lets see some 400ex Pics!

[swampthang]

Lets see who has some 400ex's and what kinds of mods you got. Heres mine!:Bounce 2003 400ex Maxxis razor2,Big Gun full System,Aluminum Wheels(unsure of brand),DG bumber and nerfs,open UNI filter,Set of the crappiest Moose racing bars ive seen!( hey they was $18 and I wanted to ride after I snapped my renthals jumping up a hill)

[jason85atc250r]

Here atr 2 pics of my half a 400ex

[Mr_RPM]

Before i sold it....

11:1 numara piston
stage 2 hot cam camshaft
full Bill's Pipe
Choke removed for better air flow
maxxis razr tires on rear
Mildly ported and Polished

she ran with the big dogs pretty well in a drag race (beat majority of stuff to 300 feet, it always had the holeshot)

[jensenracing77]

the red one is mine and the black one is a friends.

[whyzee]

Nice rides boys. looking to join the 400EX club soon .

[Kerick]

My yellow '02...Had to sell to buy a truck :(

[BTC_ATC]

2002 400ex

[inv3ctiv3]

I have a 2002 400EX, it was in amazing condition when I got it (no scratches or damage and still had the factory paint marks on all the bolts!) I got it for $1800....

http://farm5.static.flickr.com/4135/4773088503_6781348dcf_z.jpg

http://farm5.static.flickr.com/4077/4773728824_c6bfdd4fff_z.jpg

http://farm5.static.flickr.com/4101/4773088859_4567fce6f0_z.jpg

Now it has: ITP Holeshot SR's, CNC steering Stabilizer, Brand new take off 450R Shocks, Pro-Armor Tether Kill Switch, AC Nerf Bars, 450R Pegs, AC Heel kick ups and a Pro Taper Bar Pad.

http://farm5.static.flickr.com/4136/4856696803_69abfd722a_z.jpg

http://farm5.static.flickr.com/4118/4857318696_551539bc2c_z.jpg

http://farm5.static.flickr.com/4107/4972394353_e7edbf018e_o.jpg

http://farm5.static.flickr.com/4108/4972944680_3833c8c8e5_b.jpg

http://farm5.static.flickr.com/4109/4973712539_e05fda1526_b.jpg

http://farm5.static.flickr.com/4112/4973712331_5a1b17ca37_b.jpg

http://farm5.static.flickr.com/4104/4973712189_acb568ec02_b.jpg

[inv3ctiv3]

Right now I want to get some new front tires, new handlebars (I want a higher bar), new bumper, exhaust, uni filter and remove the airbox lid with a re-jet. If you guys have any suggestions on any of that stuff let me know!

[swampthang]

Right now I want to get some new front tires, new handlebars (I want a higher bar), new bumper, exhaust, uni filter and remove the airbox lid with a re-jet. If you guys have any suggestions on any of that stuff let me know!
Well I have the Big Gun full system on mine with the open UNI and jet kit. It was on the bike when I bought it and it is a huge improvement in power all acrossed the powerband compared to my last 400ex that was bone stock. I have a DG bumper on mine and it is TUFF ive smacked some good sized sapplings with it and have gotten tangled up with other quads on a holeshot and its held up awesome.
How are your shocks? can you tell a big improvement with the 450 shock swap? GREAT PICS EVERYONE!! KEEP THEM COMING!!!

Does anyone have a 440 kit with a 10:1 compression piston? Ive thought about adding this anyone have experiance with a lower compression piston instead of a 12 or 11 to 1.

[inv3ctiv3]

Yea the shocks are amazing! Such a good upgrade for the money.

[Mr_RPM]

Right now I want to get some new front tires, new handlebars (I want a higher bar), new bumper, exhaust, uni filter and remove the airbox lid with a re-jet. If you guys have any suggestions on any of that stuff let me know!

if you look inside the carb you will see an old school butter fly valve choke. even when fully opened it still restricts alot of air flow. if your don't mind not having a choke try taking it out and see how you like it (with new pipe and filter as u mentioned) it can always be put back if it doesn't help. With the mods i had done it helped give a bit more high end. Its nice for a free mod thats reversible

[inv3ctiv3]

if you look inside the carb you will see an old school butter fly valve choke. even when fully opened it still restricts alot of air flow. if your don't mind not having a choke try taking it out and see how you like it (with new pipe and filter as u mentioned) it can always be put back if it doesn't help. With the mods i had done it helped give a bit more high end. Its nice for a free mod thats reversible

Does it make the bike harder to start when its cold without the choke?

[jensenracing77]

Does anyone have a 440 kit with a 10:1 compression piston? Ive thought about adding this anyone have experiance with a lower compression piston instead of a 12 or 11 to 1.

do you have the 440 kit in it now and want to drop the compression? or are you wanting to install a 440 kit? i have good info on building 400EX engines if you are interested. avoid the 440 kit. i can build more power from a 416. my 416 will smoke 450s and even many modded 450s.

[Mr_RPM]

Does it make the bike harder to start when its cold without the choke?

well i never had to much of a problem. 400EXs have a accelerator pump and what that does is squirt a bit of gas when you stab the throttle for better throttle response. so on a cold morning hitting the throttle a few times before cranking it over normally did the trick. and thats here in Michigan where it gets cold, id imagine over in Cali it doesn't get as bad. during the warm month i never needed a choke, maybe a few seconds of baby sitting the throttle as she got hot but thats it.
I did have a higher comp piston and that may have helped start it cold too, it all varies

[inv3ctiv3]

well i never had to much of a problem. 400EXs have a accelerator pump and what that does is squirt a bit of gas when you stab the throttle for better throttle response. so on a cold morning hitting the throttle a few times before cranking it over normally did the trick. and thats here in Michigan where it gets cold, id imagine over in Cali it doesn't get as bad. during the warm month i never needed a choke, maybe a few seconds of baby sitting the throttle as she got hot but thats it.
I did have a higher comp piston and that may have helped start it cold too, it all varies

I never use the choke here in CA anyway so it seems like a good mod, I've heard of it before but am gonna wait until I get an exhaust and intake.

[Mr_RPM]

I never use the choke here in CA anyway so it seems like a good mod, I've heard of it before but am gonna wait until I get an exhaust and intake.
yeah, i would too
what type of pipe are you looking to get?

[inv3ctiv3]

yeah, i would too
what type of pipe are you looking to get?

I don't wanna spend a huge amount of money on one so I've looked at the Lexx but have heard mixed reviews. I'll probably buy a used HMF or something like that.

[Mr_RPM]

I like HMF myself. but alot of HMFs are just open tubes with a screen at the end for a spark arrester. which is great for an engine with a high end cam and higher comp piston because they all work together to give a high end power. but with a stock cam and stock piston your going to want something with a bit of back pressure, the stock cam set up is for mid range torque and no back pressure like an HMF is made for high end. its hard to type out

basically,
no back pressure=high end torque
little back pressure= mid range
lots of back pressure=low range

if i were to put and low back pressure pipe on a stock big red (or other low range torque engine) it would take away from the monster low end and add to high end but with the way the engine is set up that would make it slower because it really doesn't have much power in the high end.

if you were to add a high end cam and a higher comp piston your going to gain from a low back pressure pipe because that cam changes where the power curve is. also with high end your going to want to open up the intake as well, like port and polish and bigger carbs (or like removing your choke)

now a 400ex is set up right in between low range and high range so your not going to want something super free flowing unless you set it up that way. now opening up the exhaust and intake a little will help on the 400ex because its all choked up for sound and things. but getting an adjustable pipe will be the best of both worlds so that you can tune to where your power curve is and if you ever mod the engine you can adjust the pipe accordingly.

i have a hard time explaining this by typing haha

[whyzee]

Finally joined the 400EX club today been waiting a long time, almost 2 years. Love the power, 350X like.I gotta say ,I love the stability of 4 wheels. Maybe because I am getting older ??? IDK. Anyway, picked it up today. 2004 all stock except for tires and rims . Not much wear on the cases and the motor has never been touched except for oil changes. Very excited !!!
http://i183.photobucket.com/albums/x217/kumalogan/B2u4uRwCGkKGrHqJhYE7uboGpnBMjoMfyyng_12.jpg

[inv3ctiv3]

Finally joined the 400EX club today been waiting a long time, almost 2 years. Love the power, 350X like.I gotta say ,I love the stability of 4 wheels. Maybe because I am getting older ??? IDK. Anyway, picked it up today. 2004 all stock except for tires and rims . Not much wear on the cases and the motor has never been touched except for oil changes. Very excited !!!
http://i183.photobucket.com/albums/x217/kumalogan/B2u4uRwCGkKGrHqJhYE7uboGpnBMjoMfyyng_12.jpg

Awesome pick up man! I am 100% with you on the stability, I can ride so much faster on my 400EX. Now that isn't to say I don't completely love 3-wheelers and my old 350x but I love both quads and 3-wheelers.

[whyzee]

Awesome pick up man! I am 100% with you on the stability, I can ride so much faster on my 400EX. Now that isn't to say I don't completely love 3-wheelers and my old 350x but I love both quads and 3-wheelers.
Thanks buddy ! I gotta say , coming off of my 250SX ATC I am not quite used to the power of the 400EX. It's kinda shocking, and I just sold my last 250R in january..haha..I must have been crazy to ride that thing ! I guess that's why I sold it, I am loosing a little bit of my wild side, but the 250SX was just way to tame for me.
Anyway, I took the 400EX out for about a 2 hour ride last night and had a blast. I cannot wait for our first snowstorm!!!
Now I know why you sold your 350X..so you could ride some MX tracks !!! that must be awesome. Next quad day at our motocross track I might just show up :)
Gotta love how quiet the stock bike is and still plenty powerfull.