Checkmate conv. 270Br
#11
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X-dimension may also play a part in your handling issues. You can try spacers to drop your drive deeper in the water. Going to a 4-blade prop will definitly improve your handling. You should try a Bravo One 4-blade..
#12
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Join Date: Jul 2009
Location: Newburgh, IN/Grand Rapids, MI
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270 br
I tested a 270 BR when i was in the maket last fall and the same issue scared me away, i could not keep the porpoise out of it at slower cruise speeds. go to the Checkmate Owners Forun www.checkmate-boats.com and do some research there is a get deal of information about the cause and possible ways to control the porpoise. Great Boats i really liked the layout but chose to go a different direction. The boat i tested had the 496 HO and was running a Bravo 1 26p prop so not sure that will help. You might also contact "Mopar Crazy" on the OSO Checkmate owners forum he still owns the boat i drove, he decided to keep it and droped a 720HP Ateco engine in this spring its and absolutley beautiful boat!
Last edited by bigredbaja; 08-27-2012 at 04:46 PM.
#13
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A set of 280's will help tremendously with the infamous Checkmate porpoise.
#14
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82 predictor,
You nailed it.. It's a lot of work and very very finicky, especially when adding people.. weight, speed, etc is a new learning curve and I guess it's just not 4 me.. I wanna cruise, run WOT, or whatever w/out all the fine tuning. I can see the tabs for leveling up or possibly planning out a stern heavy boat on take off but not for preventing bounce.. I think it needs them in the V like ski's 4 more lift to hold the bow! Lol
And 2ton Chevy, yeah I've tried everything..keeping it tucked, etc.. I have to keep it tucked until I'm really upstairs and then start trimming up but when coming out of throttle I've gotta tuck it again but if it starts to bounce, there's hardly any coming out of it.. Pretty much have to stop, kill the momentum, and start over.. I've driven several boats, the 25outlaw being comparable in hull and size and nuthing like this.. I wonder if there is too much forward weight withe the mid cuddy/open bow set up
You nailed it.. It's a lot of work and very very finicky, especially when adding people.. weight, speed, etc is a new learning curve and I guess it's just not 4 me.. I wanna cruise, run WOT, or whatever w/out all the fine tuning. I can see the tabs for leveling up or possibly planning out a stern heavy boat on take off but not for preventing bounce.. I think it needs them in the V like ski's 4 more lift to hold the bow! Lol
And 2ton Chevy, yeah I've tried everything..keeping it tucked, etc.. I have to keep it tucked until I'm really upstairs and then start trimming up but when coming out of throttle I've gotta tuck it again but if it starts to bounce, there's hardly any coming out of it.. Pretty much have to stop, kill the momentum, and start over.. I've driven several boats, the 25outlaw being comparable in hull and size and nuthing like this.. I wonder if there is too much forward weight withe the mid cuddy/open bow set up
#15
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This is a characteristic of many Checkmate hulls. The bounce as you call it is caused by the hull trying to lift the bow and getting the stern up on the pad but there isn't enough speed to keep it there so it falls off and the bounce starts. It's my experience that at slower cruising speeds Checkmates require trim tabs to force the bow down and thereby stopping the porpoising before it gets a chance to get started. Trim tabs are not just for evening out loads. I've owned a 253 which eventually became the 270 and now a 300. They both required the use of tabs to not porpoise.
#16
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yeah my 2800 does the exact same thing...but a quick bump of the tabs evens her right out at any speed. at wide open i just pull the tabs up to neutral or slightly above and it turn it loose.
#17
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What many of you guys that have always had relatively bigger, heavier, offshore style boats don't realize, is that there is a fine line between the boat trying to break the friction of the water and ride up on the pad vs the water trying to suck the boat down..that's the bounce that you may be experiencing. Most of the time the bounce will occur at either moderate speeds where the hull is just trying to stay on top and plane...or at higher speeds where the hull is trying to ride up on the pad, break free and fly..At slower moderate speeds it will require tab to level out the bounce. At higher speeds the bounce should dissappear (assuming you have enough motor and speed to get past the bounce) and should not require any tab. In the small high performace boat world (16'-21') it's pretty easy to accomplish..usually around the 65-75mph mark the boats begin to fly and level out..
#18
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Update: after my worst ever boat ride in history @ the lake Cumberland poker run I was able to get my hands on a 24 p 4 blade to try this morning. It and a "whale tail" allowed my boat to handle like a boat @ all rpm ranges w/2 people. Now I've gotta load down the coolers and p/up some fat chix and see how it does.. Thanks 4 all the replies