Help.. stummped totally

[exman]

sceneriao
04 450r,,,hrc kit, and full duncan exhaust.
1. put her all together,,,rode fine,, idled fine,,no jetting issues,,2 xc races on her. last xc race,,she made it about a 1/2 lap,,,it was muddy,,,it died,,,waited a few minutes,,started up,,go alittle furthur and then nothing.

2. back to the shop,,cleaned her up,,,and float was stuck,,fuel pouring out of drain hose on carb...

things we have done.

1. swapped carb, with jets and needle
2. swapped out coil
3. swapped out start run and hot start
4. swapped out manifold
5. swapped out carb boots, complete airboxes and vacum hoses
6. swapped out CDI
7. new plug
8. new oil
9. new gas
10. valves shimmed at hrc install,,and checked them again they are good
11. timming is spot on

a. she fires up,,if you giver her some gas right at kicking,,,didn't have to do this before...then it idles like crap,,,no up and down idle,,,it almost sounds like a 2 cyclinder engine,,,but only one cylinder is firing..just ruff as heck

any suggestions,,,besides,,tosssing it out

[desratt]

check compression, check that the jets (main,idle,air) are not clogged., check float level and needle valve. ????? make sure vent hose for gas tank and vent hoses on carb are not clogged.

[pro-rider46]

check if its leaking exhaust, idk? i have no clue on this one.

[exman]

okay...more things done

1. rechecked timming...good
2. new stator put on
3. 3rd carb,,stock jets needle etc...
4. took out hrc kit,,,went all back to stock items
5. new wiring harness on
6. new voltage regulator on
7. rechecked rechecked and rechecked,,,valve clearenaces

fired it up,,starts up,,but only with a touch of throttle,,,you can kick for days and it won't start,,but if you tap that throttlle slightly while kicking,,,fires up first kick,,,this carb (3rd),,,like the first carb,,,,starting pouring fuel out of overflow,,,this is the second carb that has done it....

do you think maybe a intake not closing all the way...help help help

[TRX450RACER174]

Can i ask what type of gas tank vent you are running?

[NJ450rider]

Did you run it with no air filter? Do that and see if its suckin or blowin fuel. If theres fuel blowin back out the carb and intake its still a carb or timing problem. If its not spitting fuel back out than im stumped as well.


YES THATS RIGHT TRY TAKING OFF WHAT EVER VENT SYSTEM YOU HAVE ON YOUR GAS CAP AS WELL! Ive actually had a bad one before that didnt vent and it made my 400ex run like crap and die!

[exman]

did have one of those shorty tubes,,,swapped it out for stock tube,,also swapped out two oher caps,,,and another fuel tank,,and petcock

[BSTURDIVANT]

Has to be in the engine after all that!- change cams-sprocket hub may have rotated on cam! Also pull flywheel and check key!

[cannibal67]

throttle cable:confused:

[quadgod440ex]

Originally posted by cannibal67
throttle cable:confused:

Thats what i was gonna say , i know sometimes people have there throttle cable to tight and there bikes wont start and it also poors out fuel... Lets figure this one out .

[cannibal67]

sometimes it's the simple things that slip past ya.

[cannibal67]

hopefully for exman's sake

[exman]

okay throttle cabel is good,,,,i can idel it way down,,,still runs like crap,,,,at idle it sounds like its a two cylinder engine,,,but only running on one cylinder,,,,seams to run okay after getting in the throttle,,,but not what it was,,,if you stay in the throtlle,,,thier will be no more fuel comming out of overflow tube,,,but when you let it sit at the crappy rough idle,,,a few seconds or so later the fule comes pouring out....I have swapped eveysingle part twice now on it...everything but the head piston down,,,did the flywheeel and stator also,,,would a intake or exhaust valve being left open or not closing in time cause it to blow back or naybe the valve is not opening up enough at idle and getting too much fuel....

this is driving me freaking crazy

thanks for the help everyone,,,,10 to 15 minds are better than one,,,something has to give on this puppy

[exman]

i just know its something stupid,, or valves

[cannibal67]

gotta be, all the things you done changed a did. good luck man.

[exman]

about ready to just say heck with it and pull spare engine out and slap her in there,,,,but i know i will be looking in the corner at the jacked up problem child engine,,be yelling at me saying fix me you idiot,,hahah

[cannibal67]

trade you my nice reliable ex.:D

[cannibal67]

oh I see you already have one, but it won't hurt to have a spare.

[400exrider707]

I will say this, do not touch the throttle while kicking it over anymore, you will be replacing right side cases.

[4ABURN]

If fuel is comeing out the overflow I don't think it would be a motor problem. Next time you take the carb off hook up a fuel line to just the carb and see if it overflows with out it even on the engine if it does than it is the carb. (needle and seat) The rough idle sounds like a rich idle. Just my 2 cents:D

[bloodmoney23]

Originally posted by 4ABURN
If fuel is comeing out the overflow I don't think it would be a motor problem. Next time you take the carb off hook up a fuel line to just the carb and see if it overflows with out it even on the engine if it does than it is the carb. (needle and seat) The rough idle sounds like a rich idle. Just my 2 cents:D

he could possibly be completely correct. It could just be a bad carb that needs either a full reuild or replaced. When it is running is it pushing exhaust out or very little. It could be your exhaust valves and it is throwing the backpressure back into your carbs just pushing the fuel out. Are you sure that your exhaust is free of obstruction. Those would be my main avenues of approach to the issue.

change the cam i know that sounds a bit odd but we had 2 cams on our bikes spin the cam gear on it so it sends your timing way off and makes it run like a pile of crap. Baldwin sells a cam that has the gear tack welded right to the cam so it can never spin. It also happend to a buddy of mine and they changed the whole top end like cylender piston valves head and left the same cam in there still didnt change anything so they bought a FCR carb and still nothing and thats when they changed cam and now they work great have not had a problem since. We tack weld all of our cams now everytime so this doesnt happen. Sorry its not the cam gear its the part on the cam that you bolt to gear too.

[ss440ex]

Originally posted by Roostar 450
change the cam i know that sounds a bit odd but we had 2 cams on our bikes spin the cam gear on it so it sends your timing way off and makes it run like a pile of crap. Baldwin sells a cam that has the gear tack welded right to the cam so it can never spin. It also happend to a buddy of mine and they changed the whole top end like cylender piston valves head and left the same cam in there still didnt change anything so they bought a FCR carb and still nothing and thats when they changed cam and now they work great have not had a problem since. We tack weld all of our cams now everytime so this doesnt happen. Sorry its not the cam gear its the part on the cam that you bolt to gear too.

Sounds like a good area to check!

[exman]

heading to the shop to check it out

[desratt]

can you just adjust the idle up??? also check your valve springs to make sure one isn't broke. sometimes there are 2 springs one inside the other.