I've thought about maybe doing some engine mods to my 400EX in the future and wanted to know what you all thought. I don't really want to go to a 440 right off the bat. I kind of want to go with a smaller bore for now. Maybe change in the future.

Anyway, what do you all think about maybe a 406 or 416 for MX? I was planning on maybe an 11:1 piston and track cam. What else do you recommend? Anything you would change about my choices? I would like to have more torque, but also get a quicker machine. Any help is appreciated. I want a somewhat reliable machine even after the engine mods. Please help. Thanks.

 

if you don't want a 440 i've heard the 416 is awesoom. i would also get a cam like i think you said and diffenetly a 11:1 or 10.5:1 piston.

 

I don't want to spend mega bucks on my engine right now. Just want to do some mods to start with that will give me good power. What about pistons? What brand would you suggest? Also, what compression would you recommend? I don't really want to go with a 13:1, but I thought 11:1 or so would be right in the middle. What do you think? Would I have to run race gas? Thanks.

 

Anyone?

 

Go with Wiseco pistons.I would run 11:1, and use 89octane gas.If you have engine ping, go to 93.

 

Get the biggun complete and your all set for mx.
Drop your front sprocket one tooth down to a 14 and that will increase your take off speed and if you buy a cam and 11:1 you have to run race gas ( no pump gas)
--------------------->www.clryders.net<-------------------



(bottom-midrange)

 

I would go with the 416 for motox anyway. It revs higher and is better except for more wide open tracks. The best bang for the buck would probably be pipe/416 piston/cam. I would go with the JE piston because it is much much more reliable than the Wiseco. Also you might as well put in a good race cam while you've got the top end apart for the piston. And as far as pipes I'd recommend the Curtis Sparks X-4 or the TC racing modified Supertrapp. Those are my 2 favorite pipes for motox. With 18 inch tires you're gearing should be about right but you may want to go up or down 1 tooth on the rear sprocket depending on how tight the tracks you ride on are.

 

Would the silencer I have now flow enough for those mods? Or would I have to get something different? What about a different header? Would that help? Just wondering, because I've heard from many that the stock 400EX header is good enough. Thanks.

Also, RacerEX, did you race at Loretta Lynn's this past August? Just curious.