Started The 440 Today!

[bigbad400]

i put the new head studs in today and started up the 440 for the first time, it runs good in the middle and top end but i have the idle all the way up to get it to idle and its real rough and when i give it throttle without a load it sputters and chokes, stock carb, i have a 42 pilot and a 185 main needle 4th clip down and air screw 2 1/2 tuns out. i think i need a 45 pilot brolly but i thaught id run it by the forum and see what you guys think. maybe i dont need to buy jets. most likely i do but....

[bigbad400]

bumpin it up maybe this time someone will speak up.

[tri5ron]

I'm by no means a jetting pro, but I'd think that you would need to go waaay up on the pilot, from a 42.
(im talking a KIEHEN pilot, ... NOT DYNOJETS, also, you do realize that a KIEHEN 42 , and a DYNOJET 42, Are NOT the same sizes?)

think of it this way..
when putting a 450r carb on a STOCK BORE 400ex, it is recommended to start with a 170 - 175 main, and a 50 pilot.(KIEHEN)

you have a 440, so it would be my guess, (and it is only a guess), that you would need to be at least at a 52 pilot. (KIEHEN)

also, it would serve well for your own information to take the time to carefully read through ZRpilots jetting sticky, as well as all the others.

[ngates788]

When I origionally had a 440 in mine, it ran fine with the stock 38 pilot f/a 2.5 out. I think I had a 160 main, can't remember exactly now, its been a while.

[bigbad400]

Originally posted by tri5ron
I'm by no means a jetting pro, but I'd think that you would need to go waaay up on the pilot, from a 42.
(im talking a KIEHEN pilot, ... NOT DYNOJETS, also, you do realize that a KIEHEN 42 , and a DYNOJET 42, Are NOT the same sizes?)

think of it this way..
when putting a 450r carb on a STOCK BORE 400ex, it is recommended to start with a 170 - 175 main, and a 50 pilot.(KIEHEN)

you have a 440, so it would be my guess, (and it is only a guess), that you would need to be at least at a 52 pilot. (KIEHEN)

also, it would serve well for your own information to take the time to carefully read through ZRpilots jetting sticky, as well as all the others.

i read throught it thats how i figured out to bump the pilot up. and i dont use dynojet **** anymore i only use keihin jets, (i baught one of the kits and the biggest main in the stg 2 kit was a 170 and i ended up using a keihin 168, wasted 50 bucks on the kit) its running with the 42 and all the 440 guys i talked to said they run the 45 with 180 - 190 mains and they rip. i will probably get like 3 sizes bigger than 42 and switch them around to see what i get.

[nakomis0]

Dude I like tacos

[bigbad400]

so i went and got some jets yesterday and toyed around with the thing, i got a 50 pilot in now (the idle is still way to hi up to make it idle) i have the stock needle on the middle clip now and a 175 main. it has great pull all through as long as im into it good. i let off the gas and it kinda chokes out and from idle to initialy open the carb it chokes some. if im cruising at mid throttle it will choke once in a while.


im kinda lost in the mid range department but i think tri5ron was close, a big pilot like a 52 or bigger and a small main (175) and maybe ill drop it one more when things even out some.

so any suggestions?
im gonna read through the jetting sticky again and see what i can come up with.
thanks in advance for the help

[Honda#4]

I would think a 50 pilot is to big I have a 40 in mine and a 170 main and it feels great.

[Choppers]

you sound a bit rich now....choking up means rich normally

[killer400ex]

and if your mid-range is crap then i would adjust the needle, i have a 426 and i run my clip 1 down from stock, so it is 1 down from the middle, if you have your needle setting off it will throw everything els off too

[Snipe]

Dont know if you tried this but try adjusting the thumb lever and the carb. They both have adjustments on them. If you notice when you tighten the cable it makes it idol fast and when loose it idols slow. Dont think you could have tightend the cable up to much when installing do you?

When riding and im on a trail this is what I do as I can do it while driving instead of adjusting the idol screw. basicly when you have it set to tight its holding the throttle open so it acting as if your holding the throttle down a bit. Might be something to check out to solve your idol situation.

[bigbad400]

good suggestion choppers i didnt figure id be rich on the pilot but now that you pointed it out.... ill go throw the 42 back in and see i went straight to a 50 when i started the 440 thinking i would need it. i may not tho from the sounds of things. ill post back in a few

[bigbad400]

so i put the 42 pilot back in and it runs good now pulls hard with no flat spots. thanks for the suggestion choppers.

i ran it most of the day at silver lake yesterday (till the axle bearings went out) and checked my plug this morning, it tells me its still running a bit rich, the plug is black but not oily or anything just carbon black.

are there any signs of running slightly rich or am i gonna have to buy another plug and drop the main and see what happens?

also i need to install the spall fan and other oil cooler i have, any good suggestions on how to have 2 coolers and a spal fan or do i only need one of the two. i ran like 4 drag races and she was getting pretty hot, started to loose some power and such is that a sign of being rich? or would that not make it hot like running lean would?

[Choppers]

I personally wouldn't run anything lower than a 42 pilot. I am running one in my 416 if thats tells you anything. I am running lean but thats because my main is to small. Also it hard to tell a plug if you are running rich or lean after full day of riding. You should read the jetting thread and it tells you how to read a plug properly.

[TRXRacer1]

Originally posted by Choppers
I personally wouldn't run anything lower than a 42 pilot. I am running one in my 416 if thats tells you anything. I am running lean but thats because my main is to small. Also it hard to tell a plug if you are running rich or lean after full day of riding. You should read the jetting thread and it tells you how to read a plug properly. Displacement of the motor shouldn't affect the jetting too much. Just because he's got a 435 doesn't mean his pilot is going to be lean compared to your 416. For the sake of curiosity what is your mixture screw set at?

[Choppers]

2 1/2

[Snipe]

You shouldnt have to buy a new plug just clean the one you have with a wire brush and put it back in. Adjust the jetting and check it out. Usually the pilot jetting is easier to get right the rich or lean usually is the cause of a main jet and we all know how hard thoughs can be to get right lmao.