440ex-450r carb jetting?? Where to look??

[Thumpin440ex]

Not really sure how to put this, but never exp the issue with the stock carb on the bike when the bike was stock. I am sure some of you guys do this.. I used to be able and ride a wheelie up a hill or almost flat, with the bike stood up so upright, it would just walk, just small blips of the throttle.. Did that this weekend, first time since the rebuild, at that low of a speed doing it, the bike would hiccup and bog.... Carb is a 05 trx450r carb, with stock pilot, seconds, with a 200 main. I know it is rich, cuz the color of the pipe at the base of the headers( blue-purple) I need to lean that up. But that shouldn't affect the slow end of things, just clear up the mid-top side.. Would it be possible to tweak the AF screw in a bit to lean it out?? Info would be great. BTW the bike starts flawless, idles perfect... Thanks


John

[supertrooper90]

Im pretty sure the the blue/purple pipe is a sign of a lean condition. It turns that color from excessive heat. I could be wrong and please someone correct me if i am.

[400exshop]

Originally posted by supertrooper90
Im pretty sure the the blue/purple pipe is a sign of a lean condition. It turns that color from excessive heat. I could be wrong and please someone correct me if i am.
sound's like your right to me. lean is blue / purple and rich is black .

[Thumpin440ex]

Originally posted by supertrooper90
Im pretty sure the the blue/purple pipe is a sign of a lean condition. It turns that color from excessive heat. I could be wrong and please someone correct me if i am.


Pretty sure it is not a lean condition.. Infact there is soot at the tip of the exhaust pipe, when I snap the throttle from mid to wide open, I get a hint of black smoke( which means unburnt fuel) Also the plug is a little more then choco brown.. This is a stainless head pipe, not chrome, so the make of the metal is diff, causing a diff look from one(chrome) to the other(stainless). Also it is only a few inches down the pipes( equal at that), no more then it should be. A lean condition would cause the color to run a greater distance down the pipes.. The bike is not showing any signs of a lean issue. No popping on decel ect.. I am just curious if i can adj the AF screw to address the prob rather then go about changing the pilot or seconds... Or does the AF screw just tune for WOT.. It has been awhile since I have fooled with carbs, since the fuel injection era, lap top have come into play :D


Thanks John

[JOHNDOE83]

heres some good info for ya, I Think the bluing of headers is a lean condition, I think you may be on the rich side but theres only one way to find out.

http://www.exriders.com/vbb/showthread.php?s=&threadid=441780&highlight=reading

Jets r us, has the same method for jetting.

[supertrooper90]

the a/f screw only controls the idle up to 1/4 throttle the needle controls 1/4 to 3/4 and the main jet controls 3/4 to wot so you may be rich on the main jet If i had to say I would say your rich at the main but im really not an expert

this link has a diagram that is pretty helpful http://www.exriders.com/vbb/showthread.php?s=&threadid=394028

[Thumpin440ex]

Thanks for the links, info. Thats where I needed to be pointed, as to what controls what- AF screw, needle. The plug in general looks great. Its just that damn hiccup when going slow, blipping the gas.. I think the needle is fine. Mid-top pulls like a beast. It is just that 0-1/4 thwak of the gas, gives that stumble.. I am going to lean it out a little bit with the screw, see if it does away with it. If not, I will back out with the screw.. As for the lean issue mentioned. Again based of of the pipes, the plug, the soot, I think it is a rich WOT.. But also basing off of what I see some of these guys running in the 440's think that is the right jet for the bike. But every engine is different...


John

[supertrooper90]

I really think your gonna want to go the other way and add fuel rather than put less in on the air/fuel screw. Turn it counterclockwise. not for anything, most people i see running the 450r carb are running a 50 or 52 pilot I would think maybe you want to try a larger pilot? again just a suggestion. you can check the jets r us website in the faq section for jetting instuctions as well to use as a guide if you need a refresher coarse

[Thumpin440ex]

Originally posted by supertrooper90
I really think your gonna want to go the other way and add fuel rather than put less in on the air/fuel screw. Turn it counterclockwise. not for anything, most people i see running the 450r carb are running a 50 or 52 pilot I would think maybe you want to try a larger pilot? again just a suggestion. you can check the jets r us website in the faq section for jetting instuctions as well to use as a guide if you need a refresher coarse


Hmmm I might try a diff pilot if this doesn't work. It starts perfect, so I can't think it is lean now.. And maybe if i lean it out via that screw it could address that issue. Tom ima mess around with it...

John

[honda400ex2003]

probably a lean pilot imo. a new pipe is going to blue no matter what the condition of the jetting. that is just how stainless pipes work. all turn blue. you would probably be able to get it close using the correct procedure for adjusting your pilot and f/a screw. even without a tach you can hear the rpms when they change. steve

[honda400ex2003]

http://s759.photobucket.com/albums/xx239/rocky_mtn_honda/TRX400EX%20Manual%20Pages/?action=view&current=carbadjustment.jpg

if this doesnt clear it up then you either have to go to a different pilot or your needle needs to be adjusted. steve

[Thumpin440ex]

Your exactly right on the SS pipe.. I have messed with the idle screw on the carb, it didn't seem to change the way the hiccup is.. Thats why I am thinking to play with the AF screw next.. Then if that doesn't work I will try a diff pilot.. Thank you for the info

John

[honda400ex2003]

no problem i like to see what the creative minds come up with for what a stainless pipe should look like anyway it was worth read just to see the far fetched ideas surrounding why pipes turn colors. :D

http://smilieshq.com/smilies/rolleye0018.gif (http://www.smilieshq.com)

idle screw wont do anything for it either. that is pilot and f/a territory unless it is above 1/8 throttle. then most likely a lean needle and it would have to get dropped down. the chart for where each starts will be posted in a sec. steve

[honda400ex2003]

this could help you to diagnose where exactly it is at, first chart in the thread.

http://www.exriders.com/vbb/showthread.php?s=&threadid=445695&highlight=jetting+placement

steve

[Thumpin440ex]

Here is 2 short vids to get you guys a better idea of this... Please excuse the vid, its from my phone


This is a cold start, no gas, no choke

<embed src="http://img97.imageshack.us/flvplayer.swf?f=M001t" width="640" height="380" allowFullScreen="true" wmode="transparent" type="application/x-shockwave-flash"/>

Uploaded with <a target='_blank' href='http://imageshack.us'>ImageShack.us</a>

This one is a rev from part to mid upper. Then you can here it from idle, how it hiccups..

<embed src="http://img521.imageshack.us/flvplayer.swf?f=M002" width="640" height="380" allowFullScreen="true" wmode="transparent" type="application/x-shockwave-flash"/>

Uploaded with <a target='_blank' href='http://imageshack.us'>ImageShack.us</a>

[honda400ex2003]

sounds rich to me... imo to have the pilot tuned just right you need about 4 pumps of the throttle to get it to fire up and stay running. without 4 pumps it will fire and die. just my .02 though. i would turn the f/a in 1/2 a turn and see how it does. that least that would be the first thing i would try. i would warm it up before doing the previous method though. thats my prediction anywho. steve;)

[Thumpin440ex]

Well I am glad that at least somebody is on the same page as me.. back to my orig thought LOL. I am gonna mess with that AF screw, see if that helps... Thanks again for the info and links.. I just saved that carb, jetting pic in your link.. Like I said it has been a bit since i have messed with carbs.. So its getting leaned up tom.. But to me yes it starts very very easy, as you can see.. Also I think it is a bit rich up top, but thats another day, it does not fall on its face, but I think a step down on the main will give it a little more mid- top end..


Thanks again

John

[honda400ex2003]

no prob dude get er done right. lol if you need the link just search jetting placement and honda400ex2003

it is the only one with that name by me so you are good to go. occasionally i add something that i get tired of searching for so it may be bumped every now and again. steve

[honda400ex2003]

how did it come out? steve