what is the best 416 kit??

[trailrider894]

so i'm looking into boring my 400ex up to a 416. what is the best kit to do it with??? like who is the best people that make the kit?? and what all is required?? do i just get the kit and install it or do i have to have my enging bored and honed first??

[04TRX400EX]

As far as I know, there are not many companies that make a 416 "kit" ... 440 yes, 416 no. Usually people will just choose some products depending on what you want to achieve with the engine. A standard kit would consist of a piston, rings, gaskets, and usually a higher performance cam to match.

If you want to run pump 91+ octane gas, consider either a JE 10.8:1 piston or a Wiseco 11:1 piston. CP also makes very good pistons but I believe their 416 bore is 13:1 compression so it will require race gas. The popular cam choice would be a Stage 2 Hot Cam.

I do not know the particulars of installation but a professional mechanic or engine builder would be my recommendation. For a 416, you don't need hardened studs or any of that.

[wes350x]

When I built my 416 years ago I used a ROSS piston. Look it up, it was the lightest piston which is what you want. Very good quality. The kit is for the XR400, but if all fits. I think the comp was 11:1, which is suitable for pump gas.

[04TRX400EX]

Originally posted by wes350x
When I built my 416 years ago I used a ROSS piston. Look it up, it was the lightest piston which is what you want.

Not necessarily. Light pistons are great for improving throttle response by means of a lighter piston revving quicker. However, lighter pistons often compromise reliability and strength. Think about it, if a piston is physically lighter, there must be less mass. Less mass must equal a thinner gauge connecting rod mount, different ring gaps, something.

I only bring up this point because my buddy just blew the engine on his 450R because the piston (an aftermarket, higher compression, "lighter" piston) cracked in half causing major engine damage including a snapped rod, bent valves, and a damaged head. So maybe you don't want the lightest piston but one that focuses more on strength while minimizing rotating mass.

[trailrider894]

well then who would you reccoment gettign the piston from??

[trailrider894]

and if i get the 416 kit do i just install the pisont and hot cam and that is all?? does it have to be bored and honed by a machine shop?? and how much would it cost (at least a general price) to have the 416 installed professionally??

[dezertboyjd]

ok hopefully this will help......

1) decide on a piston brand. wiseco or je is what i prefer and run in all my machines. you need an 87mm wiseco either 10:1 or 11:1 compression which will put you at a 416cc. or an 87mm je which will put you at a 415cc. (i dont think je makes a lower compression piston in the 87mm less than the 12:1). i run the wiseco because i can get lower compression and run pump gas.
2)make sure you get new gaskets
3)take your piston and cylinder in to have it bored and honed to the correct size
..basically it for making it a 415/416

but i would strongly recommend doing a satge 2 cam, heavy duty cam chain, valve adjustment and if needed a valve job, and new clutch springs and plates along with the piston. mine as well have basically a completely fresh motor. and the improvements will be very noticeable!

just my 2cents

[BigLuke]

why would the wiesco 87mm be 416cc and the je 87mm be a 415cc, same size arent they???

[Honda#4]

The only 416 kit I know of is the goldenwest cycle kit, its around $330 I think you get a cam gaskets and piston and rings. I was gonna buy the kit but I didnt know what gaskets they run so I did everything seperate.

[morse250r]

a "416" is only 80 th over bore of stock
you really could use a honda 80 over piston and make a 416 other brands will make a high comp piston magic racing cp ind weisco ect i wouldnt run over a 11.5/1 and a stage 2 cam my buddy also put on a 450r carb runs great

[dezertboyjd]

dont ask me about why wiseco's 87mm and je's 87mm make different cc's. everything i have ever seen has showed me that. never made sense to me but all im doing is stating the facts

[trailrider894]

well how much would it cost (an estimate) to have it bored?? and what compression is best for regular pump gas??

[morse250r]

11.5/1 is pump 45 bucks a hole

[liex21]

curtis sparks makes a pretty nice 416 national kit and a 416 kit if you go on their website its pretty easy to find

[awsomeaussies]

I got mine from here...
www.powroll.com

[gojk]

Just buy the JE 87mm 10.8:1 piston. Then buy the cometic flexsteel headgasket. Get some viton valve stem seals and your choice of cam(I prefer the Hotcam Stage 2).

I reuse the valve cover gasket, and use liquid high temp gasket maker for the base gasket(just make sure to use a very thin layer and don't block the oil ports).

The bore and hone will run anywhere from $40-80 depending on where you take it. You can take it to your local shop and they will send it off for you. Make sure you take your piston because they match the bore to the piston.

Once you get the cylinder back, slap it all back together, adjust the valves and breakit in.

Total cost should be ~$400. And there is a very nice increase in power. Also C&D Racing should be able to get you all of the above listed parts.

Added insurance would be to install heavy duty head studs which would be an extra $150 with FDO installing them. Maybe send the cylinder to FDO for the bore and head stud install.

[awsomeaussies]

It always starts out cheap... but then you'll want to add the Hotcam, hd timing chain, port and polish, 3 angle valve job, maybe studs, bigger carb, etc. :blah: Whole thing ran me around $800

[honda400ex2003]

I love mine with the stage 1 for low end. It pulls hard even with just the 10:1 in it. much faster than a stock 400ex. It cost me a little less than $400 finding the best prices on everything on ebay and others. steve