Ride Plates? ideas!

[GPkiwi]

I have read alot about the GP's bad habit to porpoise and there are many ride plates that can help but not completely cure it. To me they all seem much the same length and think to myself that if they were longer it help cure it better PLUS this would help keep the nose down so on take off you would get onto the plane quicker= faster of the mark so to speak. Also in choppy water would help stop it's tendencies to get air bore when you take off. Surely if you can keep the hull more level on take off you must keep the pump full and get up on the plane faster instead of wasting power on lifting the nose it's put back into forward momentum. Does anyone have any thought's on this as I am thinking of adding some length to the standard ride plate to test it out. Has any one done this before? All comments and idea's welcome please. :emoticonc

[Technical Support]

Re: Ride Plates? ideas!

The length of the plate is only one part of the equation - more important is the shape of the bottom, and the angles it is installed with.

[GPkiwi]

Re: Ride Plates? ideas!

I understand that with the angles and channels made into them but why dont that make them longer? I am on the right track that if longer that this would help in both these area's wouldn't it?

[dtd696]

Re: Ride Plates? ideas!

I put the R&D pro Series ride plate on my 99' GP1200. It extends about 2" from the stock plate. It cut down on the porpoiseing a lot. However, It did cut the top speed down a bit. After trying a few different spacings, I ended up liking single washers at the rear of the plate.

Please post what you go with and how you like it. It seems few post final results on this forum. I'd sure like to see more results from posts.

[Technical Support]

Re: Ride Plates? ideas!

Longer plates mean less speed under certain circumstances. It's all in what the company wanted the ski to do out the box, what they installed stock.

[GPkiwi]

Re: Ride Plates? ideas!

Thanks dtd696, Yes your right their are alot of post's that never seem to get too the final verdict. So I take it, it also helped keeping the nose down? I am willing to drop a little top speed for the sake of getting their quicker and cure the porpoiseing effect. I will indeed keep this post up to date.

[GPkiwi]

Re: Ride Plates? ideas!

Oh hey dtd696 is that what R&D call their offshore ride plate?

[dtd696]

Re: Ride Plates? ideas!

I don't know about the name "offshore". I was looking for an extended ride plate to help with the porpoising of my GP. After looking around the R&D was, IMHO, the best one I found for my particular needs. I got it from parkeryamaha. It is the "Pro-Series". THe plate is also stamped R&D Pro-Series.

Hope this helps. Let me know how you come out on the ride plate issue. What you liked and didn't.

[GPkiwi]

Re: Ride Plates? ideas!

Thanks for that info Dtd, Called it offshore as on thier web site it only listed one for the 97-99 gp1200 which was "Pro-Series offshore" that was all.
OK so I have a guy here who may have a shredmaster ride plate I could try (working on that part) or have to buy it from him as it's been sitting in his shed somewhere. Will lose some top speed with this plate! Also with my standard ride plate have been told that if I take 3mm of the mounting mounts this will help also. Will try this out and get my mate to plane 3mm off. I have nothing to lose giving that a go. I'll let you know how it turns out. So far the plates would be, the shredmaster, (because it's here and can get my sticky little fingers on if he finds it...worth a go) R&D pro-series and the non-groovy Riva are what seems to be on the top of many users ski's with all good results. With thanks for the guys at the Riva forum site.
Also once I've got the plate I'm happy with.........think I will smooth out all bolt holes and edge's to make flush as this would help keep the water flow over it less turbulent. As I have read guys doing this with a gain of 1.5mph in doing all the grate and plate bolt holes and filling in every crack and join to make all one smooth area. That's worth a go too isn't. I'll keep you upto date with my finding's.;)

[1200ks]

Re: Ride Plates? ideas!

The shredmaster is hands down the best at reducing porpoising. And yes, it has about a 2" "tail" vs. the oem ride plate on the '97/'98 GP's... and much longer than the oem rideplate on the '99 and later GP's. But it does take about 2-3mph off your top end. A good alternative is the Riva Limited Edition (or now called the "Performance") Ride Plate with a couple of washers under the rear bolts. This set up will remove 90% of the porpoising but only cost you about 1mph of top end. I've also tried the R&D plate. It didn't seem to have the "tunability" of the Riva plate. I've still got it if anyone wants to make me a reasonable offer for it.

[GPkiwi]

Re: Ride Plates? ideas!

Thanks 1200ks I'll keep that in mind about the ride plate! Thanks for your input all helps get a better idea of what's worth while.:emoticont

The Riva plate comes with the shims doesn't it?

[tripletrouble]

Re: Ride Plates? ideas!

I too had this problem when I got my ski in '98. It is the newer style without the factory plastic trim tabs. The biggest fix for mine was the Riva trim tabs. They are only about an inch wide but make a world of difference. Riva did alot of research on this problem back in the day when this ski was new. They told me it was the fact that the factory step at the back was not perfectly square and created uneven turbulance back there. To test this they just sanded the fiberglass square. This was not a permanent fix because the egde would eventually wear back down. Thats why they made the trim tabs out of aluminum. I also have the shredmaster ride plate that I got before the tabs and it did help a little but I would not call it a cure. It does help with the handling of the ski and the straight line tracking in rough water, so I left it on.

I don't know if Riva still makes the tabs. If not, try pro-tec or tau-ceti which I think also made them.

Good Luck

[GPkiwi]

Re: Ride Plates? ideas!

Thanks tripletrouble:) So I take it you are still happy with the Shredmaster plate still been on your ski? Yes mine is the same without the factory plastic trim tabs on their. Would put them on last and set-up best I can. I putting these mods on,
Jetworks-done
R&D intake grate
Worx sponsons
Ride plate.........working on that one, could be Riva (non-groovy) R&D pro or Shredmaster.
Riva or Pro-tec quick turn nozzle
Solas blueprinted XO or J prop........concord still an option.
Not looking for top speed but great handling and good acceleration. Does anyone have any comments on that setup?

[1200ks]

Re: Ride Plates? ideas!

1) Replace the plastic trim tabs with billet aluminum tabs. The plastic ones can peel off at high speed and throw you from the ski. The are kind of pain to replace, but if you have already replaced the sponsons then you know how to remove everything out of the back compartment to get to the bolts that hold the trim tabs in place.

2) You will not be able to turn a J prop if your engine is basically stock. Actually, you will be able to turn it, but your engine will be really bogged down and will probably not be able to reach peak rpm which is very hard on the engine. I run out of the box XO's on both of my ski's. They give great holeshot, but think I could do better on top end if I had them tuned. My plan is to send both to Carl @Island during the offseason to have him "optimize" them for my particular ski setups.

[GPkiwi]

Re: Ride Plates? ideas!

Wow awesome 1200ks, But what pitch is the XO's you run?

Have read alot about Island racing and seems to be the top bloke on setting up the props. Really appreciate your advise. As with prop and pitchs is getting to be a little minefeild.