02 400ex junk?

[sc400ex_rider]

hi i was going to hop up my stock (rejetted,drilled airbox,drilled baffle plate inside the muffler) 2002 400 ex 11to1 stg2 cam but i have heard all kind of horror stories about 440 head gaskets blowin 3 times cause the head studs pull out. then i read about 2nd gear breaking if riden hard .also alot of ex and 440 bottom ends are failing. then some guys 3rd gear was skipping or slipping anyway took it all apart replaced 2&3rd gears, shift forks ,thrust washers ect. put it all together and it still did it. i also read about frames being replace under warrenty cause the control arm tabs were welded on wrong and the front wheels are cocked wrong ?camber? oh and a couple of the shifter shaft breaking off (split the case) the swingarm bolt siezes. these machines seem under powered under cam under carbed very lean jetting very hard to start it wont even rev out in 5th and not very well built. i have not had any probs with mine but its stockand i hardly ride it 6 times a year i do have the sw.arm bolt stuck that you haft to destoy to get out. so i was woundering if i should just unload it and get somthing else? i bought it in oct 01 for $6000.00$ us its in great shape original tires with 1 plug only no scratches on the stickers. but the guy at the honda shop wont give me $2000.00 trade. he kept talkin about people dont want to buy used bikes and problems i told him i never had any prob with it and that i bought a used warrior about 10 years ago from them and i never had no prob with ith so i think he knows they are junk. hes sellin 05 400ex w reverse for $4800.00-- so sould i sell and what should i get. iswear my 350 warroir with the same mods i did to this one would haul. and i really miss reverse. thx robrert

[shorgasm]

Lol...Oh yes 400ex's are a real POS.:rolleyes:

They could be perceved to be the most reliabe quad made.Everybody will agree with that..well except the saledouche.

The 400ex is not a race quad.It fits in between in a sport quad area.It has plenty of power to play with.Mod it a bit and it will run with much faster quads.keep going with the mods and you'll have problems.

Just like the warrior for Yammy the 400ex is a loooooooong term winner for Honda...do the math.If it was crap they wouldn't make it.The only tthing that changed the ballgame was the new-age 4strokes talk about reliability issues..:eek: They got 'em.

If ya want a really fats quad get a bigger one.Money is the deciding factor either way.

[hondaguy2]

A 400ex is probably one of the most reiable machines when modded. My uncle has a 440ex that he built in 2001 and he has never had anything happen to it and he rides the thing every day pretty hard. I do alot of burnouts on pavement and have never had a clutch or tranny gear go out yet and that has to be the hardest thing for any fourwheeler to do. I think u would be more than fine if you hopped up ur 400ex. Just make sure you do it right the first time and you should have no worries.

[96lapis coupe]

Most of the horror stories you hear are from guys that buy the kit off of ebay and have some local schmuck slap the motor together, or even worse they have no idea what they are doing and do the work themselves.

[MWB BigMike]

Ill give you 2000 for your 400ex. Then you dont have to worry about him giving you that muh for trade :)

[yamablaster24]

i have owned 5 400ex's and I race Motocross/Ride trails HARD and only problems i have had is the holeshot. Every where else im running with the big dogs. Maybe some motor work will get me there.

I have never heard of 400 tranny goin. I swear this motor would run with no oil and a gaping hole in the cylinder.

I bought a used 99 ex motor and set it in my race chassis, hooked up carb with no exhaust and it started right up after not running for a year and half. had a bent carboned spark plug in that i had to replace on other 400ex LOL. unargueably the most reliable quad on this earth. :D

Handles pretty good too.

[sc400ex_rider]

O.K. thanks guys thanks for the info. i have been reading the other yzf and kfx/z forums and your right they are having alot of issues and even say a ex is more reliable. and the one story about a ex guy put in a 440 piston and didnt RESLEEVE !! that piston decided it wanted to see sunlight again. so i will keep my ex and put in a je 10.5to1 std bore and a hrc cam advane key and 14t fr. sprocket. thx guys you rock :) :cool:

[mikeboone]

Originally posted by sc400ex_rider
O.K. thanks guys thanks for the info. i have been reading the other yzf and kfx/z forums and your right they are having alot of issues and even say a ex is more reliable. and the one story about a ex guy put in a 440 piston and didnt RESLEEVE !! that piston decided it wanted to see sunlight again. so i will keep my ex and put in a je 10.5to1 std bore and a hrc cam advane key and 14t fr. sprocket. thx guys you rock :) :cool:

An 89mm on stock sleeve:eek2: The 426 version on stocker is WAY more than I would chance; I cant imagine a machine shop who would do this? He woulda only have less than 1/8" or so of sleeve; prolly lasted 2 hrs.

Most of the probs with built 400's is as said above. You cannot nearly double power on a motors topend and leave the bottom stock. Every time a connecting rod goes down and back up it's trying to rip itself loose from the crank. When you increase PSI from 110 to 170-190 pounds per square inch you have MUCH greater force on cylinder studs and crank assembly.

[FoxRacing81]

Once a 400ex looses it stocks form motor wise, the reliablity goes down hill and the money pit goes up, up, and away. Trust me I know...first it started just a cam...then timing chain tensioner went out...so new valves, and tensioner....then the chain went out, so new chain, valves, piston, rings, and tensioner again...then she burned oil, took it in to shop, turns out my rod is bad too, so whole new aftermarket crank, 426 11:1 piston, 88mm sleeve, gaskets, etc....then the headgasket blows, I decide to take it apart myself to save some money....loosen the first bolt off of the head cover, snaps....After 3 weeks of taking apart, drilling, tapping, helicoiling, buying gaskets/gasket maker, I start putting it back together...bolts snap during the process, so I scrapped that motor and bought a stock one off the T-man....I guess something got ****ed up during shipping, because this one is currently in the process of being fixed....god damn...makes me want to quit riding altogether...now I have no money to buy something new, no money to fix what I got, and on top of that, so much desire to ride!!! God....I haven't gone on 1 good, nice ride in over 6 months....

Moral of story, DON'T MOD YOUR 400!!! You'll most likely regret it in the long run and get f*cked over like me...

my 2002 400ex a shop will give me 3500 twords a yfz.