# 25 Yamaha 2 stroke is not hitting max rpm.



## Les_Lammers (Feb 17, 2007)

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?


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## cutrunner (Jun 8, 2010)

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


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## Les_Lammers (Feb 17, 2007)

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










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


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## AfterHours2 (Aug 2, 2010)

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..


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## cutrunner (Jun 8, 2010)

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


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## Les_Lammers (Feb 17, 2007)

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?


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## cutrunner (Jun 8, 2010)

Eh, we'll see soon enough lol


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## Sheremeta (Nov 29, 2010)

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


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## Les_Lammers (Feb 17, 2007)

> Eh, we'll see soon enough lol


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?


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## Les_Lammers (Feb 17, 2007)

> 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..


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


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## Les_Lammers (Feb 17, 2007)

I have a 10 x 9 SRA3 on the way.


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