somebody wanna help me out? 416 kit ?

[04fourhunjex]

i did a search but i couldnt find nuthing... i want to put a 416 kit in my 400ex its a 2004. can somebody tell me what i need to know, like, what kind is good... for a 416 kit, like what should i put on it if i get the 416 kit, what stuff do i NEED for the 416 kit i just need the basic info, thanks!

[2004exrider]

its a pretty popular set up on this site. If you want reliablility id go with a 11:1 compression piston so you can still run pump gas also. If you decide to go with a wiseco piston make sure to get xr headgaskets because thats what they base theyre comp ratios on. the ex head gaskets are a little thicker and will make it about a 10.8:1 ratio i believe. Deffinitely get a bigger cam for it. Hotcams is a direct drop in cam, and they suggest the stage 1 for stock bore up to 426. Not to knowledgable about the new stage 2 but maybe ask C&D Racing about it. maybe it would be better. Maybe try pm'ing jak1389 or Cals400ex they should be able to tell ya a little bit more about the 416's.

Jimmy

[400ex28]

JE 10.8:1 piston kit, CRF450 timing chain, gasket kit, new stage 2, 3-angle valve job/new seals, clutch side case cover gasket, bore & hone the cylinder.... thats basic stuff, it all depends how how much money you have to spend

[cals400ex]

ok, i will give you some info. a 416 requires an overbore of .080 or in metric, 2mm's. most people recommend the JE or Ross pistons. some still run wiseco though. another that i would consider is the CP piston. you will want to buy a piston first, then take the bike apart. you will need to bring your cylinder/sleeve and piston with you to a shop that bores sleeves. this way they can match the piston to the sleeve. by the way, the cylinder is what you see on the outside of the bike below the head. the sleeve is inside the cylinder and this is what the piston rides in. the compression ratio of the piston you buy should be below 11:1 if you plan on running pump gas (93 octane). you will want to buy a new head gasket (made for the 416 bore) and a new base gasket. the other ones will be able to be reused. i actually run the cosmetic flexsteel headgasket and the regular cosmetic base gasket. you can buy different thickness headgaskets to adjust the compression ratio a bit. i always run the thin ones to provide a more efficient burn and a little higher compression ratio. also, i would definately get a camshaft. a cheap cam that provides good gains is the hotcams. you need to determine what stage hotcam you need by your riding style. a good full exhaust system will dramatically improve the bikes performance too. i tested a few full systems and slip ons and the good full systems made a really really significant difference.

i honestly would consider buying all of the parts from C&D racing. they know exactly what you need. if you want, you can even send your cylinder to them and they will bore it for you. if you have any questions, let us know.

by the way, make sure you have a service manual and all of the necessary tools before you start ripping stuff apart.

[04fourhunjex]

thanks for the response, where is c&d located? are they around New England?

[cals400ex]

check this out:

http://www.exriders.com/vbb/showthread.php?threadid=142178


if you go to the forum home page and down to site sponsors you will see a forum for C&D racing. you can ask them questions there.