- Location
- Hudson River Valley
All: I've quite happily read these forums on the above, and want to toss in my bit, hopefully helping someone else.
I bought a Superjet about 10 years ago. When it was new, with the stock useless intake grate, aluminum prop and stock ride plate, it would go real fast if it hooked up, but it didn't hook up too much in the chop of the Hudson River. I was coming off a 440 so I was totally blown away by the SJ.
I installed a Riva TriLoader, Skat Trak prop, and a Jet Dynamics ride plate. The ski would porpoise a lot at speed. Since I ride a lot alone, I really didn't have much to compare to, and I thought that it was a fact of life or my riding style or my weight. In rough water it hooked up well, and since most of my riding is chop and rolling waves, I was able to work around it-I'm not much of a flat water guy. If things were flat, I'd not go out...living right on the river, I can choose my days, kinda like the snow ski guys who only go out on powder days.
Now, I do a yearly freeride trip to Florida. Our first day is flat water, with a buoy course for shakedown and fast riding. I noticed for the first time my friend's two SJ's were not jumping up and down, and to my shock, I could ride his skis flat out with the nose down. Back on my ski, it was back to the up and down up and down. It wasn't me, it WAS the ski. My friend's ski had a two scoop intake grate and a slightly longer plate.
The next year, we rode with the Mauler. He had heard of my plight, and set me up with a Worx extended plate (aka "the cookie sheet"), and tossed some washers in the front of the Riva intake grate, putting it down below the hull another eighth of an inch.
What a difference ! I instantly went from bouncing to a ski that felt as if it was being towed via an undersea cable. It was suddenly dead flat at full speed-for the first time I saw the full 45 mph or so steady. Now, I couldn't keep up with Mauler in a buoy course (as if !), but it was a lot easier to turn, as I was not unhooking all the time. The engine has cleaned up ports (superjet guys, match the liners and ports) and a milled head, but is otherwise stock, stock pipe, primer kit.
The next day we rode in the surf...I felt that it was a bit nose heavy compared to my usual rough water riding, but I was so happy that I could hook up and go on the flats I didn't change things, besides surf was such that I wasn't getting picky...I was getting massive air time on some big stuff.
Back home on the Hudson, I was suddenly disappointed. I could not get the nose up. With the small 3-5 foot curls, I didn't jump...rather the ski cut over the back of the waves. The nose stayed down. I realized that I was perfectly set up for buoys and flat water.......but that I'd gone too far for freeride-the ski was perfectly stable but less fun to ride. That undersea cable didn't stretch at all.
Over winter break, I made some other mods. The long Worx ride plate was cut back to the "standard" worx plate length. (I bent it-my bad) I took the washers out of the intake grate, and went out. With the shorter ride plate, the nose came up again, but there was still a porpoise issue, as the ski went back to hook up/loose/hookup. When hooked up, the Worx grate aimed the hull at the right angle, so the hull was usually angled on the water the right way, but the on/off nature of the hookup was still annoying, and I now knew this could be fixed, having ridden other skis, but how ?
I stared for a long time at pictures of intake grates, and realized that the early TriLoader grate was an extreme 'deep scoop' design. Moreso, it looked as if time had marched on, and the current deep scoops had notches cut from the back of the plate, and mostly smaller scoops, unlike the Riva.....suddenly the light bulb went on.
A Worx 205 intake grate, the smaller one, was installed, and I wished I'd done it years ago. The problem was not with the ride plates.....it was my super duper deep scoop grate causing the problems. I note that none of the current grates looks like this, so I ended up with an evolutionary dead end but due to my lack of other standup guys to play with, never knew.
The Riva grate pulled the entire hull down hard. While it filled the pump, the tradeoff was that the "pull down" was so strong that when it unhooked, the hull would then bounce upwards, until the suction then caught again, pulling the hull down. The Worx grate filled the pump 90 % as well as the Riva, but the Worx grate didn't suck the hull down, and this allowed the hull to work. Suddenly, turning was much, much easier and I could angle the hull almost like my old 440!!!! The Riva grate didn't tolerate much angle, but the Worx allowed me to go way over before the "unhook". High speeds didn't result in the porpoise, and I no longer had to worry about perfect throttle at speed, as the Riva would stop the ski instantly off throttle with handlepole in gut (ow).
In short, this grate pulled the ski down way too hard, was unhappy at angles while turning, and while it did fill the pump in rough water, caused endless porpoising.
So, it comes down to angle..your ride plate determines hull *angle*.
It comes down to suction....your intake grate pulls the *whole hull* down.
A deep scoop pulls the hull down harder than a smaller scoop. I had a worst case scenario with an early design which pulled down way too much at speed, causing porpoising and loss of turning ability.
I feel like it's a new ski.....and the biggest change was dumping the Riva Triloader grate and bolting in the Worx. I think there is too much emphasis on the ride plate, and not enough on the intake grate.
I learned you can overdo both the intake grate and the ride plate. An intake grate does not just fill the pump, it also serves to increase the weight of the hull as expressed on the water.
I bought a Superjet about 10 years ago. When it was new, with the stock useless intake grate, aluminum prop and stock ride plate, it would go real fast if it hooked up, but it didn't hook up too much in the chop of the Hudson River. I was coming off a 440 so I was totally blown away by the SJ.
I installed a Riva TriLoader, Skat Trak prop, and a Jet Dynamics ride plate. The ski would porpoise a lot at speed. Since I ride a lot alone, I really didn't have much to compare to, and I thought that it was a fact of life or my riding style or my weight. In rough water it hooked up well, and since most of my riding is chop and rolling waves, I was able to work around it-I'm not much of a flat water guy. If things were flat, I'd not go out...living right on the river, I can choose my days, kinda like the snow ski guys who only go out on powder days.
Now, I do a yearly freeride trip to Florida. Our first day is flat water, with a buoy course for shakedown and fast riding. I noticed for the first time my friend's two SJ's were not jumping up and down, and to my shock, I could ride his skis flat out with the nose down. Back on my ski, it was back to the up and down up and down. It wasn't me, it WAS the ski. My friend's ski had a two scoop intake grate and a slightly longer plate.
The next year, we rode with the Mauler. He had heard of my plight, and set me up with a Worx extended plate (aka "the cookie sheet"), and tossed some washers in the front of the Riva intake grate, putting it down below the hull another eighth of an inch.
What a difference ! I instantly went from bouncing to a ski that felt as if it was being towed via an undersea cable. It was suddenly dead flat at full speed-for the first time I saw the full 45 mph or so steady. Now, I couldn't keep up with Mauler in a buoy course (as if !), but it was a lot easier to turn, as I was not unhooking all the time. The engine has cleaned up ports (superjet guys, match the liners and ports) and a milled head, but is otherwise stock, stock pipe, primer kit.
The next day we rode in the surf...I felt that it was a bit nose heavy compared to my usual rough water riding, but I was so happy that I could hook up and go on the flats I didn't change things, besides surf was such that I wasn't getting picky...I was getting massive air time on some big stuff.
Back home on the Hudson, I was suddenly disappointed. I could not get the nose up. With the small 3-5 foot curls, I didn't jump...rather the ski cut over the back of the waves. The nose stayed down. I realized that I was perfectly set up for buoys and flat water.......but that I'd gone too far for freeride-the ski was perfectly stable but less fun to ride. That undersea cable didn't stretch at all.
Over winter break, I made some other mods. The long Worx ride plate was cut back to the "standard" worx plate length. (I bent it-my bad) I took the washers out of the intake grate, and went out. With the shorter ride plate, the nose came up again, but there was still a porpoise issue, as the ski went back to hook up/loose/hookup. When hooked up, the Worx grate aimed the hull at the right angle, so the hull was usually angled on the water the right way, but the on/off nature of the hookup was still annoying, and I now knew this could be fixed, having ridden other skis, but how ?
I stared for a long time at pictures of intake grates, and realized that the early TriLoader grate was an extreme 'deep scoop' design. Moreso, it looked as if time had marched on, and the current deep scoops had notches cut from the back of the plate, and mostly smaller scoops, unlike the Riva.....suddenly the light bulb went on.
A Worx 205 intake grate, the smaller one, was installed, and I wished I'd done it years ago. The problem was not with the ride plates.....it was my super duper deep scoop grate causing the problems. I note that none of the current grates looks like this, so I ended up with an evolutionary dead end but due to my lack of other standup guys to play with, never knew.
The Riva grate pulled the entire hull down hard. While it filled the pump, the tradeoff was that the "pull down" was so strong that when it unhooked, the hull would then bounce upwards, until the suction then caught again, pulling the hull down. The Worx grate filled the pump 90 % as well as the Riva, but the Worx grate didn't suck the hull down, and this allowed the hull to work. Suddenly, turning was much, much easier and I could angle the hull almost like my old 440!!!! The Riva grate didn't tolerate much angle, but the Worx allowed me to go way over before the "unhook". High speeds didn't result in the porpoise, and I no longer had to worry about perfect throttle at speed, as the Riva would stop the ski instantly off throttle with handlepole in gut (ow).
In short, this grate pulled the ski down way too hard, was unhappy at angles while turning, and while it did fill the pump in rough water, caused endless porpoising.
So, it comes down to angle..your ride plate determines hull *angle*.
It comes down to suction....your intake grate pulls the *whole hull* down.
A deep scoop pulls the hull down harder than a smaller scoop. I had a worst case scenario with an early design which pulled down way too much at speed, causing porpoising and loss of turning ability.
I feel like it's a new ski.....and the biggest change was dumping the Riva Triloader grate and bolting in the Worx. I think there is too much emphasis on the ride plate, and not enough on the intake grate.
I learned you can overdo both the intake grate and the ride plate. An intake grate does not just fill the pump, it also serves to increase the weight of the hull as expressed on the water.
