400ex rebulid need help!

[81 clark racing]

i just picked up a 400ex motor. it burns oil and needs a rebulid. can someone tell me EVERYTHING i should get, i want to do a 416 bore. and i all ready have a stage 2 hot cam. so im looking for a list of everything i should or need to get. i want it to be realiable.thanxs steve

[81 clark racing]

any body.....

[Pappy]

If you order one of the "kits", it will come with just about everything you would need. I would get a new timing chain while your digging into the engine, and a call to Colby at C&D Racing would be a good first step, he could give you a few tips on what to check on the head as it could be time for a valve job as well. no sense in doing the jug and not atleast some new valve springs and a valve job

[f4istunna]

I agree w/ pappy, Definatley do the timing chain while your in there its easy and prevenative maint even if not needed. CRF chain is way to go and cheaper than oem.

you can do it w/ basic tools nothing special needed really.

Cam chain
topend gaskets
piston kit of your choice
have cylinder bored to piston
good time to do valve seals and check the head out
Put it together add oil, adjust valves and break in.

Change the oil after your break in also is a good idea to get any metal particles or dirt that may have gotten in while the top was off

obviously up the compression. Depending on your price range this is what I would get for a 416.

-bore 416cc
-10:1 Wiseco or 10.5:1 JE piston
-Port and Polish
-stage 1 hotcam (stage 2 is fine too)
-CRF cam chain
-450r carb
-K&N air filter with outerwears
-HMF slip on with the stock header welds shaved down

[TRXRacer1]

Since you're asking about what you need for a bore then you need a piston kit (piston, wrist pin and clips), cylinder bored to the piston and a good gasket kit like Cometic. You'll need the big bore kit as the stock sized gaskets won't be big enough for your 416. Also I'd pass on the cam chain. It's cool that you can put a CRF chain in there but unless the current one is stretched out there is no point other then paranoid insurance and it seems to be the "in"thing to do. All you're doing is a stg 2, nothing wild. I'd pass on the valve springs too unless there is something wrong with them. I doubt you'll get any float or reliability issues with what you have. If you go over 11:1 I'd have some steel inserts installed by a machine shop in the cylinder head for the head studs. Other then that just do the basics like get a book and torque everything to spec. Good Luck