"new" 640 Adventure - stock exhaust?

Discussion in 'Thumpers' started by prossett, Mar 9, 2014.

  1. prossett

    prossett Adventurer

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    Just got a 2004 KTM 640 Adventure!!! :evil

    Trying to figure out what the previous owner has done.

    Is this a stock exhaust?

    [​IMG]
    #1
  2. Hipster

    Hipster Long timer

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    That looks like the stock Supertrap can.
    #2
  3. prossett

    prossett Adventurer

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    OK, thanks.

    The second owner was 99% street, and so didn't ride much - like riding a jack-hammer!!! LOL - but the first owner put in some mods.

    So far, I've found: Touratech skid plate, Scotts steering damper, both lights wired together, net on air filter side box + top snorkel replaced with another net, removed thermostat and emissions stuff (new in box with other spares LOL), wider footpegs, an oil temp gauge screwed into left side engine, and...?

    Bike has 13,000km, is in UAE, and looks to be in great shape - like this:

    [​IMG]

    [​IMG]
    #3
  4. bmwktmbill

    bmwktmbill Traveler

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    #4
  5. docwyte

    docwyte Long timer

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    Derek from Motolab told me that with an opened airbox and the stock exhaust the motor can run very lean. He strongly suggested upgrading the exhaust to either a Leo Vince or an Akrapovic. Or closing off the airbox.
    #5
  6. prossett

    prossett Adventurer

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    Good advice guys, thanks.

    I've also wondered why the previous owner would open up the air intake so much and then run a stock exhaust. Maybe he swapped back the stock part before selling it? Or maybe he cored out the stock exhaust? It's loud, but I don't have another 640 anywhere near that I can compare with, and youtube doesn't really cut it.

    Let me shine a light into that can and see if there's signs of stripping stuff out.

    Also, I'm not running lean, so there must be a mega-jet in the carb. This weekend I'll have it out and see what the jet size is. I'll also post photos of the net up top the air box, as it looks like a home-made jobbie. The side one is a metal plate with KTM stamp and a metal mesh square for the air to go in (but it's then covered by the plastic cover, so it's not totally exposed to vacuuming in sand).

    EDIT: actually, found it online - side air box lookalike this: [​IMG]
    #6
  7. clintnz

    clintnz Trans-Global Chook Chaser

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    They're not very loud stock, so chances are the can's been gutted.

    That is the std KTM accessory vented airbox lid.

    Looks like a good rig. Another nice little upgrade you have there is the proper chain guide ahead of the back sprocket. The stock plastic fin can be a bastard for feeding your chain off if you drop into a narrow rut or nudge a rock.

    I didn't think the Adv's got the twin front discs until 05 model year but I could be wrong on that.

    Cheers
    Clint
    #7
  8. gunnerbuck

    gunnerbuck Island Hopper

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    04 was the year they changed to the 950 front end... After having issues with the original 03 front wheel KTM decided to do a change in a big way...
    #8
  9. wrk2surf

    wrk2surf on the gas or brakes

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    remember this is to be used WITH the black outside sidecover on the airbox..
    #9
  10. Kawidad

    Kawidad Long timer

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    I would suggest when you pop open the carb to have a look-see, you check the internal parts for wear. With that way opened up airbox and living in a sandy environment, that is a recipe for nasty carb problems. :deal
    #10
  11. bmwktmbill

    bmwktmbill Traveler

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    My guess...
    He gutted the muff and applied the side screen mod which was first first worked out on the dyno by Sommer KTM in Germany/Austria, they were like a back door to the factory.

    All this info is buried in old threads, hashed and rehashed. My guess is he chickened out because of the sand issue so closed it and tossed the snorkle instead to accomplish the same thing(maybe).

    Sommer also recommended a jetting change I think and I believe it was for the Hi flo heads that they did the dyno work. Some suggested that Sommer did the side door because of German enviro laws so they were scared to touch the snorkle, others disagree about all this. All this was about the BST40carb.

    Anyway check to see if you still have the collector box in the exhaust system or if the PO replaced it with the comp mod collector box eliminator pipe?

    As for jetting, some have suggested there is a direct connection between penis length and main jet size.

    BTW, glad to have you on a KTM and for caring, welcome.

    I didn't reread this but you might be interested.

    http://www.advrider.com/forums/showthread.php?t=123569&highlight=Sommer+mods



    bill
    #11
  12. prossett

    prossett Adventurer

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    I think we're getting somewhere - very knowledgeable forum, guys :ear

    In fact, the side air box is covered by two parts: the solid black plastic side, and under it is the metal net, the KTM Racing part. It is not directly exposed.

    Here's with the seat and side air-box plastic cover removed:

    [​IMG]

    Here's the top of the air box, where the snorkel used to go (snorkel is in the parts box I received with the bike, so I could put it back - but I want to understand this further before making any changes: it runs like a beast! 8)

    [​IMG]

    As for the exhaust muffler, more clues of it not being stock: there's a hanger on it that doesn't fit the bike. Maybe stock SuperTrapps all have this hanger as it was used on other models, and the 640 Adventure engineers were happy to just leave it unbolted there?

    See top left:

    [​IMG]

    Thanks for the welcome, guys 8)
    #12
  13. bmwktmbill

    bmwktmbill Traveler

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    Does running like a beast mean it is running good or bad?
    bill
    #13
  14. prossett

    prossett Adventurer

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    LOL Good, man - it runs great! Can't tell if it can do better, but as is I'm plenty happy. Truly a great bike, even given the harsh vibes on tarmac.

    I had a bad day yesterday, though, learning again the life lesson of "if it ain't broke, don't fix it!" LOL and I'm 46 so I've had plenty of time to learn that.... :(

    But I must send my apologies to the good citizens of the great country of Austria, coz I might have cussed at you repeatedly while wrenching :lol3

    Anyhow, I've determined the exhaust was re-packed and it's stamped KTM. I've also decided I'll wait for when maintenance is actually needed to pull stuff off - much better to just ride the beast 8)
    #14
  15. docwyte

    docwyte Long timer

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    I installed Highway Dirt bikes hand guards, anti vibe inserts and bar end weights. They dramatically helped with the vibrations through the bars...
    #15
  16. wvrocks

    wvrocks Been here awhile

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    Looks like you are missing the lower exhaust hanger

    EU/AUS models
    Upper Hanger Fiche #19 SILENCER BRACKET CPL. 2001 58405085044
    Lower Hanger Fiche #22 SILENCER BRACKET CPL. SHORT'96 58305165244

    US Models With Supertrapp Exhaust
    Upper Hanger Fiche #19 SILENCER BRACKET CPL. SHORT 58305165144
    Lower Hanger Fiche #22 SILENCER BRACKET CPL. SHORT'96 58305165244

    [​IMG]
    http://www.ktmpartshouse.com/fiche_section_detail.asp?section=465786&category=Motorcycles&make=KTM&year=2003&fveh=10988
    #16
  17. prossett

    prossett Adventurer

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    Yes, exactly right. I have no central hanger, and the front one was just hanging there. Someone put the muffler on in a hurry.

    The anti-vibe inserts look excellent! I'll see how I get on with the first longish trip, but I have a feeling it'll be inserts, sheepskins, gel pads, and all sorts! LOL

    I've ordered crash bars for the tank and a headlight grille - metal mesh: old skool 8) from Holan.pl

    Today was stupid day - it rained overnight and starter button doesn't fire. No noise at all: I check battery, fuse, of course the kill switch - hah!, and then figuring it's either ignition key or the starter switch, I open up the switch. I give the contacts a good clean which was badly needed, still nothing.

    It was in gear...

    Anyhow, it needed cleaning, and now I know how it goes together :freaky

    [​IMG]
    #17
  18. gjcourt

    gjcourt n00b

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    So another newbie here. I've been lookin' 'round for one of these air box covers with the perf metal. I believe this product is now discontinued (not surprising seeing as it came out, oh idk, maybe 10 years ago???). Are there any places that still have some stock of these ktm racing covers, or another shop that's putting out an equivalent?

    I know Creeper made his own

    And I remember seeing on one of the forums a part # that one of the all-mighty's put up for he racing cover, but a quick internet search turned up empty (including a quick poke around evil bay).

    Is the name of the game that it's too late to pick one of these up and I'll have to fab one out of something?

    Thanks for the help!
    Gus
    #18
  19. prossett

    prossett Adventurer

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    If you can cut sheet metal, it's easy to make. There's a top fold that you'll need to factor in, which hooks the cover in place without bolts. And then there's the mesh that will need to be glued into place, or tack welded. And then bolt holes drilled lined up to match the plastic cover. If you want dimensions just ask.

    In other news, a parcel arrived today...

    for me???

    from Poland??

    sent by Holan for Motorcycling Adventure?

    Whatever could it be...? :evil

    [​IMG]

    (stupid dog not included in parcel, and not involved in delivery either)
    #19
  20. Seikkailu_R

    Seikkailu_R Been here awhile

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    Looks like a stock HGS-4 exhaust, same as HGS-3, except that removable end cap, witch is purely cosmetic.

    Most later LC4 models only use two mounting points for silencer, fixed one on front and band on rear, even if there is brackets for that middle mounting on silencer and on subframe.
    #20