KTM 790 takes a few tries to start

Discussion in 'Parallel World (790/890)' started by doctorblanco, Sep 10, 2019.

  1. spartanman

    spartanman regret minimizer

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    I crack the throttle slightly and give it a touch more when cranking. Starts first time. If there's a factory fix down the road I'll get it, but in the meantime, no big deal.
    #21
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  2. Beshar

    Beshar Adventurer

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    Can you who have problems check which software version you have? It’s in the settings menu.
    #22
  3. Smashy

    Smashy Been here awhile

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    #23
  4. Some_Dude

    Some_Dude Been here awhile

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    I’m on 1V27.

    One thing I’ll point out is that if you kill the engine using the kill switch and leave it in the off position, when you power the bike back up using the key the fuel pump doesn’t turn on until the kill switch is in the on position.

    So... if you start the bike by going from off to start the fuel pump doesn’t have time to prime the line.
    #24
  5. Smashy

    Smashy Been here awhile

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    I thought I was already doing this, but I guess I was still holding it for too long. Yesterday I tried pressing and immediately letting go for the first start of the morning and it started up and stayed running on the first try. It's been pretty warm the last few days, I'm waiting for a colder morning to properly test this.
    #25
  6. Motopumps

    Motopumps Long timer Super Supporter

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    I had the same experience, thinking it was my button pushing technique, but it turns out it was pretty random. Cold weather seems to matter. Mine starts the first time about half the time now with 3100 miles on the clock. I am guessing the combustibility of the fuel you are using matters more than how you push the button. Hoping KTM has a software update that addresses this sooner than later. Makes me crabby when it won't start on the first try.
    #26
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  7. Night Crawler

    Night Crawler Been here awhile

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    I remember reading this same issue in the 1090 forum. Most people said it went away when they changed the fuel filters.
    #27
  8. Motopumps

    Motopumps Long timer Super Supporter

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    Doubt that is the problem. This has been an issue from zero miles. The fuel filter and fuel pump problems on the 1090s, 1190s and 1290s is a well documented problem with recalls, etc. The fuel filter and fuel pump on the 790 is a different part number: 63507088000 (790) vs 60307088000 (1290)

    Rob
    #28
  9. [Art]

    [Art] Been here awhile

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    #29
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  10. Motopumps

    Motopumps Long timer Super Supporter

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    I believe the fuel filter portion is a red herring.

    I work part time at a KTM dealership and have done a bunch of recalls on the 1090/1190/1290s and the issues there were fuel pumps, not filters. We have never seen a new bike with a clogged filter. There is even confusion on the internet about the color of the filter. They are black when wet (doesn't mean clogged). They turn white again when dried out. Checking the fuel filter on one of these bikes is not trivial.

    Rob
    #30
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  11. [Art]

    [Art] Been here awhile

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    Updated. Is this better?

    If this doesn't start the engine every time, or if the engine stalls right away, check your fuel filter for contamination and the pressure at the fuel pump (or ask your dealer to do it). Note: Filters are black when wet, white when dry: don't assume a dark filter is a dirty one.
    #31
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  12. Motopumps

    Motopumps Long timer Super Supporter

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    Looks good. Thanks for creating that FAQ. I have referred to it often.
    Rob
    #32
  13. Smashy

    Smashy Been here awhile

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    I think the fuel filter contamination is just a guess, and in my opinion it's not the cause. My bike has been doing this since brand new, which rules out fuel filter contamination. My guess is that this is a software issue, and we just need to wait for KTM to come out with a software update to address this.
    #33
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  14. Motopumps

    Motopumps Long timer Super Supporter

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    Agreed. That is what I was trying to communicate. I do not believe the fuel filter has ANYTHING to do with this issue.
    Rob
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  15. dewaynehasty

    dewaynehasty Been here awhile

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    I live in Florida where a cool day is 95 degrees and have the same issue. The funny thing is I took the bike to CO for a week in September at an elevation of 7300 and never had the issue. It started right up every morning. When I got back from CO, trailered the bike, with the same fuel in the tank, the issue happens again.

    It is annoying but not a big deal.
    #35
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  16. Thumper Dumper

    Thumper Dumper Been here awhile

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    Agreed, if it was a fuel filter why would it only happen on the first start of the day.
    #36
  17. windblown101

    windblown101 Long timer Supporter

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    Agreed. I mentioned the other day mine had started on the first attempt for the last couple of weeks. I figured the coldstart adaptation had finally worked itself out. But I was also on a long trip out west at the time... I started it up yesterday morning at the house (70 degrees) and it required three attempts. Today it started on the first attempt at the house (50 degrees).

    I dunno, seems like the cold start is programmed just a tad bit lean. That might explain why it starts better at altitude when cold... Maybe.

    I've gotten pretty numb to it. 11k and change on the bike so far and it has never has never failed to start yet so it doesn't annoy me like it used to.
    #37
  18. Motopumps

    Motopumps Long timer Super Supporter

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    Yeah, pretty random for me at this point. Started right up this morning at 40 degrees f, then when I went to lunch, it took two tries at 70 degrees. Going to move on at this point. Not a show stopper.

    Rob
    #38
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  19. markbxr400

    markbxr400 Been here awhile Supporter

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    I was having similar issues with starting the bike. Tried the short press of the starter button mentioned above, and it works 90% of the time for me.
    #39
  20. Gordon Bennett

    Gordon Bennett Just you wait

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    The main culprit is the Euro 6 emissions regulations which have banned cold start enrichment routines in all engines.
    So don't expect a fix from KTM.
    #40