Primary chain adjustment - confusion

Discussion in 'Transmission' started by dangerdan, May 23, 2009.

  1. dangerdan

    dangerdan Junior Member

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    I got this info from this site

    Open the primary chain inspection cover and check the chain. The chain adjuster hangs in the open below the primary for easy access. "It takes a 7/8-inch open-end wrench," and a 1/4 Allen and should be adjusted hot." The new Sportster manual called for 3/8 to 1/2 -inch cold and 1/4 to 3/8 inch slack while hot

    My manual calls for 5/8 to 7/8 -inch cold and 3/8to 5/8 inch slack while hot

    Metal expands when hot and contracts when cold, so I would think these measurements would be reversed.

    :17::17::17:


    Is my logic flawed or is this a mistake ?
     
  2. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

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    always best to do adjustments when cold
    but the clutch drum and compensator are the bits with the most expansion making the chain tighter when hot cold settings take account of this expansion

    Brian
     
  3. dangerdan

    dangerdan Junior Member

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    That makes sense.

    Thanks for the quick response.

    I'm going to recheck my measurements and hopefully I will be riding tomorrow:D:D:D
     
  4. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

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    if the weather works well here ill be riding in the morning also
    have a good one

    Brian
     
  5. robermv32

    robermv32 Active Member

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    I have a 2008 Softail Custom and it has the "automatic primary adjustment" No, inspection cover. Just how does this work ? Is it something that has to be done at the dealers ? How would you even check it without taking off the entire case ?

    Any help will be appreciated
     
  6. glider

    glider Veteran Member

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  7. rancid

    rancid Active Member

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    id do the adjustment when hot as thats when the primary chain is doin its work, and it will most certainly get tighter as it gets hot, if you do it when its cold it may be overtightened when hot, if you do it hot you can be sure it wont be too tight.
     
  8. glider

    glider Veteran Member

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    And if you do it when hot, the tolerances that you use for a cold engine will give you excessive whipsaw in the chain when hot.:s
     
  9. chopit

    chopit Member

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    thanks for the help