how to make a 400ex as fast as a 450r

[utah250r]

i am thinking of selling my wife's 06 450 to get a 400ex. i want to know if theres a really reliable way to make a 400ex as fast as a bone stock 06 450? if possible i would like to not have to put a cam or anything internal in it. thanks for the info

[MtnEX]

Why are you wanting to do this?


If I had to guess, I'd lean towards the 450 stalling easy, being high-strung, a shifter hound, and not quite torqy enough on the low end?


If this is the case, here is my advice to you. Invest some time and money into re-gearing... which might be a bit of trial and error unless someone can help you that has done the same.


Take it from a guy who has went from a 450 (YFZ) to a 400EX...

That's what I thought of the 450's. Loved the mid-range and top end... but I wasn't sure there was a practical re-gearing solution... plus I figured a 400EX or something would be super simplistic (air cooled, etc) and low maintenance.

In the tight woods I think I like my 400EX a little better. It luggs a lot better down low and slow. But I still shift a little more than I'd like because it does not have the horsepower or the explosive response to pull an upper gear like 3rd on out of a slump with it's midrange.... and trust me, my legs are cussing me out on hot days because of the heat rolling off it.


I myself am starting to think that the ideal quad would be a 450, will all mods focused towards bringing up the low end grunt to compliment the rest of the performance....

I'd love to try a KTM 525 powered quad to see if it has it off the showroom floor.

My 452cc GT tunder mill is quite pokey from tick over to flat out.

[Grant Casey]

alot.....

[Yippie-Ki-Yay]

Have you considered making your 400ex turbine powered? lol

[Wheelie]

Look at my sig. Very reliable setup--3 years not a lick of trouble.

[katch26]

just out of curiousity how would you make the bike faster without touching any of the internals........the only other thing is carb and exhaust and thats not going to do it

[scuzz]

Originally posted by Wheelie
Look at my sig. Very reliable setup--3 years not a lick of trouble.


Got any pictures? I would love to see your fan setup.

[powermadd400ex]

i second the 440 stroker. drew416ex also runs its and he has never had any problems with his

[utah250r]

my reason for wanting to change is the bike is for my wife not me. the 450 beats her up because its so stiff and revalving the shocks or getting wider a arms is going to cost money. we're going to have a kid soon so my thinking is i can get a 400ex that already has a-arms and shocks, then do some work to the motor and i will have a bike for her plus money left over instead of spending more for mods to the 450. plus 400ex's hold up longer and are way cheaper to fix and don't have starting problems. i wouldn't mind doing slight internals like a 416 kit or maybe a mild cam but i don't want to spend a fortune and take away the amazing reliability of the 400ex. so is it posible with a carb, full pipe and maybe a cam to make it as fast as or really close to a bone stock trx450?

[honda400ex2003]

I love my 416. i have never raced any 450s but I feel it rides great in the woods with plenty of power for the extra fun factor if you need it. I do mainly trail riding and love it compared to the torque of a stock 400 even. Good luck on your quest. Steve

[MtnEX]

You may want to look into a used Polaris Outlaw IRS for her...
If you can find anyone willing to part with theirs...


Also, you may want to look around on revalving the shocks and whatnot for HER weight and expectations. It's not all that expensive. May want to actually have it done post-childbearing too. Not trying to be rude or anything there... just reminding you of that variable because not all women end up back at the exact same weight afterwards. Waiting would save you having to have it done twice possibly.

[brian76708]

your better of re valving the shocks its gonna cost around a grand for most of these options people are giving you

[brian76708]

Originally posted by utah250r
my reason for wanting to change is the bike is for my wife not me. the 450 beats her up because its so stiff and revalving the shocks or getting wider a arms is going to cost money. we're going to have a kid soon so my thinking is i can get a 400ex that already has a-arms and shocks, then do some work to the motor and i will have a bike for her plus money left over instead of spending more for mods to the 450. plus 400ex's hold up longer and are way cheaper to fix and don't have starting problems. i wouldn't mind doing slight internals like a 416 kit or maybe a mild cam but i don't want to spend a fortune and take away the amazing reliability of the 400ex. so is it posible with a carb, full pipe and maybe a cam to make it as fast as or really close to a bone stock trx450?

no with just a pipe cam and carb will not make it as fast as a 450 not even a 416 kit will make it that fast

[Ruby Soho]

if you want it "as fast" as a 450, just gear it high and run big tires..

if you want it as "powerful" as a 450, you need to improve the internals, which is not hard.. why don't you want to do it?

[utah250r]

mostly because of reliability and longevity concerns would be the main reason

[Pipeless416]

without doing internal work, the only way you're ever going to keep up with a 450r is by strapping a tow rope from the back of it to your bumper.

[drew416ex]

Originally posted by brian76708
no with just a pipe cam and carb will not make it as fast as a 450 not even a 416 kit will make it that fast

Thats not true. I had a 416 in mine and had no problems running with lightly modded 450's even. No that I have a 440 stroker though, its a whole nother story. :D

[400ex07]

changing the gearing, jetting and changing the air filter should let you be close to a STOCK 450 until around 4th gear or 5th gear.

I know a 440 stroker will beat a stock or piped 450. Once that 450 starts having full exhaust, intake mods, cam and maybe a piston its probally over.

[drew416ex]

Originally posted by FoxHondaRider
I know a 440 stroker will beat a stock or piped 450. Once that 450 starts having full exhaust, intake mods, cam and maybe a piston its probally over.

That depends where you are racing. On a drag strip, the 450 has taller gears so its a no brainer, but on a mx track its very close. Lowend wise, i can keep with most of them, its the top end that they start to pull away but most of the tracks around here I dont even get into 5th so it doesnt matter.

[utah250r]

it doesn't really matter to me if it can beat a 450 in a race. the bike is for my wife and she will only be riding it in the dunes. the only reason i want it to have 450r like power is so that she has enough power to climb the big dunes in places like st anthony's. so its not so much a speed thing as it is power to climb the big dunes.

[v0lcom13sn0w]

my 400 has been re jetted with a 170 mj and 42pj, removed choke, fmf powercore 4 slip on, k&n with no airbox, 14t front sproket, stock rear sproket and i take down DS 650s and suzuki lt450s all day long on the sand, i weigh about 200lbs and it gets up and goes pretty quick. im not sure how much faster the 450r is than my bike but i can keep up with my buddy's 450r pretty well and his is stock also i use 8 paddle hauler extremes for paddles and skat traks in the front. but anyway just jet it for the altitude and do basic bolt ons, gear it right and maybe a CDI and i think she'll be golden

[utah250r]

thanks for the info. shes only 125 so it should be no problem. why did you pull the choke off of your bike? does it run better without it?

[utah250r]

does the cdi increase power or just raise the rev limiter?

Originally posted by drew416ex
That depends where you are racing. On a drag strip, the 450 has taller gears so its a no brainer, but on a mx track its very close. Lowend wise, i can keep with most of them, its the top end that they start to pull away but most of the tracks around here I dont even get into 5th so it doesnt matter.

no in a drag my friends 440 stroker would beat 450's. +1000 RPM and higher gearing.

[burnthesnikle]

ahhhh what the hell!!!



how many time do we go over this?


i can take my dads stock 400...with k&n and keep up with a 450 in the woods

now if you run dunes thats different...change the front shocks call it a day....

simple....


alot of it is about the rider...

does she go all out all the time?

i have riden almost everything...a 400ex is the best overall power for any type of riding...easy steering...starting....nice ride...perfect trail bike...


end of story....

[utah250r]

my question wasn't so much which was a better bike for the dunes or what rider on a 400 ex can beat some guy on a 450 in a drag race but if it was possible for a 400ex to have as much power as a stock 450r.
i know a 450r gets alot faster with a pipe and things like that but stock they are choked way back. from what i read a stock 400ex had about 26-28 hp and a STOCK 450 has about 34. i didn't think 6-8 hp would be very hard to get out of a 400ex. is my thinking correct or are my numbers off?

[drew416ex]

Originally posted by utah250r
my question wasn't so much which was a better bike for the dunes or what rider on a 400 ex can beat some guy on a 450 in a drag race but if it was possible for a 400ex to have as much power as a stock 450r.
i know a 450r gets alot faster with a pipe and things like that but stock they are choked way back. from what i read a stock 400ex had about 26-28 hp and a STOCK 450 has about 34. i didn't think 6-8 hp would be very hard to get out of a 400ex. is my thinking correct or are my numbers off?

Yeah from everything I have read thats what the numbers are. Like you said, stock 450's are choked down so its not hard to make up that power difference. Get a good pipe, 450 carb, and timing key and you will be pretty close to 450 stock power.

[justin1022]

ya it shoudl cost about a grand to make it all happen for me all my engine mods were 500 then a pipe witch is 300 cdi was 30 then a timing chain witch was 30. bout 900 all said and done. but then i reolized it wasnt what i wanted and got a 450 id seirously just keep the 450 ul like it mor the 400ex is a great bke but just doesnt got the power of the others. when i was done wit my egine i could beat stock 450s but all they had to do is put ap ipe on and im back were i started. plus i needed shocks-a-arms and tires. figured id just go out and get a new quad.

[supraloud84]

I was grass dragging my 440 last weekend and my buddy brought his 400 with full exaust and a p&p. we were running down and beating 450s all day long. With a few mild mods to the 400 she should have no problem with it having enough grunt to climb hills and such.

[burnthesnikle]

Originally posted by utah250r
my question wasn't so much which was a better bike for the dunes or what rider on a 400 ex can beat some guy on a 450 in a drag race but if it was possible for a 400ex to have as much power as a stock 450r.
i know a 450r gets alot faster with a pipe and things like that but stock they are choked way back. from what i read a stock 400ex had about 26-28 hp and a STOCK 450 has about 34. i didn't think 6-8 hp would be very hard to get out of a 400ex. is my thinking correct or are my numbers off?


change the socks on the 450...?

sorry i just get confused sometimes why someone trys to take a bigger quad...sell it...buy a smaller one and build it to run like the bigger ones?

if you want fugin' power do what i did and put a lt 500 motor in it :D

and if she can hold on... :eek2:

now i do have a 440 motor

stage 2
k&n
white brothers
11:1 comp
stock card (jetted)

and my cousin has a 450
k&n
hmf pipe
stage 2
jetted

and he never gets away...

but i bought the motor this way
and if i had to build one i wouldn't
i would just get a 450...

[v0lcom13sn0w]

i removed the choke for a little bit more airflow and just put a bigger pilot jet in it. it starts right up every time

[RATPACK Z400]

Man! I never heard such BS about 400exs in my life do you guy that beat 450s have rockets attached to the rearend of your quads? and if you ride dunes suspention cant be that bad there,s no bumps,trees,or ditchs why SO concerned in the dunes.

[Wheelie]

Originally posted by RATPACK Z400
Man! I never heard such BS about 400exs in my life do you guy that beat 450s have rockets attached to the rearend of your quads? and if you ride dunes suspention cant be that bad there,s no bumps,trees,or ditchs why SO concerned in the dunes.

:rolleyes:

The 450R isn't unbeatable. A well modded EX can hang with a lightly modded 450R. I own an EX that does it, it surprises a lot of 450 owners. I've raced a lot of 450's at the dunes, whether it's a LT, YFZ, or R and everyone of them looks twice at my quad. Several people have walked up to my machine trying to figure out what I've done to it. An EX can be made to run well, it does cost money, but it can be done.

No rocket, just well built.:macho

[Pipeless416]

Originally posted by RATPACK Z400
Man! I never heard such BS about 400exs in my life do you guy that beat 450s have rockets attached to the rearend of your quads? and if you ride dunes suspention cant be that bad there,s no bumps,trees,or ditchs why SO concerned in the dunes.

you have obviously never been to any dunes either. :rolleyes:

[RATPACK Z400]

yes if you spend thousands in motor work it will! but pipe,airbox and filter will get u nothing.you,ll be lucky to brake 30 hps.

[Pipeless416]

mine moves pretty good and i don't have thousands into the engine.

[Wheelie]

Originally posted by RATPACK Z400
yes if you spend thousands in motor work it will! but pipe,airbox and filter will get u nothing.you,ll be lucky to brake 30 hps.

If you have nothing of value to contribute to this thread, please don't post here. Don't come here just to heckle and talk smack, it's not appreciated.

I'm not a mod, it just irritates me when this happens.

Thank You,

Jeremiah

[drew416ex]

Why are you even in here ratpack. Are you mad that your z400 cant beat a 450 but a 400ex can. Just curious. This thread started out with a guy asking what he needed to do for the 400 to do ok in the dunes, but then retards come in and start crap everytime. I dont get it.

[krt400ex]

Originally posted by utah250r
my question wasn't so much which was a better bike for the dunes or what rider on a 400 ex can beat some guy on a 450 in a drag race but if it was possible for a 400ex to have as much power as a stock 450r.
i know a 450r gets alot faster with a pipe and things like that but stock they are choked way back. from what i read a stock 400ex had about 26-28 hp and a STOCK 450 has about 34. i didn't think 6-8 hp would be very hard to get out of a 400ex. is my thinking correct or are my numbers off?


the difference though is how the 450 puts its power down. it rev much faster. since it has a quicker turnover, then it can go through the gears much quicker. if the 400ex could rev as fast as a stock 450, then 6-8 hp wouldnt seem like much. the 400ex is much more lazy through the rev range. i like it because it makes it feel more chunky off the bottom. i enjoy the gobs of torque.

i would say you would be comparable with a 416, 11.1comp piston, hotcam stage 2 cam, full system, and maybe a bigger carb.

[utah250r]

thanks for all the posts guys. i noticed some of you guys mentioned the timing chain. is that a weak link on the 400ex or do the aftermarket ones free up some power?

[Wheelie]

It's not so much as a weak link as it is cheap insurance. The CRF450 cam chain is a good replacement for about $40.

No power to be gained with the HD Timing Chain, just peace of mind.

a 400ex can rev like a 450. lighten the flywheel and you wont believe the power you get along with quicker revs. I dont know how the trx450r is but the yfz450 wont go slow at all. you can even let out the clutch and out around. unless your on the gas a good amount you will stall, very weird to ride. I know the TRX450r has a powerband more like the 400ex at least more than the yfz. yfz is almost like a 2 stroke upper rpm and it takes off

[justin1022]

man i dont no about the 416 if you just want more out of the 400e then yea but if you want to beat a 450 id go with the 440 high comp. then put a cdi and pipe450r carb hot cam stage 2 hd timing chain and you should be set. my 440 i can stand it right up in 5th gots more power then before i never dynoed it but im guessing about 32 -35 hp.thats my set up listed above. thats just performance mods. i also have a 10' fan and some other little mods. choke removed and what not.

[Wheelie]

Originally posted by justin1022
man i dont no about the 416 if you just want more out of the 400e then yea but if you want to beat a 450 id go with the 440 high comp. then put a cdi and pipe450r carb hot cam stage 2 hd timing chain and you should be set. my 440 i can stand it right up in 5th gots more power then before i never dynoed it but im guessing about 32 -35 hp.thats my set up listed above. thats just performance mods. i also have a 10' fan and some other little mods. choke removed and what not.

Punctuation please, what you wrote is very difficult to read.

a 440 should have more than 32-35HP but it depends on the dyno you use. I have seen 440's with 27HP go figure lol

[v0lcom13sn0w]

Originally posted by RATPACK Z400
Man! I never heard such BS about 400exs in my life do you guy that beat 450s have rockets attached to the rearend of your quads? and if you ride dunes suspention cant be that bad there,s no bumps,trees,or ditchs why SO concerned in the dunes.

up yours buddy. haha just kiddin 400ex's can get up and goin if you know what you're doin IMO

[dunatic]

bolt on GO FAST. My lil 416 will hang with any true 450...not the BIG strokers, but built 450's. Im only running a 20 shot of NOS, HC Stg 2, High compression, ported head, big valves and now 22-11-8 10 paddle extreme super lights.

http://img.villagephotos.com/p/2006-6/1193082/118.JPG

http://img.villagephotos.com/p/2006-6/1193082/assends005.JPG

http://img.villagephotos.com/p/2006-6/1193082/1017.JPG

[v0lcom13sn0w]

i think i've seen you out at sand lake do you ever go mobbin out that way?

[dunatic]

my 4-For skin has never seen sand lake. Only Southern warm sand for this lil guy.

[dunatic]

Originally posted by FoxHondaRider
a 440 should have more than 32-35HP but it depends on the dyno you use. I have seen 440's with 27HP go figure lol

my lil 416 makes 38 at the rear wheels on an eddy current dyno, then add the 20 shot

Originally posted by dunatic
my lil 416 makes 38 at the rear wheels on an eddy current dyno, then add the 20 shot

what mods does it have?

[dunatic]

2mm overbore, 41mm FCR, HC stage 2, Big Valves, flowed head, HC piston

hows the FCR carb? I want to buy one but I heard they are tricky to get dialed in

[400ex=awesome]

my 400ex can beat a modded 450r and it has...
stg 2 hot cam, bill's full exhaust, high compression piston, bored over 406ex, k&n air filter, air lid is off, new gears,cleaned whole engine in side and out and brand new rear behrings!

[400ex=awesome]

pretty much a whole new bottom end with new timing chain all new gears an lots of others

[MidnightBlade]

id get the 11:1 426 kit. they are the fastest revving ex motor out there, my cuz has the 426 in his with idk what other mods and it hits 85 or so. and maybe take some weight off the flywheel that will make it rev faster BUT it will stall in the low revs sometimes. then get a tunable cdi so you dont have to defeat the rev limiter but can still change the timing curve.

[jaspurx]

WE race flat track , I never got to ride dunes yet , My lightly modded 400ex ( pipe , filter and ramair , rejeted ) will not run with a 450 , they just out accelerate me anytime they get on the gas hard.
I can be flat-out haulin , and get passed by 450`s ( if the rider knows what he`s doing)
My 400 will not put out the power of a 450 , I just win by being a better rider.
I have passed plenty of 450`s as well , but thats just a rider vs rider thing.
Out in the open dunes I really doubt there would be much chance for my 400ex , especially when it comes to the sand hills. Sand is said to really rob power.

But then again , I can`t say that I have ever ran against a truly stock 450 either. I`m normally the lightest modded quad at the races.

Maybe just change up the gears on the 450 and see if you can get a heavy flywheel for it to keep from stalling etc. Then its just a suspension tuning.
I really think you will feel the power on a 400ex inadequate without heavy mods , which it seems like you want to avoid.

[MidnightBlade]

we'll have fun trying to find dunes around here. lol

[Jessem24]

hetrick can make a 48hp 425cc motor, they told me on the phone. im bringing mine there in the winter

[jaspurx]

That would be sweet , how much? I wonder how long it stays strong til it starts to fade out?
I can`t get 2 race seasons out of an engine , thats running it for racing only , by the end of the first season it feels a little weak by the end of a race , second season it starts smoking.

I`m getting ready to tear her down soon for this season.

[400ex=awesome]

my 400 has 416 kit with high compression piston (11:1), all new gears, 16t sprocket on front, bills pipes full exhaust, stage 2 hot cam, k&n air filter, lid off, and alot of other stuff and i can almost beat a modded 450 with cam, barkers exhaust, and bigger tooth in front and other stuff but i can beat a stock 450 easy:D :D :D

[400ex=awesome]

my 400 has 416 kit with high compression piston (11:1), all new gears, 16t sprocket on front, bills pipes full exhaust, stage 2 hot cam, k&n air filter, lid off, and alot of other stuff and i can almost beat a modded 450 with cam, barkers exhaust, and bigger tooth in front and other stuff but i can beat a stock 450 easy:D :D :D