I know there has been lot's of probs with 800 valves.

I haven't heard or experienced any probs with 700 valves. Are they different material or is the 700 bore size just happier?

My 03 PROX7 valves appear stainless. No probs after over 3000 miles.
Is the new valve material superior and or required on the 700?
I have also seen both new titanium and new stainless valves, which is better?

No straight answer from Polaris...??

i have been told that both of the big block twins[700 & 800] had
problems with the factory valves. could just be hearsay though.
i believe that they both take the same valves so i think you could
go with the new titanium valves and orange bellows kits. better to
be safe than sorry. watched two of my friends miss out on some
rideing this year because of it. one 02' 700 classic and one 03' 800
sks. neither were a pretty site when they came apart

First the valves in the 7's and 8's are a diffrent size (not interchangable)
second the 02 - 04 valves are made of aluminum, the 05's will be coming with Stainless steel ones from the factory. The Titanium ones are out of Polaris's High Performance Catalog, as strong as steel with half the weight.
I broke both in my 03 800 and finally my dealer got me the Stainless ones under warranty. I have heard of a few 700's breaking valves but those 800 are desine to break, just a time bomb waiting to go.

The 600 and 700 and 800s all have different Valves. The 800 had more trouble than either the 600 or 700. Check your Valves often, look for cracks or stress near the corners of the Valve. Do this even if you buy the newer or better valves. It is catastrophic if the valves break and the pieces get sucked into the lower end.

I would also think that you should do this for any engine that has power valves.

Corsair066

Here's my take on the valve issue:
Heard of 2 high-mileage 01 600's with broken valves , haven't heard of any 700s at all, but several 800s, among them my 02, and 03 and 04 models.

[warning - lots of bitching below]
Have gone through 3 sets of exhaust valves this season, 02 xc800 with SLP single/air box. Jetted conservative, TPS set to 3.85V.
4000 miles on the original valves (750 of them with the pipe). Because of some warping , I had my dealer replace the valves with "updated" ones, black coated valves marked "775".(03 spec?) That set lasted 300 miles before the threads stripped on the PTO valve, and the valve got stuck in the cylinder.

Took it to my dealer and they told me I got wrong valves last time and now they put in some really updated Titanium valves... that set lasted some 6-700 miles before the PTO valve broke off and fell into the cylinder, toasting the piston and scuffs the cylinder real good.
Then my dealer have the nerve to send me a $400 bill and flat out refuses to cover the first set of valves on warranty! , even when they admit that they have valve issues even on several bone stock 04's. They also told me that the last set they put in were the same valves as the first ones!

Also, one of the threads in the mag side ex. valve flange are totally stripped.
(I've yet to see traces of locktite on any of the ex. valve bolts, looks like my crappy dealer never heard of that stuff before...)
[/bitching mode off]

I think I'm going to go for the Ti valve kit for my new ones. And my (ex-)dealer is not going to get their hands on my sled again