1999 400EX Top End Advice

[maxman]

I picked up a 1999 400EX in great shape with nerf bars, fancy pipes, and a bunch of other stuff for $300. Very clean quad! The dude ran it out of oil. It cranked over well, but compression was almost zero so I pulled the top end and found a gouged piston and scuffed cylinder. Going to bore the cylinder out looks like .020, but not yet sure. Going to rework the head.

Any suggestion to what manufacturer piston and top end gasket kit to get.... or avoid?

Is there a easy way to make sure there is not "chunks" in the bottom of the case?

What else? This is my first quad.

I do not intend to pull the engine and want to keep total investment below $500.

[CJM]

JE or Wiseco pistons, 11:1 compression, hotcam stag I or II (I is lower to mid, II is mid to upper rpm where it makes power), 450R carb, cometic brand gaskets.

You can look into the bottom by removing everything on top (gotta anyways to do this job) and remove the piston or look around it-you can see inside the case then for chunks.

[honda400ex2003]

pretty much what cjm said, go with cometic gaskets, je or wiseco stage 1 or 2. the rest is an added bonus for fun those things alone will be a great setup. steve

[bherriman]

Running an engine is never good. On anything. I wouldn't run it without replacing crank and rod bearings checking the cam journals and every other bearing in the case..but thats just me. If he ran it with no oil long enough to actually gouge the piston, imagine what the bearing surfaces look like.

[drew416ex]

Originally posted by bherriman
Running an engine is never good. On anything. I wouldn't run it without replacing crank and rod bearings checking the cam journals and every other bearing in the case..but thats just me. If he ran it with no oil long enough to actually gouge the piston, imagine what the bearing surfaces look like.

x2. While its down and apart go all the way through it. It will take a little more time and money, but you wont have to do anything else to it for a while.