If you use an angled rideplate and ride in choppy water please read this

if you set the ski up so that it porpoises in choppy water you then run the risk of having the ski get out of control, porpoise badly and do a sharp turn on you - what happens is the ski bounces lands on the front and bingo you go straight and ski veers violently to the left or right - all in a matter of seconds

so if you are using an angled rideplate you need to also do something to control the porpoising
- step the sponsons
- use extended trim tabs
- shim the trim tabs down

and you still need to get rid of the stock grate - it is just plain unsafe at speed

u coulda told me that before i found out first hand. tomorrow, im gonna shim the trim tabs and step the sponsons. thanx. i told my friends before they rode the ski today, to say goodbye to thier loved ones... just in case cuz mine does the violent turn thing... oddly, today, it behaved very well, no sharp turns. thanx again for the advise

question. will the gp800r grate do the sharp turn thing? or is that just a gp1200r event? thanx again

you can get tossed with with the ski doing a violent turn two (unrelated) different ways

1) by using the stock grate (the pump gets backed up with water, raises the rear and the front chines dig in)

2) using an angled rideplate (ski porpoises badly, it lands front end first and the chines dig in and ski turns violently)

Hey Phillip:
I see in your signature that you have a top speed of 73.4 mph. When did you do that ? Was that your big bore ? If it was then you must have that jetting problem resolved. If I missed a post on your speed then " Congradulations". I am jealous.

it was the BB - but it still won't run between 5000 and 5700 rpm - someone else posted they had a similar problem and they fixed it by rebuilding the carbs - that is next

I hope people read and take this thread seriously, I got thrown off my ski and it all happened so fast it was unbelievable, I ended up with just a few bruised ribs, it could have been much worse

Philip are you running the advent with your bb and if so what curve? Fullboogie had some issues in the midrange and he said the advent cleared them up with the 59 curve i think...i'd hafta search the post again to be sure.

I use a R&D CDI with curves they developed for their BB kit (basically 28 degress to 5000 then reduced to 13 degrees at WOT - the Advent single pipe curves have too much advance at WOT so I can't use the stock curves they offer

I did try the stock CDI and it ran fine at 5000 rpm (but then I developed a misfire at 7000 rpm - I got this bug when I lightened my stock flywheel) if I use an Advent or R&D the miss goes away

so I am going to try rebuilding the carbs, if that doesn't help I may try a new timing curve on my R&D with less advance at 5000, something similar to the stock CDI

so until this gets sorted out I have a ski that basically has 2 speeds - slow and fast!

This message has been edited. Last edited by: Philip_GPR,

philip, so the changing of your cdi did play a big role in cleaning up that area.

well sorta, with stock CDI it will run at 5000, but then I get the missfire at 7,000

(what a bucket of bolts my ski is!)