I have to tear down my X engine due to a shifter fork failure(well that is what we think it is, but haven't opened it up yet).. I figured I would have some cash into the parts plus I figured while it is open, put in a new piston and rings.... Then Iwas thinking since I am goign to do that, why not put in a cam and hi-comp piston, maybe a bore(it will need one)... Well i got the top end apart so far and there is some play in the rod, so I was thinking of maybe goign with a Powroll stroker crank and HD rod....

So all in all, i was thinking while it is apart why not go with:
Cam
Hi-comp overbore piston
valve springs
stroker kit(crank and rod)

But then I was thinking, I would have a good deal of cash into all of this, why not just get a 350X engine? I have found a few cheap ones on the net, but am afraid to buy them due to not being able to look them over before I purchase them...

A little overview on my X, i use it for trail riding and some MX and XC racing(occasionally)... I am also building an R. Once the R is done, the X will be my winter rider and play bike while the R will be the racer and only ridden in the summer(main summer bike)..
I figured the extra power will do well in the winter snow, but should I sink all that cash inot it or just fix it and put it back to stock and sink the cash into the R?

I figured since I plan on keeping the X, why not put some cash into it now and I wont need to down the road...

What do you guys think?

 

My bro. and I put a 350X engine in a 300ex once and it was mean. I had a 250X with a Curtis Sparks engine and it was even more mean. If you could find a 350X engine cheap I would just go that route. That is if you dont mind waiting for an exhuast to be made. Maybe Powroll already has some made up. If you cant find one for less than an engine kit from Sparks I would do the engine kit. Sparks engines are fast. My bro. told me the other day that he knew where 2 350x engines are for ... Well I'll just say I could get them both (they are brand new) for less than half of what most places charge for one. I dont know if I could sell them though since the market isnt as high with the 400EX out and all. If you do the engine kit go with a Lectron Carb. and porting.

 

I wouldnt go the 350X route. Parts will become harder to find for it as the years progress because it's been discontinued for so long. If you get a stroker kit for it get a new rod. If you don't all they do is stretch your rod and that sacrafices reliablilty. If you get the cam and the piston and springs your engine is going to want to breath. I'd get the head ported a little bit and maybe even consider some oversize valves. I got the 330 kit for the EX's on my X which bumps it up to 288 but hell I figured call it a 300. I reccomend getting powrolls exhaust for the X. I have it and I have nothing but good things to say about it. It's cheap and you get a lot of bang for your buck. You'll notice lots more power in your X and you'll be stompin the EX's and 350X's if you go the route that I did.