Ktm electric start problems

Discussion in 'Thumpers' started by YOGURTS SMC, Mar 2, 2013.

  1. YOGURTS SMC

    YOGURTS SMC n00b

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    Hi,Can anybody help!! Ive got a KTM 625 SMC LC4 , it runs fine kick starts fine, but wont fire up on the electric start---the engine turns over as normal but wont fire but will start with the help fron jump leads and a running car,but before everybody says its the battery am not sure for to reasons, brand new yuasa yts10 battery, and when your using the jump leads the starter turns over at about the same speed but the bike starts???,
    I think the starter motor is taking all the power and is leaving nothing for the ignition side, just like the cars in the 70 and 80s that needed a ballast resistor before the coils, Any ideas??
    #1
  2. Droptarotter

    Droptarotter Long timer

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    Still sounds like the battery to me............just because it is a new battery does not mean that it is good.
    Any way you can try another battery to see what happens?

    Good luck
    #2
  3. strongbad

    strongbad Been here awhile

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    It sounds like the battery or the connections to the battery. If the connections are clean and tight with no oxidation or corrosion, take the battery to a battery shop and have it load tested.
    #3
  4. Seikkailu_R

    Seikkailu_R Been here awhile

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    First measure voltage between battery positive and starter positive during starting.
    Should be near zero, if not, there is bad connection somewhere between battery and starter.
    Or bad solennoid.
    Also check connections on negative side.

    Remove and check starter for stuck brush and seized bearings.
    #4
  5. ericGSsti

    ericGSsti Been here awhile

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    Could be old Batt but i'd say is the Alternator in the starter clutch assembly, copper coils in pic. Check them for wear.

    [​IMG]
    [​IMG]

    I'm basing this on last week I had my 640 in with KTM and when stripped the mechanic showed me wear on my copper coils and said there still usable one it's still charging.
    #5
  6. slackmeyer

    slackmeyer Don't mean sheeit. .

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    I'm really curious about this too. My bike does the same thing- Usually it'll turn the bike over just fine, but not start. I can kickstart the bike in two kicks, it runs great. I just took out the starter and checked it (everything fine), I've rebuilt the sprague clutch (doesn't screech, turns the bike over fine. It's a bit hard for the starter to turn the bike over, I think my auto decomp part of the cam is wearing out, but I'm loathe to spend the $160 to try a new cam. Still scratching my head, like you. I suspect electrical as well.
    And my flywheel/magneto isn't doing that (been there, done that already- and it still e-started fine while it was happening).
    #6
  7. dave186

    dave186 Been here awhile

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    I would suspect the pulser coil.
    #7
  8. bmwktmbill

    bmwktmbill Traveler

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    Guys,
    What is the function of the capacitor.
    bill
    #8
  9. Seikkailu_R

    Seikkailu_R Been here awhile

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    If pulser coil is bad there is no different between e-starter and kickin...
    #9
  10. booger1

    booger1 Long timer

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    Just throwing this out there, but I just bought a 450 and was doing the same thing, only start on kick. I found the exhaust valves where way loose. After an adjustment everything worked fine.
    #10
  11. dave186

    dave186 Been here awhile

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    Kicking it spins it over faster, and so does jump starting it.
    #11
  12. Seikkailu_R

    Seikkailu_R Been here awhile

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    Pulser coil only generate timing pulse for ignition, not actual ignition current.
    I dont know if there is any different on pulse strenght on different rpm?
    And engine starts with real slow kick when everything is ok...

    All bad pulser coils what i have encoutered are either totally gone (no connection between coil ends) or ones that still work when cold and dosnt work when hot.
    #12
  13. wrk2surf

    wrk2surf on the gas or brakes

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    the starter clutch (sprague) may be jacked up so when you pull the stator cover pull the flywheel to see..
    #13
  14. tony88

    tony88 n00b

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    After months of investigation on the same problem, also read many thread here, I found that.
    If you can kick start but cannot push start even the starter is working due to.
    1. CDI unit have voltage feed too low to spark due to current drained to starter, check voltage drop at battery if lower than 10 v during starting, this might be the case. check grounding lug from battery - to frame for loose or rusty.

    2. free-wheel FWD bearing attached to flywheel on the right side of the engine (part no. 58440026000) (no 7 in the picture) might not function well. this normally when you test HT lead with another spark plug it show some spark at the beginning and then no spark during starter is turning the engine. If this the case, change this bearing.

    I have try with 4 bikes normally the free-wheel is the case, I guess when you use electric starter this free wheel is slip.

    This should solve the problem

    Attached Files:

    #14
  15. slackmeyer

    slackmeyer Don't mean sheeit. .

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    That's the sprague clutch, it engages when the electric starter is used to spin the flywheel. It could be that the sprague is a bit too tight, and is not letting the engine run after the starter button is released. But I'm not quite sure why the kick start works fine in that case- the resistance of the sprague clutch is still there.
    #15