Are 416,426, and 440 kits reliable for 400ex?

[400exrider0004]

I want to put some sort of power up kit like a 416, 426, or 440 kit on my 400ex. I'm not sure which one is best and most reliable! Thanks

[nosliw]

the closest to stock bore you get the more reliable your going to be. if i were in your shoes (and i will be pretty soon) i would get a 416 11:1 piston, hotcam stage 1 and a port/polish job. should make quite a difference.

[416HiRoller]

Yea I agree. 416 11:1 that way you can still go bigger if you blow your motor up. I really like my 416. It really puts out some power and revs really quick too.

[400exrider0004]

Will a 416 11:1 piston, hotcam stage 1 and a port/polish job last long and what other things would you have to do to make it work? What company makes a good quality of these things.

[rhino738]

Im currently bidding on this quad. You guys are the experts.......so tell me what you think I should be looking for regarding a final price. Are these mods something that I should be leary of? Here's the item # on Ebay 4544477332. Any responses would be helpful. Thanks again.

Chris

[Joe400ex]

damn id that thing has a 440 i wouldnt buy it but besides the fact is a 426 realiable i really want o gte that and a port and polish alsoa stage 2 cam cuz people tell me a stage 1 is almost like stock

[sam the brave]

do you have to port/polish with a bore

[400EX QUADER]

No it just gives it more power.

[sam the brave]

does any one make a 416 kit?
if so how much?
and is it somthing i could do my self?