Need a step by step!!

[xtullyx16]

First of whats a better mod for increased horsepower and speed, hotcam stage 1 or a high comp piston for my stock 400ex! Im looking for good useable power in trails, hillclimbing,wheelies,and just ripping it up and down the street! Whats easier to put in cam or piston?? And i need a step by step,anywhere i can find a guide??

[400exstud]

A cam is for you. I feel that it is a better choice for you at this time. Leave the piston until your motor needs a rebuild and then bore it out.

Here is a wonderful guild for installing a cam.

http://www.lspsonline.com/howto/400ex%20hotcam/

[xtullyx16]

what kind of cam should i get?? i heard hotcams are a reasonable brand??

[GPracer2500]

Hotcams are very reasonable. A cam is a lot easier and simpler to do than a piston. There's not many ways to screw up a cam install but there's a whole slew of ways to screw up a piston install. Not that a piston is that hard either--just more steps involved.

[400exrules]

you could screw your timing up when installing a cam....but only if your retarted lol. all you have to do is follow the directions and have some shims, torque wrench, and of course the other basic tools.....easy as pie

[xtullyx16]

well jus to let u know i think my dad or my older bros going to help cause i am retarded with engine i know squat! :(

[lghickman21]

If you put a cam in. you could could just your engine on top dead center with your lobes on the cam pointed down you could leave your cam sprocket in the chain and just bolt your other cam back to the sprocket just like you took your old one out. (will make more sense when you have your head cover off.)

[bwamos]

Originally posted by xtullyx16
well jus to let u know i think my dad or my older bros going to help cause i am retarded with engine i know squat! :(

Nothing better to learn on than a simple, air cooled, single cylinder, single cam engine. ;)

[Quad Dude]

if i were you i wouldnt waste my time doing just one or the other when the power diffence of both is even better than each by themselves and because the piston is only four bolts and a wrist pin away if you got your cam out. the only reason to do one is if ya aint got money for both right now and in that case cam is the way i'd go

[xtullyx16]

well i dunno if i wanna do this..... seems really complicated for me!:( oh well i might give her a swirl.....

[400exrules]

if u want to learn, just do the cam now, take your time,and follow the directions...it will all make sense once you start doing it, and you get the head off. just make sure you have a decent torque wrench before you start to re-assemble.

after you've done a cam, a piston shouldnt be hard. im about to do a piston soon, but im buyin a truck right now so its gonna be longer then i hoped before i can do it.

[exrider008]

Originally posted by bwamos
Nothing better to learn on than a simple, air cooled, single cylinder, single cam engine. ;)

yup the 400ex engine is VERY simple to work on i just did a full rebuild on my engine from the tranny up and im only 15 so im sure u can figure it out. but if i were u i would get a manual cuz u wont get anywere without it. also sence ur not taking ur cylinder off MAKE SURE u dont drop the cam chain or other parts in the bottom of the engine or u will be taking the hole thing apart. what i did to make suer this didnt happen was take a wire and lace it threw the chain and then wrap it around the frame.

[Dannys440]

I did a full motor build like exrider008 did when i was 14.For a cam i have never cam across bolts that need any touque on them(i broke all of my valve cover bolts when i did that 2 years ago, and i was putting any torque on them!).It isnt as hard as you think it would be, the 2 main things i found are set motor at top dead center at all times,and NEVER drop your cam chain.


To do a piston there are about 32 bolts/nuts in which 8 need torque,for a cam there are about 22 bolts.

Those are bolt number in the motor.

[xtullyx16]

Originally posted by Dannys440
I did a full motor build like exrider008 did when i was 14.For a cam i have never cam across bolts that need any touque on them(i broke all of my valve cover bolts when i did that 2 years ago, and i was putting any torque on them!).It isnt as hard as you think it would be, the 2 main things i found are set motor at top dead center at all times,and NEVER drop your cam chain.


To do a piston there are about 32 bolts/nuts in which 8 need torque,for a cam there are about 22 bolts.

Those are bolt number in the motor.

what do u mean to "set motor at top dead center??" ohhh and were could i get a service manual??

[Dannys440]

most local bike shops have manuals.Top Dead Center is when you piston is all the way up in the cylinder.On the left side there are two little allen wrench caps,the big one if for rotating the motor to line in up and the other one tells you where you are.In the little hole there is a notch in the case,on the fly wheel there are lines(4 i think).Two of those lines have the letters F(fire) and T(top dead center),line up the T with the notch in the case and you are set at top dead center.

[xtullyx16]

hmm okay that confuses me but i think i get what ur saying lol:blah:

[-copyguy-]

Originally posted by xtullyx16
what do u mean to "set motor at top dead center??" ohhh and were could i get a service manual??

You got a PM.

[400exrules]

Originally posted by Dannys440
I did a full motor build like exrider008 did when i was 14.For a cam i have never cam across bolts that need any touque on them(i broke all of my valve cover bolts when i did that 2 years ago, and i was putting any torque on them!).It isnt as hard as you think it would be, the 2 main things i found are set motor at top dead center at all times,and NEVER drop your cam chain.


To do a piston there are about 32 bolts/nuts in which 8 need torque,for a cam there are about 22 bolts.

Those are bolt number in the motor.

uhhh yah...you have to torque the bolts on the head....you cant just put em on and snug them down:huh

[Dannys440]

The only bolt in the head that i have ever put touque on are the studs and the acorn nuts(33 ft.lbs.).The valve cover(holds the rocker arms),I have never put torque on those 8mm bolts, they snap to easy.