I am currently building an 01 400ex engine with the big bore 440, i am awaiting the arrival of my D.I.D timing chain to put the crank case back together but i was wondering what kind heavier duty parts should i put in it to prevent the common issues with the 440 big bore kit. I heard that they have overheating problems? And like to blow head gaskets like no other. Thanks!

 

The air custom air shrouds that you can get on ebay should help keep the engine a little cooler. If you dont already have them.

I dont really think there is anything else that you can put inside the engine to help woth the temp


http://www.ebay.com/itm/Honda-TRX400EX-TRX-400EX-Air-Engine-Cooler-Shrouds-Scoop-Kit-CFM-Performance-/380719156733?pt=Motors_ATV_Parts_Accessories&hash=item58a4a14dfd&vxp=mtr
Also, ive also read that if you change your spark plug to a DPR9Z, its said to run cooler? But im no professional so dont hold me to that. =)

I run a DPR9Z in my 400 that is bored slightly over stock but still runs great.

Good Luck!
Chad

 

I dont know if you might be able to help me with this but i just bought a 15" x 10" and 3/4" depth transmission cooler, would the cooler be to big and would my 400 lose oil pressure if i put it on there to cool it?

 

Do you mean you bought a bigger custom oil tank? like this?

http://www.ebay.com/itm/Aluminum-Oil-Tank-With-Cooling-Tubes-Cooler-Honda-TRX-400EX-400X-TRX400X-CFM-/171112017163?pt=Motors_ATV_Parts_Accessories&hash=item27d7122d0b&vxp=mtr


I know they sell those But I have not seen a transmission cooler. Nor have i seen a custom made Oil cooler. But thats pretty cool (no pun intended).

Im not sure of the fitment of the part you ordered, but i dont "think" you will lose oil pressure but you will certainly need some more oil if your running more Oil line through there.

Chad

 

Thats what it looks like im not sure if it would work but thanks for the help.

 

I have a 4 stroke tech oil cooler that redirects oil right to the cam and head. It helps keep my 500 bbk cool alot. Also Spal makes a 4" waterproof fan that fits on the factory oil cooler.

 

Okay thanks maybe I can figure out something. Thanks