25 Yamaha 2 stroke is not hitting max rpm.

Discussion in 'Outboard Maintenance' started by Les_Lammers, Aug 9, 2012.

  1. Les_Lammers

    Les_Lammers Well-Known Member

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    I have a 2010 Yammy 25 2 smoke with a Power Tech SRA 4 10" 10 pitch prop on a 14' catamaran hull that at WOT is at
    4500 RPM's on a Tiny Tach. I thought it may be the prop but a thread below has me thinking it may be a fuel line issue. The motor has about 15-20 hours on it so it is essentially new. Thoughts?
     
  2. cutrunner

    cutrunner Cert. Yamaha technician

    Im thinkin prop.
    Whats the hull weigh?
    Pics of hull?
     

  3. Les_Lammers

    Les_Lammers Well-Known Member

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    It's a 14' Livingston catamaran hull 320lbs.

    [​IMG]

    Not a great pic but it will have to do. Big Black Drum in the Glades.
     
  4. AfterHours2

    AfterHours2 Stripper in my own Mind!

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    What type of speed #'s are you getting? Reason I ask is because I run the same exact motor and prop and have no issues with rpm's or top speed. Someone already did the research before I bought the rig though..
     
  5. cutrunner

    cutrunner Cert. Yamaha technician

    Do u still got the stock prop? If so, throw that on there and see what it does.
     
  6. Les_Lammers

    Les_Lammers Well-Known Member

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    I put the stock prop back on and will post after I wet it.

    Cutrunner, perhaps this thread should be moved to the prop shop?
     
  7. cutrunner

    cutrunner Cert. Yamaha technician

    Eh, we'll see soon enough lol
     
  8. Sheremeta

    Sheremeta Well-Known Member

    Engine could be fine and the tiny tach may be off.
     
  9. Les_Lammers

    Les_Lammers Well-Known Member

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    With the stock 9 7/8 x 11 prop I hit 5200 rpm per the TT so I am sure it's the prop. It it looks like a Power Tech SRA3
    10 x 9 or 10 x 10 is where I need to go. What to you guys think?
     
  10. Les_Lammers

    Les_Lammers Well-Known Member

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    I was getting 18 -20 with the 4 blade and 22.5 with the stock prop with CMC TnT and a SE 200 fin.
     
  11. Les_Lammers

    Les_Lammers Well-Known Member

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    I have a 10 x 9 SRA3 on the way.