what all parts are included in a top of the line 440 kit?
piston, cam, valves, springs, ???


also... will I need a new carb? if so, which one? I'm keeping the stock airbox lid and snorkel.... no holes either (I ride in a lot of mud and water sometimes)

I don't want a super loud exhaust... thinking about going with the FMF Q4 silencer and powerbomb header

need some clutch mods too, huh?

 

Slowly you will need everthing.
Build the motor well or you will pay a year later.
Do hardfaced rockers and valve springs if you do a cam.
440 if stroked can be alot of diferent displacments. Depends on the stroke.
Stroking costs hella bank.

 

how satisfied are you with your 416 setup?

 

Well, a 440 isn't a stroker (unless you want it to be). You can get a 440 kit from just about anyone. They come with a piston, rings, gaskets, and a new sleeve. You should get heavier clutch springs which are fairly cheap. If you do go for a cam, definitely get the hard-faced rockers, or your rockers will wear out fast. I've been looking into this mod for a few months now...just getting all the info first, before dropping some cash on parts and machining. I'm seriously thinking about going with the 416 or 426, a cam, rockers, porting, valve job, heavy duty clutch, and either an FCR or Edelbrock Quicksilver carb. It's gonna get spendy really quick. If you're on a budget, you can just go with a higher compression piston (stock bore) and a cam/rockers. That can be done for around $600 if you call around and find the right people. Good luck, just make sure you do it right the first time, so you don't have to rebuild a second time.

 

look at powroll they have a whole entire kit of what you need. Powroll 400ex Look at the prefered kit. It looks like a good deal of power for the price.

 

From what I have been told strokers are not the way to go. A guy bought my 400EX bottom end got it stroked to 440 and it broke the cases in less than a month, and this was done by an aforementioned builder in this thread. The reason as it was explained is that the 400EX cases cannot handle the torque generated by the stroker, and sooner or later they will break, in his case sooner. My experience and from what I have seen from others is that the 400EX breaks cases when built up. Mine broke the cases and still ran it basically just wore the cases out.

 

Hey adamsmith, I see on your signature u put houser450 02 finally. Is that the crf450 or is it something else

 

Adamsmith... the guy didnt replace his rod with a very good one obviously. It wasnt the stroke it was the parts and labor he put into it. I have a friend with a 460 stroker and it runs like hell an dnever stops. He has had it for over a year with no problems.

Dsapp... I like the 416 and all but it is to weak. I am boring to a 440 and getting bigger valves this winter to gain that extra HP i am missing out on. I wish i would have done a 440 from the start but oh well. You need to think of how much $$ u want to spend on your engine. My bike kills 440s if they arnt built well. I have only lost to two 440s and that is because they had almost my exact setup with a 440 bore instead of 416. Total i have into my engine is alot. some where around 3k with all the bolt ons, clutch and all. Time to drop anotehr thousand or two into it. Another thing you may want to think about doing if you are a semi gear head is to convert your bike to alcohol. That is in the plans for my bike this winter to. Onyl problem is alcohol requires constatn tuning. 10 degree drop in temperature and you are magically running lean is what i have herd. Oh well. Hope i could help.

 

Lectron carb adds 5 hp but won't idle worth a flip on a 400EX.

 

Mine had a Carillo con rod in it when it broke, and when he bought it from me he had a specially designed rod from everyone's favorite stroker. Both motors were built by top name builders so I think it would be safer to fault the 400EX cases than the labor or parts. Prang the fact your friend has had his so long with good luck doesn't mean it won't break tomorrow. The day mine went it got 3 holeshots on a 12+ rider gate in two classes so I don't think it was showing any signs of failure.

Jay, yes, my current ride is a Houser frame with a CRF450 motor. Bone stock the way I like them.