another 400ex rebuild thread

[mineralgrey01gt]

My 400ex needs a rebuild and so I decided to put a little money into it to get it ready to go (probably more money than i should lol) So far this is all the new pieces going on it:

1. Douglas red label fronts with grooved radials
2. Douglas beadlock rears with 18" turf tamers and yellow NAC'S mud caps
3. 416 bore with piston and COMETIC top end kit
4. Stage 2 hot cam
5. CRF 450 timing chain
6. Fresh valve job and a nice cleaning of the head before I port it

Here is a couple before pics:

http://i673.photobucket.com/albums/vv91/lilzilla2008/400ex029.jpg

http://i673.photobucket.com/albums/vv91/lilzilla2008/400ex031.jpg

http://i673.photobucket.com/albums/vv91/lilzilla2008/IMG_0339.jpg

ill post pics up of it when i get the parts for it in.

[55stone]

sweet man.. should be fun..good luck

[mineralgrey01gt]

just ordered all my stuff, should be here by the end of the week hopefully

[Motoman723]

Hey man you considering any power on that thing?

[mineralgrey01gt]

Originally posted by Motoman723
Hey man you considering any power on that thing?

what do you mean?

[Motoman723]

Haha like powercoating...frame, subframe, arms, wheels?

[mineralgrey01gt]

lol after i re-read it i thought you meant powdercoat lol. Power kinda threw me off lol. I will in the future but not right now. Frame a-arms and swinger (going aftermarket down the road) will be black or that yamaha color they use on the older yfz 450 frames, the red color. I always liked that color. If i do that then im going with the white carbon plastics. I also thought about going completely black. Everything black from the wheels to the grips, no chrome what so-ever. Might run the black/gray carbon plastics with that setup if thats what i decide. Im going to powdercoat a bunch of stuff myself once i get the setup all done. Ill be able to do all the small stuff then ill send my frame to Pappy and have him do that.

[mineralgrey01gt]

parts are starting to come in!

http://i673.photobucket.com/albums/vv91/lilzilla2008/photo3.jpg

also i am getting a 450r carb. Im waiting to hear back from the guy on the price.

[Motoman723]

haha ya that was my bad...thought i put powder...but i forgot the D :p

[mineralgrey01gt]

little update, i did get my oil filters in today (no big deal on that one) and my rear wheels and tires so i put the fronts and rears on today. Man im likin the way it will look, but looks like ill need to lower my rear a little, sits a little high with the plastics on (didnt get any pics of the plastics on it) Here we go, set up is douglas red label fronts 3/2 offset with grooved radials, rear is douglas red label beadlocks with grooved turf tamers:

http://i673.photobucket.com/albums/vv91/lilzilla2008/photo6.jpg

http://i673.photobucket.com/albums/vv91/lilzilla2008/photo4.jpg

http://i673.photobucket.com/albums/vv91/lilzilla2008/photo5.jpg

[johnnynonails]

tbh, i think the rear sits ok

[mineralgrey01gt]

another update, the rest of the parts came in so now im waiting for the cylinder to be bored. Im about to take it to the local place and pick up a few more gaskets that i wanted to change so it will be good to go on the fresh motor.

http://i673.photobucket.com/albums/vv91/lilzilla2008/photo7.jpg

[mineralgrey01gt]

well i forgot to ask the local place how long it will be so i called up there and it wont be ready a week from friday:eek2: i was hoping to have it going this weekend but thats a no go. I guess it gives me time to get my 450r carb in and have it all done at once, damn i hate waiting :mad: :mad: :mad: :mad:

[mineralgrey01gt]

going to tear it down tomorrow to the bare frame and get it ready for some paint and such. Going to clean it up nice and get it ready to go. Might paint my beadlock rings also. Looks like ill be going with white carbon plastics down the road, what color frame should I run? Also dont want to run a black or red frame so thats out of the question.

EDIT: after doing some looking at paint colors. Im going with a burnt orange metal flake paint. It should look killer with a black base coat. I thought about doing the Mirage paint and have it flop from green to blue but im passing on that and going with the burnt orange. Itll look killer with the white plastics down the road, also doing black bottom arms and thinking about keeping the red tops but i think black tops might be a little better IMO and a black swinger.

[lester985]

have fun with the rebuild if u need some more boreing just let me know i have a shop in new iberia and wecan bore while u waite

[mineralgrey01gt]

Originally posted by lester985
have fun with the rebuild if u need some more boreing just let me know i have a shop in new iberia and wecan bore while u waite

man wish i would have known that. I dropped the cylinder off this morning at our local shop. Next time ill definitely send it to you since their turn around is always kinda slow. Said there is 8 cylinders ahead of mine that need to be bored

[lester985]

it will cost about 40 bux

[mineralgrey01gt]

damn its $60 here, just new iberia is a good ways from me. Im about 35 min east of baton rouge

[lester985]

i just put the hd head studs and went from 416 to 426 and xr 400 head gasket and what a big difference

[mineralgrey01gt]

I think the COMETIC kit i have is for a XR400, not 100% sure. Which compression piston are you running? Im going with 11:1

[lester985]

i have the same but its a je piston the 416 wiseco i had in it had about 8 to 10 hours on it and i sold for 75$ yesteday

[mineralgrey01gt]

sweet, so the 426 was a nice improvement huh? i thought about doing it but i wanted to keep that bore for when i have to bore it later

[lester985]

with shaving the top of the jug 20 thousands and the xr 400 gasket its a big change like learning how to ride all over again

[mineralgrey01gt]

little update, got my 450r carb in and i picked up my throttle cable for it. Im going to hunt down some fuel line that fits this carb. I think my local shop has some.

[shawnmcc]

what size front and rear tires did you use 18/9.5/8 ?

[mineralgrey01gt]

the rears are 18/9.5/8 and the fronts are 145/xx/10's or 175/xx/10's. Ill have to look, they are grooved Riken trailer tires

[shawnmcc]

thanks

[Motoman723]

Is there a beneifit to these radials? Why not regular mx tires?

[mineralgrey01gt]

Originally posted by Motoman723
Is there a beneifit to these radials? Why not regular mx tires?

they handle really well in dirt, mud or wet ground they dont turn too well from what i hear. I never ran them but from what people say they handle very well.

[mineralgrey01gt]

well the cylinder is ready so this thing is going together tomorrow. Ill post up finished pics of it and ill take some of during the build.

[mineralgrey01gt]

well ran into some trouble.... I guess when the guy put the thick ring on the piston to bore it he stretched it out and made a weak spot on the ring. Well it just so happened to snap the ring in 1/2. Now im waiting on new rings to come in. Man im still pissed!!!

[Wr3sTl3b0y]

thats funny haha i had my neighbor(drinks too much for his own good)
doing my new piston rings when i wasn't around got my 4 wheeler back smoked like hell took it back apart their was a chunk missin from my piston which we belive he broke on his bench but wouldn't admit it after that i put the 440 kit in it bc i needed a new piston

[mineralgrey01gt]

Another update, found a local shop with the rings in stock so it's getting put together tomorrow.


Haha damn dude that sucks!!!!! Those 440 pistons aren't cheap

[mineralgrey01gt]

well its up and running but I still think the jets are off some. The exhaust will glow red after just a few minutes of running. I have a 175 and 50 in it. Do i need to drop the 175 to a 172 or so?

Also for anyone who said they got the 400ex fuel line to work, im sorry but im calling bs on that one. No way that fuel line will stretch that far. The same with the intake boot, unless my 450r carb is some oddball one. Ill be ordering a 450r intake boot and fabbing up a box.

also can someone please tell me where the air screw is at? I must be blind because i couldnt find one on my carb