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  1. #1
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    prop question 21xd ang rpms

    im running mercury 250xs right now i have a 26 trophy turning 5200 at 72mph 8 inch detweller jack plate 1 1/2 below the pad and on my 25 trophy 75mph at 5400 rpms should i go down to a 24 to get more rpms with this motor its a 2004 ser ot818946 and seems like these are all i can turn

  2. Member
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    #2
    My 21xdc with a 2004 200 efi would do 70

  3. Member
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    Sep 2011
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    Snow Hill, NC
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    #3
    Something is not right I can hit the rev limiter and be in the low 80s with a 26 trophy same setup.
    -Lance
    Bullet 21XD Mercury 250 Pro XS


  4. Member
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    Mar 2008
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    KINGSPORT, TN
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    #4
    Something is wrong somewhere.. I can run a 26 trophy around 6k rpm 3/4 below the pad.
    2005 21XD W/ 2005 MERC 250XS BULLET TOTAL PERFORMANCE BOAT!!

  5. Member
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    #5
    anything to try to hit the rev

  6. Member
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    #6
    should i take it to a shop and put on a machine to see if the fuel and rpm are right

  7. Member
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    Mar 2010
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    Selma N.C.
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    #7
    Bring the motor to 1/2"-3/4" below the pad to start and steer clear of the trophy because it will leave you hanging!

  8. Member
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    Jan 2014
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    Leesburg ohio
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    #8
    I think the xs should turn 6k at least.
    2020 Allison XB 21
    Merc 300R
    2018-SST Bullet
    Merc 300R
    Bullet 20XD
    300XS DBR

  9. Member
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    #9
    The rev limiter on that motor is 5880 rpms. You need to be at 3/4” below the pad. You should gain around 300 rpms and gain around 3-4 mph when you raise the motor to 3/4” below the pad. You also need 12”-14” of setback for the best speed, but your hole shot will be a little slower.

  10. Member
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    #10
    ok thanks

  11. Member
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    Greenville, AL
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    #11
    What lower unit and gears do you have. Correct me if I am wrong guys but doesn't he need about 12-14in set back for best results.
    2003 Bullet 21XDC with 2012 250 Mercury Sport XS
    1997 Allison 2003 with Mercury 225 Pro Max

  12. BBC SPONSOR
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    Oct 2006
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    #12
    Quote Originally Posted by Nichols View Post
    The rev limiter on that motor is 5880 rpms. You need to be at 3/4” below the pad. You should gain around 300 rpms and gain around 3-4 mph when you raise the motor to 3/4” below the pad. You also need 12”-14” of setback for the best speed, but your hole shot will be a little slower.
    This right here!!!

    Engine is too deep. Be careful with the trophy as well, they can develop hearing problems.

  13. Member
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    #13
    Where do you live in KY?
    http://www.bbcboards.net/avatars/longrodder.gif?type=sigpic&dateline=1383747738

  14. Member
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    #14
    Quote Originally Posted by Nichols View Post
    The rev limiter on that motor is 5880 rpms. You need to be at 3/4” below the pad. You should gain around 300 rpms and gain around 3-4 mph when you raise the motor to 3/4” below the pad. You also need 12”-14” of setback for the best speed, but your hole shot will be a little slower.
    All this is bang on. The 21XD has good holeshot because of the long nose. Id run 14-15" of setback if i had one. It will also make your boat easier to drive.

  15. Member stealthperf's Avatar
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    #15
    Yep ... Just like everyone is saying... 1/2 to 3/4 below the pad and you should be right in the hunt.