Fzr,fzs,sho buck

[jefros]

I am the rider that got thrown from his FZS with a Riva grate. (actually full stage 1 from Riva except ride plate from R&D). The ski never acted unpredictable until that fateful day when I was bucked. Smooth water (no f..ing logs) and I slow down to set up for a turn at 70 when it jumps to the left and I am airborne. This happened Memorial day and I am still messed up. I ripped a lot of muscles in my groin and separated my pelvis. After 3 months of failed conservative therapy, I am going to have surgery to put a plate across my pelvis this Friday. I have recently inquired on this forum about possible changes with the 2011's that would prevent these incidents from happening. It does not seem like Yamaha has done any modifications? Anyways, sorry for the rant. As far as the original poster goes. I am sorry this happened to you. Thank God you were not more seriously injured and the ski did not injure someone else as it crashed into the dock. My empathy is with you.

[Lezzosoap]

This has reminded me to order a grate and seal kit as i havent done this yet, havent been chucked yet so im not risking it, have just ordered one today. Thanks for the reminder

[BPnta]

I am the rider that got thrown from his FZS with a Riva grate. (actually full stage 1 from Riva except ride plate from R&D). The ski never acted unpredictable until that fateful day when I was bucked. Smooth water (no f..ing logs) and I slow down to set up for a turn at 70 when it jumps to the left and I am airborne. This happened Memorial day and I am still messed up.

There's got to be something in common with all the skis that have bucked. I don't believe it's just random.

So from what I understand a tunnel pressure that's too high causes it. Jefros, what was the exact setup of your pump/rideplate?

[jefros]

To be honest, I dont know what my setup was as far as shims, washers, etc. The dealership installed all the components of the stage 1. I had worked it into the sales price of the ski. As mentioned, it was all Riva except an R&D rideplate because the Rivas were not available at that time. I agree that not all the skis are doing this but just some. The question is "do they all have the potential" or "are some predisposed because of different set up/ assembly at the factory"? I tend to lean toward the "all have potential side". My ski never acted unpredictable. I had driven it hard and in all kinds of conditions. (the irony is that this happened while I was just cruising around and not hotdogging!). Their is nothing obviously wrong looking at the rideplate/inlet/pump area. Thus, why all of a sudden does it buck? Hopefully Yamaha will get the message and fix this issue before someone dies (though, I would bet they are already too late).

[mikeFZR]

There's got to be something in common with all the skis that have bucked. I don't believe it's just random.

I bet it has something to do with the transom plate alingment. There have been a few people post pics of transoms that are way out of alignment which would cause an uneven water flow to the pump.

[BPnta]

I bet it has something to do with the transom plate alingment. There have been a few people post pics of transoms that are way out of alignment which would cause an uneven water flow to the pump.

That would definitely explain why it happens to stock and modded craft.

I was digging through some old threads and found this:
http://www.greenhulk.net/forums/show...FZR&highlight=

I can't seem to understand what Rocketman is saying, is he suggesting it would be safer not to seal the grate?

[mikeFZR]

That would definitely explain why it happens to stock and modded craft.

I was digging through some old threads and found this:
http://www.greenhulk.net/forums/show...FZR&highlight=

I can't seem to understand what Rocketman is saying, is he suggesting it would be safer not to seal the grate?

I think he is saying that a non sealed pump allows some water to escape... just like the jetworks valves do.... which means less pressure in the pump = less chance of getting bucked. This seems possilbe but there is one major issue with his theroy.... there is no way to meausre how much water is escaping through the non sealed pump.

Also, I have my entire pump sealed... grate, plug inserts, transom, everything.. the whole 9 yards and I dont have any problems at all.

[Rocketman]

we also have one boat complety sealed and no problems so far,,,, but yes its a problem of too much water and the pump can not proess or spit it out so it revereses flow or belches back and lifts the rear of the ski and unfourntely (unlike the gpr) turns.

[YoYamma]

I sometimes wonder about the adjustable trim... that's the one thing that is constantly changing on both stock and modded craft; I have noticed when the trim is all the way in the "bow up" position this forces the nozzle up quite a bit in the rear, and as a result, a considerable portion of the jet wash is being partially blocked by the reverse bucket. You have to stand off to the side while its on the trailer to see this clearly. Could this be related, who knows... just a thought. I have also wondered what is it about the design of the R&D grate we are using, that seems to be preventing the stuffing effect.

[jefros]

Trim was neutral. I dont seem to change it much as compared to my Seadoo with the electric trim.