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Thread: 650 Dakar valve results help needed

  1. #1
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    650 Dakar valve results help needed

    Okay, for peace of mind I did a valve check on my 07 Dakar.
    As mentioned it has about 9200 miles on it (I miss - typed 7500 on my last thread)

    Anyway, my feelers go in .02mm increments.

    Here are the results:

    Exhaust - .30mm would not go in either one, .28mm slid in fairly easy..so both were .29mm
    Intake - .10mm would not go in either one, .08 slid in easy on both so they would both be about .09mm

    Now...on the bike spec sheet (under the seat) they say exhaust range is .25mm to .30mm, intake .10mm to .15mm
    This would mean my intake is too tight, exhaust is at the high end..better than too tight I guess.
    However...on F650.com they listed new tolerances as per a BMW spec sheet as follows:
    Exhaust - .25mm to .33mm
    Intake - .03mm to .11mm

    This is the first time I have ever done this so be gentle..I have questions:
    1. which set of specs is correct?
    2. do the valves slowly start to get tighter as mileage increases?
    3. I am not good enough (or confident)to do a shim under bucket type swap, are my valves okay as they are?

    Thanks for any and all help
    War is when the government tells you who the bad guy is. Revolution is when you decide that for yourself. ÔÇôAuthor unknown

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    Benchwrenching PGlaves's Avatar
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    Paul Glaves - "Big Bend", Texas U.S.A
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    Quote Originally Posted by PGlaves View Post
    Yes
    I think I understand..maybe
    War is when the government tells you who the bad guy is. Revolution is when you decide that for yourself. ÔÇôAuthor unknown

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    Benchwrenching PGlaves's Avatar
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    Quote Originally Posted by manybikes View Post
    I think I understand..maybe
    I consider them in spec. Exhausts are clearly within both/either spec quoted. It would be nice to see the intakes a hair looser, but intakes never burn unless they totally fail to close. As long as it is breathing well and running well I wouldn't pull the cams and change them.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

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    Quote Originally Posted by PGlaves View Post
    I consider them in spec. Exhausts are clearly within both/either spec quoted. It would be nice to see the intakes a hair looser, but intakes never burn unless they totally fail to close. As long as it is breathing well and running well I wouldn't pull the cams and change them.
    Thanks, should be good for another 6k.
    Another thing, 10 nm for the valve cover bolts...just does not seem right.
    10 nm is not much more than finger tight. Anyway, I just lightly snugged them up but I will be watching closely to see if I get any oil leaks.

    Better on the cautious side, I have read on other forums the consequence of over tightening those...very expensive mistake.
    War is when the government tells you who the bad guy is. Revolution is when you decide that for yourself. ÔÇôAuthor unknown

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    Benchwrenching PGlaves's Avatar
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    Quote Originally Posted by manybikes View Post
    Thanks, should be good for another 6k.
    Another thing, 10 nm for the valve cover bolts...just does not seem right.
    10 nm is not much more than finger tight. Anyway, I just lightly snugged them up but I will be watching closely to see if I get any oil leaks.

    Better on the cautious side, I have read on other forums the consequence of over tightening those...very expensive mistake.
    They are "shoulder" bolts. That is they go in so far and only that far before the shoulder hits the head. Further tightening only stresses the thread section - it will not and cannot further compress the gasket. They only need to be tight enough to keep themselves in place. If screwed in until the shoulder is against the head any leaks are caused by an old inelastic gasket or debris where the gasket seals.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

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    Quote Originally Posted by PGlaves View Post
    They are "shoulder" bolts. That is they go in so far and only that far before the shoulder hits the head. Further tightening only stresses the thread section - it will not and cannot further compress the gasket. They only need to be tight enough to keep themselves in place. If screwed in until the shoulder is against the head any leaks are caused by an old inelastic gasket or debris where the gasket seals.
    No oil leaks...good to go. Thanks for your help PGlaves.
    War is when the government tells you who the bad guy is. Revolution is when you decide that for yourself. ÔÇôAuthor unknown

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