Big Bore 440 Kit

[djm137]

I was looking at this kit for my 05 z400. My question is how bad does this affect the reliability of the quad and how often will I have to rebuild? Is it worth the power increase? Thanks for any replies.

[trx400exxracer]

Go to www.fourstroketech.net they have a 440, 463, & 500cc piston kits for your quad I dont know anything about them never had one

[MXridin841]

Athena has a 440, 435, and 434. They are all extremely reliable. Wiseco has a 440 kit as well but then athena is the better deal since you get a new jug and everything else.

[bansheefever]

just ordered the 463 we will c how it runs...

[RidrKFX]

My friend has a 05 z400 and hey has put hotcams, full system yoshi, larger radiator and he put a 440 athena kit in with just the piston and jug. and about 2 weeks later his values were floating and soon after that he dropped all 4 of then and so he spent $1200 to get a new crank, jug, piston, and top end. again a 440 Athena kit. It is worth the power increase because it will take a 450r with ease but have to be careful and make sure you do everything right.