the solution to an overheading 640 adventure...

Discussion in 'Thumpers' started by inte, Mar 5, 2005.

  1. inte

    inte neophyte serendipity

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    ...change the IMO.

    These things are calibrated all over the map (¿or mapped all over the calibration...?)

    When I picked up my '03 640A neither the speedo nor odo was working. After a couple trips to the dealer, they couldn't figure it out. Installed a new sensor cable - no dice, then they broke down & sent me a new IMO.

    My bike was a demo bike & it turns out the shop had installed the sensor backwards at the caliper end (plus a few other missing parts, not great attention to detail on this thing...) - I flipped the sensor around & everything works fine.

    So I rode on one IMO for a while & noticed the bike temp varied greatly, and often. Would typically go up 1-2 bars at red lights & then back down nearly as quick. Often times I noticed it would hold at 3 bars on the freeway, then go up to 4 or 5 while I was on an offramp - before reaching the end of the ramp! Very sensitive. Temp warning light would come on regularly & it's not that hot here in So Cal.

    One of the buttons quit working on that IMO, so I swapped the original back in the other day & the bike goes up to 4 bars ... & stays. I put a good 50-60 commuting miles on this thing a couple days ago & never went above 4 bars. I remember trying this same old (original) unit one time last summer & I think it got up to 5 bars one time in the summer heat & the fan kicked on - stayed at 5 bars. With the 2nd unit the fan often wouldn't kick on until 6 or 7 bars - just before the dash temp light came on.

    The bike has never boiled over, there's no air in the system (checked the bleed hold near the plug), checked the thermostat in boiling water - fine, water pump & housing are pristine, flushed the rads with 60/40 Motorex/H2O (plus a couple capfuls of Water Wetter) ... all is good, & the bike runs beautifully, so I have to assume these IMO units have some "personality" built in.

    Plus, since switching the unit out my bike only has a little over 1k miles on it now ... :D
    #1
  2. jdiaz

    jdiaz .

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    Radiator cap?

    Jon
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  3. inte

    inte neophyte serendipity

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    yes. i have one.
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  4. meat popsicle

    meat popsicle Ignostic

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    dat's good. :rolleyes

    so my bike would run up to 5-6 bars lounging around town thru stopsigns and stoplights... the fan kicks in at 6 or 7? seems stoopid to kick in so late (unless there is some electrical issue i suppose). so you just have another orange IMO and that works better than the first? what about the TT IMOs? would they do the job better?
    #4
  5. inte

    inte neophyte serendipity

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    The IMO doesn't (or at least I can't see how it could) affect either the motor or when the fan kicks. The bike has always run great - I just noticed the temp display on one IMO would go up real quick, while the other didn't. I think the one I have in there now is more correct - if the other is right it would mean the 640 overheats on a California winter day. I've ridden summertime Baja without problems, so I know that's not the case...

    I can't say if another IMO would be "better" - just different. The two I have are both stock KTM parts for the '03 adventure - same part #. Perhaps it'a a quality control issue that they seem to react differently to the same motor. Were you to change out your computer it might make no difference, or you might find the fan kicks on at 5 bars every time, just because the temp gauge is rising slower.

    The definative answer would be to get a thermometer dipstick (or some other type of thermometer) & see what the actual engine temp is in relation to the number of bars on the IMO display.
    #5
  6. meat popsicle

    meat popsicle Ignostic

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    Yep, Sommer sells one of them - I would likey :D

    So I understand you now: its the IMO "reading" the temp, and you have found that to be either miscalibrated or erroneous, in that it is either not correct or it plain flails around irrespective of the temperature... dat suxs big time. thanks for the heads up inte! :thumb
    #6
  7. Jerome

    Jerome Been here awhile

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    Just in case you're considering it - the 2003 bike sensor won't work with a Touratech IMO. You have to use a TT sensor.

    The 2003 version isnt made by Touratech so has an entirely new sensor which doesnt need a magnet and just counts nuts.
    #7