400ex rebuild

[jdog75]

Hi i was wondering what pistonkit or individual parts i should buy to rebuild my 400 in december, its starting to smoke and lose power. I would like to know whats the best for my money with all gaskets and piston accesories. I was thinking the stock compression 407 wiseco kit for aroun $250. What do you think

[Foxhound013]

Wiseco is probably your best bet.

[honda400ex2003]

i would go wiseco or JE for the piston, get a hd cam chain such as a crf 450 chain, get a nice stage 1 or 2 cam depending on how you ride and you should be very happy. maybe some hd head studs too if you would like to. otherwise you dont have too many parts to get. gaskets, piston, cam if you like, and have it bored. steve

[honda400ex2003]

the stock stuff with teh 406 would be fine. you could even keep your stock cam if you want and see how it does. maybe a stage 1 to open it up a bit. i am pleased with mine just for an opinion on it. you could get away with a top end gasket kit for about 50 bucks, 70 for a bore on the high side, and 200 for a piston. i would say for 300 you should be up and running again with minimal parts. if you want to get a bit more performance it is about 180 for the cam also. i would say i spent about 550 on my setup in my sig for the motor stuff.

[jdog75]

i started to tear it down today. Im still debating on 407 or 416 10:1 compression. I really don care about performance i just want something that will last a while. I know im going with the wiseco pro-lite piston kit. And i really dont have the cash for cams or any other mods really. any suggestions.

[TRXRacer1]

Originally posted by jdog75
i started to tear it down today. Im still debating on 407 or 416 10:1 compression. I really don care about performance i just want something that will last a while. I know im going with the wiseco pro-lite piston kit. And i really dont have the cash for cams or any other mods really. any suggestions. If you're looking for longevity go as small as you can. You might even be good with a 402.

[speedfreek]

Originally posted by TRXRacer1
If you're looking for longevity go as small as you can. You might even be good with a 402. I agree with the above statement.

Think about what you said, you want longevity. How long do race engines last? The more hp, the more things break.

[jdog75]

i got the engine apart today. Its not scored but it looks like easter. Also i changed my hole thought on the rebuild bc i got a crazy deal. Its a wiseco 11:1 416 with namura gaskets prox cam chain and magnum stage2 cam for $306 shipped all new. And i ground the headers and wrapped them and mildly ported and polished it, cleaned up the head and if anybody cares i got one last ride in before i tore it dow and i just replaces the carrier bearing and put in a durablue locknut to replace my stock one that was garbage and kept backing off(the reason i even had to replace my month old ones to begin with). I paid $75ish Shiped from motosport and it was well worth it.

[honda400ex2003]

sounds like a good deal on the stuff. i had the same problem with the lock nut coming loose and chewing up my bearings. you will like this setup that you will have when you are done. steve

[jdog75]

i see alot of people with similar set ups. I was wondering if it will shut up z400s

[honda400ex2003]

i would say that it should in my opinion. steve

[bigbad400]

i dont get the hype on the z400's. i mean i have one and a ex and i never for a minute thaught the z was faster, stock for stock it has more top speed but thats it, put a pipe on the ex and you got equal everything.

i imagine the fuel injected model has a slight bit more power thow.

[jdog75]

well i have a friend with an 08 z400 se and he always thinks hes cool bc about 100 feet from the finish he pull so far ahead i get roosted and slow down

[jdog75]

one quick question before i go through with that kit listed above i'm going to get. Do you need to put aftermarket valves or springs to put in a stage 2 Cam? One of my friends told me that but he usually is just bustin my balls.

[jdog75]

here she is all together with the wiseco 416 11:1 magnum cam gttstuds madded header yosh with silencer etc idling after fixing my headgasket after it didnt seal after my first assembly

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/wqQBqupHV08&hl=en_US&fs=1&color1=0x006699&color2=0x54abd6"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/wqQBqupHV08&hl=en_US&fs=1&color1=0x006699&color2=0x54abd6" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>

[honda400ex2003]

it runs that is a good thing LOL. i hope you like the outcome of the mods you did, i am sure you will be. steve

[jdog75]

ive been so far befare my gasket started to leak and it was picking up in all the gears at quarter trottle so when i break it in i think its gonna haul :devil:

[honda400ex2003]

it will get better and better, just wait once you think it is the best it can be you will be suprised again. lol. steve

[jdog75]

well today i was suprized again. suprized how crappy the namura gasket is its leaking again somewhene between the metal and rubber so its going to the dump and im ordering a better one prob cometic

[jdog75]

i just ordered a sparkes 87mm head gasket so im hoping this one holds bc it costed more tha the namura kit all together

[honda400ex2003]

you get what you pay for lol. you shouldnt have any problems with the sparks one. it could be a cometic in disguise. lol. steve

[jdog75]

Originally posted by honda400ex2003
you get what you pay for lol. you shouldnt have any problems with the sparks one. it could be a cometic in disguise. lol. steve

it sounds like the cometic one its three layers of steel and its laminated with graphite

[jdog75]

got the sparks gasket and so far it outlasted the namura one.

heres a quick vid from my phone.

<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/VFrH_satLGM&hl=en_US&fs=1&color1=0x402061&color2=0x9461ca"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/VFrH_satLGM&hl=en_US&fs=1&color1=0x402061&color2=0x9461ca" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>