KTM LC4 (640) Thread Index

Discussion in 'Thumpers' started by meat popsicle, Jul 9, 2005.

  1. Diddly

    Diddly Bored of Directors

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    @B.Ross
    @atomizer


    Looking for electrical input / advice.

    I’m on a trip with a 2006 Adventure (w/ SMC rear).

    Early afternoon, the bike blew the 20 amp main fuse - no power anywhere on the bike. We replaced the fuse and made it a few more miles before we stopped for a break. We went to start the bike and the battery was almost dead. The bike would turn over slowly but not start and we eventually drained the battery. It would also not start by Kickstarter.

    We pulled the seat and tank and started visually inspecting for bare wires. The bike had several electrical accessories we started pulling to eliminate guesswork: two GPS wiring harnesses, USB double charger, Oxford grips power loom (left grips mounted) and second radiator fan power. One set of these power supplies had bare wires and we had hoped this would be the source of problems.

    We put in a fresh battery and only wired the main bike leads. The starter would turn over but the bike wouldn’t start. - Here’s the real kicker, anytime you let off the starter one spark would arc off the upper right hand subframe-to-frame bolt (see pic for location). We’re still figuring out this bike. We haven’t found any additional bare wires.

    The frame/ sub-frame are isolated by rubber bushings. We’re thinking there should have been(?) a grounding strap between the two but we can’t find one. Anyone know if the frames would have been grounded on a 2006 ADV?

    What else should we be checking? We are done for the night and haven’t found where the main ground is located. Wiring diagram makes it look like there could be five grounds and we are yet to find any but the battery ground strap.

    All help appreciated!

    IMG_5225.JPG
  2. Diddly

    Diddly Bored of Directors

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    We found the main(?) ground near the CDI. Removed, cleaned and reattached.

    We’ve cut zip ties from about all wire harness at rear of the bike, no worn or bare wires. Pulled wires away from frame and tried hitting starter, still seeing the spark at the frame to sub-frame bolt.

    Moving to inspect wires at front now.
  3. Whodatschrome

    Whodatschrome Long timer

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    Maybe back out the subframe bolts about halfway, then retighten them? Perhaps there's enough corrosion in between the threads that the subframe isn't getting a good enough ground?

    And I've only seen bad wires under the dash, never in the rear portion of the bike yet.
    Diddly likes this.
  4. timeOday

    timeOday Long timer

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    I've had shorts on the right side near the back of the seat under the bodywork, and also inside a turn signal that had been damaged or vibrated loose inside (I forget).

    But the spark at the frame-to-subframe bolt seems like it shouldn't happen if both are on a common ground. Is the grounding supposed to rely on conductivity through the frame-to-subframe attachment - not a wire that clamps to both? Also arcing seems like too high voltage to just be the normal accessory wiring shorts?
    Diddly likes this.
  5. Diddly

    Diddly Bored of Directors

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    Worth a shot and easy. More comment coming in a sec below...
  6. Diddly

    Diddly Bored of Directors

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    I think you’re on the right path!!

    We’ve been thinking on how the starter is turning over but the bike has never fired. We pulled the plug wire which inadvertently separated the wire from the plug socket / plug connector. (I’ve only had experience with automotive plug wires where the socket was one piece with the wire.) This plug wire and plug connector (socket) are meant to be two pieces. The connector has a threaded screw which screws into / makes contact with plug wire. Interesting, and makes for easy field repairs. - We re-screwed the connector to the wire, put a spare plug in the connector, held the plug to the frame (ground) and hit the starter button. Some good news, we the plug was getting spark - and no more spark at the sub-frame bolt! We returned plug wire to plug in the bike and tried to start it. Bike wouldn’t start still. We made sure carb bow was full (tank off bike) and even tried starting fluid. Bike won’t start. We’re thinking the spark looked weak / given it wouldn’t even stumble on ether we have someone on their way here with a new coil.

    The sun is just peaking over the Kentucky hills and forecast for 95 F today. Cross your collective fingers!!
    Whodatschrome likes this.
  7. Whodatschrome

    Whodatschrome Long timer

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    I’ve had a corroded sparkplug wire to cap connection before on my 525. I still had spark, but my bike ran like crap. For a temporary fix, I cut about a 1/2” off of my spark plug wire then screws the cap back on. It made the bike run well again. I then ordered a new cap and wire, and installed them when they arrived.
  8. meat popsicle

    meat popsicle Ignostic

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    Did anyone recommend Hondabond yet?
  9. meat popsicle

    meat popsicle Ignostic

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    JB Weld?
  10. Diddly

    Diddly Bored of Directors

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    She’s running!!

    Replacing the coil worked. Not sure how that was causing arcing at the frame...

    We removed lots of unused power accessories, found a small air leak at the intake boot, found the electric isolator coating had been rubbed through the bottom of the condensator.

    Packing back up. We have miles to make up on a 1000 mile tour.

    Thanks!
    Whodatschrome and timeOday like this.
  11. skibum69

    skibum69 slave to gravity Super Supporter

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    There is a big ground strap on mine to the main frame.
    Diddly likes this.
  12. Irongig

    Irongig Been here awhile

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    Hondabond, yamabond, 1211, and so on, read all the thread about resealing the rocker cover, too many guys had leakage after the work.
    At the end, i took it to a mechanic to have the work done.
    Figured out that having just bought it, better have a general inspection made by someone Who does this ad job and have peace of mind on a mateinance that hopefully will give me 30 k kms trouble free
    enduro0125 likes this.
  13. supermoto690

    supermoto690 Been here awhile

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    Hello guys, I was in a accident yesterday a lady cut me off and I smashed into her car, the only thing that broke is that little bleeder on the fork that you press to get the air out.Now its gonna take maybe few months until I get my insurance money is there a way to block that hole because air and oil is whizzing trough it as I compress the forks?

    Attached Files:

  14. taraba

    taraba Adventurer

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  15. supermoto690

    supermoto690 Been here awhile

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  16. atomizer

    atomizer Be here now

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    Just saw this. Was on the COBDR...
    glad you got it figured out and happy the bike is still charging along.
    Cheers
    Diddly likes this.
  17. supermoto690

    supermoto690 Been here awhile

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    I need help with my handlebars, I just did my first small ride after the crash to see if everything is ok. I tought the handlebar was bent so I put on a new one and same thing. Something is not aligned in the upper triple clamp. What do I need to do to straighen it?

    Attached Files:

  18. Diddly

    Diddly Bored of Directors

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    I don’t know about the triple clamps, but the handlebar mount looks twisted. Take the bar off and see if the lower bar mount (one-piece) is bent. If it looks good, look to see if the lower bar mount shifted on the top triple clamp. Loosen bolts and shift it back.

    If the bar mount is twisted, I wouldn’t try to bend it back. Aluminum likes to crack. You wouldn’t want your bars to break off at speed..

    Look for new bar mount upgrades (upper and lower clamps) at Highway Dirt Bikes / other. Gives you a good chance to upgrade hand guards to stronger overall setup.
  19. enduro0125

    enduro0125 Sticks and Stones™..

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    Hold the front tire between your knees and give the bars a good tug in the direction they need to turn to straighten.

    A solid object to bang the tire against work too
    Like a rock or a tree

    They are rubber mounted and tend to twist in a fall
  20. shrunken

    shrunken Adventurer

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    I would take the risers off to inspect them, then try and put everything back together straight. I just replaced the rubber bushings in mine and notice the aluminum riser have quite a loose fit after years of vibrating.