Why do I keep reading that some people disconnect the oil injection system and mix the pre-mix them selves???
Having a 2002 GP1200R, Do I need to worry about this issue?

Will a stage 2 install from ISLAND RACING void
my extended warranty I just spent $700 on

or even a stage 1

ANY engine mod will void your warranty, sorry.
That said you can work on your handling set up as much as you can.
Pre mix isn't mandatory but it's an extra safety, and also allows you to use different oils (like amsoil's 100 : 1) that require different mixing ratios.
I unfortunately think that would void your warranty as well, anyway oils like Amsoil will require you to remove your cat con, and this will void the warranty as well.
I don't really worry about this personnaly because I void all my skis' warranties before they even hit the water.
If you want to keep the benefit of your warranty, go to Island's, they will get the best you can get from a "virgin" engine, but you may want more pretty quickly.
11

Do you think the warranty will even come in handy if I kept it stock, I thought they could add some stuff under yamaha or riva supervision that would still keep the warranty.

When I put other pipes on my harley it would of voided warranty, BUT They did the same thing under their care and kept the warranty.

Does that make any sence, What the first major job you would need under warrant , a new Top-end, rings and what not. Will I end up losing big by vioding it, resale n sh!t

Yes it makes sense, like it makes sense in some automobile cases and like you described, some bike cases.
But the point is that a PWC is highly unreliable compared to a car or a bika and there are many more hazard than can cause a failure, like water ingestion, for example, so the manufacturers, used to motorcycle standards, are very disappointed by stock PWCs reliability (and Yamaha has huge problems with their PVs right now) and will do their best to refuse any warranty claim.
It makes life harder on us, who want modded skis, it's a very simple river to cross, be ready to invest in a short bloc and don't count on anybody else but you to finance it.
Once you've made that step you'll be free to make your ski a real screamer.
11

before you do anything put waveater clips in, last thing you want to do is mod it slightly drop a pv and be out a new motor... just because you added something they will void your warrenty, if you have the dealer install it you will still keep your warrenty, pending on the dealer. Also you will pay more in labor then in parts i promise. good luck

What are Wave-eater clips?

Waveeater powervalve clips prevent the pins inside yamahas powervalves from dropping into the cylinder. It's a common problem on any yamaha ski with powervalves. $20 per pin per cylinder. It's cheap insurance!

I was told by my dealer they wouldn't void the warrenty.

Was just wondering posters whether the waveeater powervalve clips are applicable to the fx140 4-stroke or does it just pertain to two strokes?? Thanks.......

2 strokes only

My 2002 GPR had a dropped PV at only 28 hours. I got lucky. The pin didn't drop in the cylinder.