Would i have any problems if i just went with the big piston,sleve, and gasket in other words just the (440 kit)

 

You wouldn't have any problems. But you would just get a bunch of lowend power without the cam.Instead of getting power increases at all rpm's.

 

k_Fulk how does that eldebrock carb work i was going to get one of those too.

 

get the fcr 39 carb it works the best for the modded ex motor

 

It works pretty good it gave it a good boost on the bottom and a pretty good hit on top.And its really easy to adjust.

Check ot the January 2002 4wheel atv action they have a carb shootout in that issue. I guess edelbrock is making a round bore carburetor that makes more power too.

 

Big bore EXs seem to have a problem cracking engine cases. I have seen several race motors including my own that have done this.

Adam Smith

99 400EX

 

Where exactly do they crack and why ?

 

All the ones I have seen except mine cracke/exploded out the front where the counterbalancer is. So it is obviously some kind of counterbalancer failure. Mine however cracked at the counterbalancer on both case halves, under the starter and also at the countershaft. I have yet to get mine fixed, but it was explained to me that more than likely my crank came apart and popped the crankcase that is why it broke in so many places.

Adam Smith

99 400EX

 

adam the problem your having is the crank . having the crank welded and reballanced is recomended by every engine builder I know . for the big bore kits . it's the pin they actuly weld . My thought is people that build big bore ex's and dont have this done ! should be ready to buy cases . this is not a honda defect. the added modd's are what causes this to happen ,mostly added comp,and the rev box.

 

Outlaw atv? is the guy's name Larry?? Whats their Ph. #