double stack trailer

I am getting ready to convert my trailex trailer to a double stack. Looking at images they all seem to have the rear upper rear crossbar noticeably higher than the front. Anyone know why they do this? I had planned on keeping the crossbars low and fairly level, but don't want to overlook something before I start cutting the uprights. Below is an example. Thanks

http://www.cathouse1.com/Misc%20pix/clip_image008.jpg

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Pete Knapp
Schodack landing,NY
Goodall Viper,AHPC Viper,Nacra I20
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It's because of the rocker in the hills. As you slide the boat in over the rear cradles you need the extra clearance from the bottom of the hull to the top of the deck.

Be careful about overloading a Trailex trailer, I've seen a lot of bent ones from carrying 2 x N20's, or 1 x N20 and 1 x F18.
Thanks for the reply. I was thinking there needed to be a little extra room, but maybe I underestimated it.
Mine will carry an I20 and F16 on top. Where is the weak point that the trailex's are bending?

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Pete Knapp
Schodack landing,NY
Goodall Viper,AHPC Viper,Nacra I20
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It's the fore/aft beams that bend. If you look from the side, the high spot will be over the axle/springs and the front and back will droop down. I've seen more than one break the center beam. The only way to bulletproof it is to double up the center and fore/aft beams.
Many years ago, we had double stacked tandem Nacras from Texas to Florida and back. I just flipped the top boat over and placed foam cushions overlapping the beams. Keeping the aft beams low kept the forward trailered mast sections high enough to clear a Suburban. Worked very well.

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Scott

Prindle Fleet 2
TCDYC

Prindle 18-2 Mod "FrankenKitty"
Tornado Classic "Fast Furniture"
Prindle 19 "Mr. Wiggly"
Nacra 5.8 "De ja vu"
Nacra 5.0
Nacra 5.8
Tornadoes (Reg White)
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Turns out that the rocker in the hulls is minimum. The I20 has a fixed self tacking jib track that requires the rear
cross bar to be quite a bit higher.

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Pete Knapp
Schodack landing,NY
Goodall Viper,AHPC Viper,Nacra I20
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