04-06-2008, 07:14 AM #1
It is starting to make sense to me now
I have just reviewed Mykull's video and now I can see why his ski is so much faster than mine. He really does have a very fast Ultra, congrats Mykull! He smashed the RXP he ran and of course splashed the rider in the face with a wall of water while doing it. This is the beginning of the Ultra’s water conditions, the rougher the better.
I have carefully gone over the video several times and paid particular attention to the attitude of his hull. He has managed to get most of the deep -V- out of the water and reduce his wetted surface. Wow, what a difference it makes. Take a close look for yourself and compare it to your Ultra’s attitude. My Ultra rides much wetter than his, which is probably why my ski is a slug on the top end.
On the other hand my Ultra comes of the hole like gangbusters and kills all the '07 RXTs I have run out of the hole. I have viewed the GH shootout video and the Boat Test video about a dozen times and based on that, my Ultra would destroy the SHO’s in those videos out of the hole.
Are you starting to see my point? I am getting a great hole shot, but losing the top end. It has to be a combination of the ride plate, the wedge and the prop. Horsepower is NOT the answer. We need you pros to jump in on this theory and help solve the problem for all of us. As proven in MyKulls video, his Ultra is indeed a fast ski. What are us plebes doing wrong?
You can view Mykulls video at:
You can view the Boat Test video at:
Last edited by Phil; 04-06-2008 at 07:58 AM.
04-06-2008, 07:35 AM #2
It's in the Rideplate.....
I can tell you that Pipidulce and KawiRyder are running consistent
71, 72 mph via GPS with only ride plate, wedge and removal of
plug under glovebox. I run about 65 - 66 on a good day with stock
ride plate. I intend to put the Riva one on shortly. It's good for
at least 2/3 mph. Some holeshot and maybe handling are reduced.
But how do you measure it??
CHeck out SE Rides for yesterday's run offshore in 4/6' waves.
04-06-2008, 08:01 AM #3
04-06-2008, 08:26 AM #4
- Join Date
- Jan 2007
My wife's ski with riva plate and holes drilled in the glove box cover will do 69+ gps with a best of 69.6 late last summer. I expect her ski to bury that number real soon without a pulley upgrade.
04-06-2008, 12:20 PM #5
If you listen closely, you can hear the RXP hooking and unhooking while the 250X hooks up and moves out. I ride that lake quite often and so far as chop, what you see in the video is nothing. Phil, you are correct about getting the hull out of the water. A Riva plate and wedge are 2 of the easyest things to get more speed out of the 250X. It also likes lots of fresh air. Intake and exhaust mods will give you a little bit on top end but you will see a bigger difference with bottom end and midrange with those changes. As most of us found out last year, some 250's are faster than others. Don't really know why. Phil, I hate to say it but maybe you have one of the slower ones.
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