I was wondering if this can be done. I am in need on something to help cool down my engine and keep it running strong. I read somewhere on Honda's website that like after 30 min. or something that you can lose 30% of your power. In the story they were talking about a 2-stroke, can the same thing happen to a 4-stroke? Thanks in advance.

 

If your willing to spend about $200.00 Dirtmods makes an oil cooler for the 300EX. I have one and it works great, and insulation was a snap.

 

I think an oil cooler is a must for serious riding/racing especialy on a modified engine. I used to have an old trx 250x with a Sparks modified engine,and my brother had a trx 300ex with a 350x engine in it. When we would race each other down a road that was about 1 3/4 miles long here is what would happen. We would be even off the start,then I would start pulling away in 3rd gear. When we were both topped out I would have him beat by about 1 1/2 lenghts. The distance would stay that way for a while. At about 1 mile he would start pulling on me,close to the end he would pass me like it was nothing and end up beating me by about 3 lenghts. We switched rides a few times and it was the same. I new what it was but he didnt after the first run. My quad didnt have an oil cooler and I was losing power, his 350x engine did have one and his power stayed constant. $200.00 isnt bad if you want contant hp. I dont know but I'm sure an oil cooler from a 350x or 400ex could be made to work. Call some engine builders and I bet they could tell you if they could or not.

 

You can buy an oil cooler from FST for $95, but to me thats still a rip off. Go to a junk yard and get a transmition cooler, get some hose about 1/4o.d. and 1/8i.d and get 2 clamps. Mount the cooler in front of the shocks and tap into the line that goes from the case to the valve cover. Cut it off about an inch before it goes into the head and flip it so the cut end faces forward. Clamp your hoses from the cooler to both ends of the line and you have yourself a home made oil cooler for about $20. Be sure to fill the lines and the cooler though so your head has oil when you start it.

 

Need4speed,
I was rather disappointed after ordering my oil cooler from fst. After seeing what it included I realized that I could have built that myself. Well lesson learned. Now I tell 300 EX riders to just make there own cooler.

 

just make your own like Need4speed said. It will save you plenty of $ to spend on other mods..

Dan

 

braff1-

can you send me specs on installing that "home-made" oil coller. i do a lot of mx. i do not have a modified engine. i only have the full w/b pro meg, re-jetted, and k&n filter. other than that, nothing major.

thanks,
NT

 

N3COTO,
If you read Need4Speed post just above mine he gives everything you need, 2 pieces of hose,cooler, and 4 small hose clamps. Also, a tubing cutter to cut the metal tube that runs from the case to the valve cover on the right side of the engine 1 inch before it goes into the valvecover. Connect one hose to each end of the tube you just cut and connect the other end of the hose to the cooler's inlet and outlet fittings, now tighten the clamps. You can mount the cooler between the front shock on the front of your quad (the cooler needs to be atleast 5 inches wide to span the distace between frame rails.Be sure to fill the cooler prior to starting the engine.

According to FST this cools the oil that is supplied to the valve train area increasing the oils lubication ability to the vital area. After running your quad up a few hills and down some trail you can touch the cooler and feel the heat, it gets hot.

Dan