when I put it into first.

    Do you think the carb will be full of crap now because I ran the bike with the fuel set to 'off'?

    Any suggestions would be much appreciated.

    Pete

  2. #2
    Really Bored
    Join Date
    Jan 2008
    Posts
    4,369
    Like
    386
    Liked 430 in 204 posts
    Blog Entries
    46

    Default Re: KTM EXC 250 - Starting Problem

    First off, is it two or four stroke?

  3. #3
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Sorry, It's 2 Stroke

  4. #4
    Really Bored
    Join Date
    Jan 2008
    Posts
    4,369
    Like
    386
    Liked 430 in 204 posts
    Blog Entries
    46

    Default Re: KTM EXC 250 - Starting Problem

    Draining the carb won't hurt.

    Check you have good fuel.

    Check plug is seated properly and producing a spark.

    I give mine one or two twists of the throttle, before kicking it over, and a little twist of throttle when kicking. Usually have the choke on, until it warms up.

  5. #5
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Thanks for your response.

    Ive drained the carb and took out the 'drain' (17mm bolt) and that had a large black flake in it and a bit of dirt so I gave it a clean out and screwed it back on.

    I will put fresh fuel in it tomorrow and check for a spark (probably just buy a new spark plug as I don't know when it was last changed - am I correct in thinking the gap on the spark plug should be 0.60mm?)

    Out of curiosity, how long do you personally normally leave the choke on for?

    Thanks,

  6. #6
    Should Get Out More Tomcat's Avatar
    Join Date
    Dec 2007
    Location
    Where I want to be.
    Posts
    33,947
    Like
    1,654
    Liked 2,295 in 1,177 posts

    Default Re: KTM EXC 250 - Starting Problem

    Quote Originally Posted by petektm91 View Post
    Out of curiosity, how long do you personally normally leave the choke on for?

    Thanks,
    I've got a 2012 250 EXC. It doesn't particularly like running cold though it starts fine. Once it gets into the "not cold, but not warm yet" zone it gets a bit sulky and I find it best to keep the revs up and ride it as soon as possible, choke off after a few hundred yards. My kid does enduro on it, the rules are cold engine start so he warms it up for maybe 15-20 seconds then hits the track.

    Obviously if you had shit in the carb that wouldn't help, but slow running is controlled by the idle circuit so you should really look at that jet not just any big bits in the float bowl.

    However I suspect your problem is the plug. Mine hasn't eaten one yet but I have heard it's a fairly common thing, they just foul/eat plugs and all you can do is put a new one it.

  7. #7
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Thanks for the info.

    Ill have a look at adjusting the idle circuit.

    Can you recommend the best spark plug make to use?

  8. #8
    Should Get Out More Tomcat's Avatar
    Join Date
    Dec 2007
    Location
    Where I want to be.
    Posts
    33,947
    Like
    1,654
    Liked 2,295 in 1,177 posts

    Default Re: KTM EXC 250 - Starting Problem

    So far we're still using the plug that came with the bike but at 80hrs use it's about due for a piston change so I'll probably swap the plug when I do that. I've bought a NGK gold-palladium plug one grade hotter than standard. They generally fit coldish plugs as OE so the fast boys who use it flat out don't melt them, but for most riders a slightly hotter one will be fine and resist fouling better.

  9. #9
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Ive had a look for the spark plug you mentioned and I cant seem to find it. Where do you normally get yours from?

    Do you know if a owners manual for a 2 stroke 2002 ktm exc 250 exists? Ive found a PDF copy for a 2008 online but I'm not sure how correct it is for my bike.

    Is Fully Synthetic 5W/40 oil the correct stuff to use? This is the first 2 stroke Ive owned ... if you hadn't already guessed!!

    Thanks,

    Pete

    Pete

  10. #10
    Should Get Out More Tomcat's Avatar
    Join Date
    Dec 2007
    Location
    Where I want to be.
    Posts
    33,947
    Like
    1,654
    Liked 2,295 in 1,177 posts

    Default Re: KTM EXC 250 - Starting Problem

    You can get some manuals here: KTM Manuals & Documents

    The internets suggest the plug to go for is NGK BR7ES but it might be an idea to check that with a KTM dealer.

    There's a pretty good online parts fiche here: OEM Parts

    And yes, full synthetic is best. It's the most expensive but gives the best protection, and these engines kinda need that Check it's for premix rather than injector. KTM recommend Motorex but other brands are available I like Silkolene Comp 2. Ratio to use is 50:1.

  11. #11
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Thanks for your help, much appreciated.

    Today I changed the spark plug, took all the fuel out the tank and but fresh in (with oil). I was amazed how much shit there was at the bottom of the fuel tank!

    But it still had a really lumpy idle and would die quite quickly. Turns out (after looking in a 2008 manual) that the idle postion was too low. I adjusted it slightly and now it doesnt cut out!! Ive only adjusted the idle screw slightly but was wondering if there is anything else I need to adjust?

    What should the revs be on when idling?

    Thanks

  12. #12
    Should Get Out More Tomcat's Avatar
    Join Date
    Dec 2007
    Location
    Where I want to be.
    Posts
    33,947
    Like
    1,654
    Liked 2,295 in 1,177 posts

    Default Re: KTM EXC 250 - Starting Problem

    Dunno, mine doesn't have a rev counter. But most strokers tend to idle around 1200rpm I think.

    If you haven't already, take the carb off and give it a real good clean out to make sure there's no shit in the jets, particularly the slow running side. Then reset all the adjuster screws to where the manual says they should be.

  13. #13
    A Bit Bored
    Join Date
    Sep 2013
    Posts
    15
    Like
    0
    Liked 0 in 0 posts

    Default Re: KTM EXC 250 - Starting Problem

    Im going to take the carb off this week and give it a clean.

    What engine oil do you use? and how often would you recommend changing it?

  14. #14
    Really Bored
    Join Date
    Jan 2008
    Posts
    4,369
    Like
    386
    Liked 430 in 204 posts
    Blog Entries
    46

    Default Re: KTM EXC 250 - Starting Problem

    Putoline/Motorex stuff - it's not widely available in "normal" bike shops i.e road bikes. Iirc the manual says something like 40hrs for trail riding etc, 20 for racing.

  15. #15
    Should Get Out More Tomcat's Avatar
    Join Date
    Dec 2007
    Location
    Where I want to be.
    Posts
    33,947
    Like
    1,654
    Liked 2,295 in 1,177 posts

    Default Re: KTM EXC 250 - Starting Problem

    Really? I should RTFM, I've had the same gearbox oil in since new, that's 80 racing hours so far.

    I've had pretty good experience with Silkolene SRG75 in the past, would that do the job here or are they sensitive on oil?

Page 1 of 3 123 LastLast
Go Back to Forum My Forum

TRC Affiliates - Help TRC make a small amount of commission