440 conversion

[trouble661]

my 400ex is starting to burn some oil ( i have to add a little everytime i go riding) do i need to rebuild it or can i just put new rings in. if a rebuild is in order. what can i do to it for under $500. I would do some of the work my self, besides any machine shop work. and i want to keep the same honda reliability.

[BSTURDIVANT]

For general riding and reliability go with 2mm over (416) 10to1 for trail, 11 to 1 ocassional racing. Add a cheap cam such as a Hotcam
stage 1. You can expect the cylinders to be worn too much to go back std. bore, also change the timing chain to CRF 450 chain- cheaper and stronger than 400 chain!

C&D can get you parts and handle head rebuild- all less than 500.00!

[K_Fulk]

Originally posted by BSTURDIVANT
For general riding and reliability go with 2mm over (416) 10to1 for trail, 11 to 1 ocassional racing. Add a cheap cam such as a Hotcam
stage 1. You can expect the cylinders to be worn too much to go back std. bore, also change the timing chain to CRF 450 chain- cheaper and stronger than 400 chain!

C&D can get you parts and handle head rebuild- all less than 500.00!

What he said.
Good cheap rebuild and a little faster.

[Shutang]

You might also be blowing /burning oil out the valve seats. The seats tend to wear out easy. Have your valve clearances checked and be sure that the seals are new when you rebuild. They are cheap to replace at that time and will save you the greaf of another tear down later. I would have them looked at for clearances and seals before I spent all the time/money on a rebuild. If you add a different cam (web or hotcam) be sure that the put in hardened rocker arms....you will bend the stock ones with the larger lobe cam....I learned this the hard way and not only bent the rocker, but bent the valve and had to buy a new cam $460.