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 Question about rpm's 
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Location: SW Michigan
Post Question about rpm's
I have a go devil with a 25 hp Kohler. It's mounted on a 14x70 landau flat bottom. From what the shop said I should be running about 3700 r's at top end. My question is I can get those r's out of the engine but only with me and the dog with decoys in the boat.

If I add another dude I'm lucking to rev 3400 r's. Is there anything I can do to get my rpm's up, or is it just one of those things I've got to put up with? I can seem to make the r's go up and down by pushing on the handle to decrease the angle of attack but not to 3700. Should I mess with the govener or just keep it where it's at? It's on the last available hole. IE max r's. It's not that bad but i'm always looking for MORE SPEED!
thanks
Smoke

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Wed Jan 28, 2009 9:05 am
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Post Re: Question about rpm's
What rpm ya turnin out of the water? If you are only turning 3800ish out you aint gonna come close in the water! I turn close to 4200 out of water and get 3900ish in witha good prop! You should be turnin more with a worn prop! I believe to get more rpms ya gotta adjust the screw (well its actually a bolt with a nut on it) in the back of the linkage in addition to the spring!


Wed Jan 28, 2009 4:04 pm
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Post Re: Question about rpm's
Thanks I'll look it over and try it. I'm not sure of the rpms it turns out of the water. Around 4000 I believe, but I will check as soon as the weather breaks here. We've gotten about 130" of snow so far this winter. The boat is covered up with snow as well as the motor. We should be able to dig out about March!
Smoke

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Quote classic by rangerp: "Red seemed to be enjoying herself, and I assume by the look on her face was about to hit the high-note and throw a locate as she treed the possum."


Thu Jan 29, 2009 6:16 am
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Post Re: Question about rpm's
Yeah let us know! We got almost 2 inches of snow the other day!


Thu Jan 29, 2009 4:21 pm
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Post Re: Question about rpm's
If its any help...

I ran all season with a new 9x6 and using a gps got 21 mph by lifting up on the handle and sinking the prop as deep as possible... This told me that I was under pitched... Well by the end of the season - speed was down to 19 mph with prop as deep into the water as possible and 18 mph if I allowed it to choose it's own depth....

Got a new 9x7 GoDevil Prop at the end of the season - rpms are a bit lower when allowing the tail to find it's own depth - but pushing 20 mph and by pressing down on the handle and causing the prop to surface just slightly it is now hitting 23.2 to 23.5 mph in deep water...

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Thu Jan 29, 2009 10:04 pm
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Post Re: Question about rpm's

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Blackwater Marine LLC.


Quote classic by rangerp: "Red seemed to be enjoying herself, and I assume by the look on her face was about to hit the high-note and throw a locate as she treed the possum."


Fri Jan 30, 2009 9:05 am
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Post Re: Question about rpm's
Need a GPS to be sure...

Speeds increase when prop is run deeper - under

Speeds increase when prop is run surfacing - just right or over

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Fri Jan 30, 2009 11:38 am
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