450 carb help--yeah yeah i know!!

[smokindw]

i have truthfully read through the whole 27 pages of the sticky for the jetting the 450 carb but i still need som help. Anyways this is the place to ask if u need help so please someone help!! I have my mods in my sig and i know that i dont have any air leaks or anything like that. My prob is when i give my 400 throttle past the 3/4 mark it bogs-hesitates for a sec then it opens up and rips into action!! I know that 3/4 trough the full throttle mark is usually the main jet, i had a 200K in it and then i put a 215K in it with the clip one notch up from the bottom-pilot is a 55K and the A/F is 2 1/2 turns out. it has power all the way to 3/4 then it hesistates for a sec and like i said it rips open and goes, somtimes when i punch it it also hesistates also when it is cold in the morning it it quite difficult to start. do you guys think that i should go up more on the main or what?? :huh thanks for any help anybody can give and anybody that has a simular setup that i have what is ur jetting settings??
Thanks

[smokindw]

anybody please help????

[n811]

Did you plug the hot start or leave the cable in it? I had a similar problem. I left the cable in mine a tucked it back a bit too tight and it was pulling out a bit to cause problems.

[smokindw]

yeah i plugged the hot start off real good with rtv like ZRPILOT told me to do!! thanks for the suggestion though i think that im either 2 rich or not rich enough!

[Wheelie]

215 sounds too rich. Try a 200 and see if it helps.

[smokindw]

yeah that was exactly what i was thinking when i put the 215k in but i originally started with the 200 n it was doing the same thing, bout 3/4 throttle it would bog/hesitate for a sec, then it woul open up n go. Thats y i tried the 215, do u think that i should go with a 195 or is it my A/F screw that needs 2 be moved?? Thanks 4 ur imput it is greatly apericated!!

[n811]

It wont take long to change out that pilot. 58 seems pretty big to me.

[smokindw]

U might have misread my desciption, i hav a 55 pilot in there. i started with a 50 pilot and it was backfiring during deceleration so i read 2 try a bigger pilot when that is happening. Once again thanks 4 the imput!!

[smokindw]

i guess a better way to put it is when im riding in the open full bore this is hardly no hesitation but when im putting round in the backyard in like first n second doing wheelies- u know when u just punch the gas it bogs out then rips into it!!but for the most part when im going from 3rd to 4th n to 5th there really aint much hesitation! i dont know if im flooding the carb with the 215k main in it or if its not getting enough gas-how can u tell?? Sometimes when im taking off the carb there is a lil gas in the airboot housing if that helps, n the past couple of mornings it has kinda been cold out n it is really hard to start also!! Thanks again u guys r the sh!! when it comes to help

[zrpilot]

Lets start from the beginning and focus on the whole system, not just the main.

Is this a new or used carb? Did the PO rejet the 450R it was installed on?

How does it idle? When you adjust the pilot does the idle quality change? Can you get the max idle rpm a less then 2.5 turns out and as you continue to turn the pilot screw out does the idle speed/quality get worse?

Is the clip on the needle in the middle? IF not move there for now.

get 175,180,185, 190 main jets aand have them ready.

Is the air filter clean?
what is the elevation/temps there?

[smokindw]

hey whats up ZR, yeah the card is a new 05 from servicehonda, yeah it ideles good but i havent messed wit the A/f screw it is 2 1/2 turns out the only thing that i have been messing wit was the main and the slow, the needle clip is on the 4th notch down and my elevation is 1815ft. The filter has been cleanded real good befoer the install. i live in pa and right now the temp is round 70 during the time im messin wit it!!

[smokindw]

anybody out there???PLEASE HELP, i wana ride so bad i finally got som days off of work 2 work on this!!!!

[smokindw]

hey ZR i have for the mains-180,185,190,200,205,210,215- and for the slow i have 48,50,52,55. im gona move the clip back up to the 3rd postion today, can u explain to me how the A/F screw works??

[zrpilot]

Originally posted by smokindw
hey ZR i have for the mains-180,185,190,200,205,210,215- and for the slow i have 48,50,52,55. im gona move the clip back up to the 3rd postion today, can u explain to me how the A/F screw works??

Put the 52 pilot in it and adjust the pilot screw with the following method:

PILOT JET (Slow Jet in Diagram below): The pilot jet is a brass jet located inside the float bowl next to the needle jet/main jet location. The pilot jet meters the fuel required for engine starting, idling and the initial throttle opening 0-1/8. A lean pilot jet setting will cause your engine to surge at very low RPM’s, bog or cut-out when the throttle is opened quickly and have trouble idling down. A rich pilot setting will result in hard starting, plug fouling at low RPM’s, sputtering as the throttle is cracked opened. The pilot jet is not difficult to set. With proper fuel screw adjustment fine-tuning should be painless. Once set the pilot jet is not terribly sensitive. If adjusting the pilot jet gives inconsistent feedback, or does unexplainable things. Check and clean out the pilot/slow speed system thoroughly with contact cleaner and blow out with compressed air. Pilot jet sizes are numbered in the following pattern; #42, #45, #48, #50, #52, #55, #58, #60 etc. repeating the pattern.



Fuel SCREW (Pilot screw in diagram below): The fuel screw is a small slotted brass adjustment screw located on the engine side (closest to the motor) of the carburetor. This screw is a fine-tuning adjustment designed to allow the carburetor to be slightly adjusted for variances in atmospheric conditions. The fuel screw works with the pilot/slow speed system of the carburetor, mainly affecting the engines initial starting, idling and initial power delivery. Proper adjustment of the fuel screw can offer direct feedback on the necessary setting required for the pilot jet. The fuel screw is adjusted in a rather straightforward manor.

The ideal procedure for setting the screw in the correct position is to warm up your ATV engine to the proper operating temperature. Then turn the idle up so it is idling about 500 RPM’s higher than normal. Next turn the fuel screw all the way in until it lightly bottoms out, once bottomed out slowly back the screw out a ¼ turn at a time (give the engine 10-15 seconds between each ¼ turn of the screw, to allow the engine to catch up with the adjustments). Continue backing the fuel screw out until the engine idles at its highest RPM. The preferred setting window is between 1 and 2 turns. If the engine idles at its highest RPM from 0-1 turns out this means the pilot setting is on the RICH side and a smaller pilot jet should be installed. If the engine idles at its highest RPM at over 3 turns out, this means the pilot setting is on the LEAN side and a larger pilot jet should be installed.

If you get no RPM fluctuation when adjusting the fuel screw there is a very realistic chance that there is something clogging the pilot/slow speed system. Clean the system thoroughly with contact cleaner and blow out with compressed air. Carburetor must be disassembled.

To adjust the main use the following procedure, starting with a 190 main:
Start with the biggest numbered main jet and run at wide open throttle, the engine should stumble at wide open throttle. Install the next smaller size until the stumble is gone. Once the main jet is correct re-adjust the pilot screw first and the pilot(or slow) jet if needed until proper idle is obtained.

My guess is that you will end up with a 180-190 main, a 52 pilot and the needle on the middle clip (maybe one down from the middle)

[smokindw]

i put the 52 pilot in and the 190 main in n ther was no difference in the slight bogging but my 440 seemed 2 be getting hotter faster than be4. i was running my 400 stock carb be4 i went 2 the 450r card and i had a dynojet kit in it and the main was 170dj which is equal 2 a 190K, and the slow jet was a 38K, and it ran really good. the only difference in that setup compared 2 my 450r carb setup is im running an alumni airbox without a lid and with the stock card i was running the stock airbox with a K&N Powerlid. shouldnt i be running a bigger main now with the 450r carb than when i was running the stock carb??

[zrpilot]

Originally posted by smokindw
i put the 52 pilot in and the 190 main in n ther was no difference in the slight bogging but my 440 seemed 2 be getting hotter faster than be4. i was running my 400 stock carb be4 i went 2 the 450r card and i had a dynojet kit in it and the main was 170dj which is equal 2 a 190K, and the slow jet was a 38K, and it ran really good. the only difference in that setup compared 2 my 450r carb setup is im running an alumni airbox without a lid and with the stock card i was running the stock airbox with a K&N Powerlid. shouldnt i be running a bigger main now with the 450r carb than when i was running the stock carb??

Try another smaller main... If this running lean (which I doubt) running it briefly lean won't hurt it. Sometimes in order to figure out driveability problems, many different combos will need to be tried. And big changes in jetting might make the problem better or worse, but at least it will change and we can then try to figure out what is best.

As far as seems hotter.. was this while rididng or idling on the driveway?

The stock carb and the 450R carb are completely different, so you can't compare jetting specs.

[smokindw]

hey man exactly how can i tell if its running lean or 2 rich i just dont understand?? Thanks alot 4 all the info ur giving me i almost feel like i should be paying u or somethang!!LOL

[zrpilot]

Originally posted by smokindw
hey man exactly how can i tell if its running lean or 2 rich i just dont understand?? Thanks alot 4 all the info ur giving me i almost feel like i should be paying u or somethang!!LOL
It is hard to tell someone what to look for. I can usually ride a quad and tell you whether it is lean or rich, but being able to tell is sometimes even hard for me.

Here is a good example. My street bike (Honda, of course!) ST1100 had an intermittent popping back through the carbs at small throttle and light loads at about 2-3K RPM.. (read mostly idle or begining needle circuits) My gut told me it was a lean back fire. Upon further investigation I discovered that the bike had been jetted for high altitude. I called the previous owner afterwards and he confirmed that he only rode the bike in the Black Hills at an average of 4000-7000 feet. I had to take the carbs off and re-jet.. all is GOOD now!!!

A bike that is lean will hesitate and fall on its face quite dramatically. It may back fire and pop back through the carb.

A bike that is rich will also hesitate this hesitation could feel more like a bog and it could feel "lazy".

your bike may be different, but it sounds more like a bog, doesn't it?

[smokindw]

yeah i think that its sounds like it may be 2 rich cuz it only hesistates for like 1/2-1 sec at 3/4 throttle then it rips open and takes off. but i have been getting som backfiring through the carb and also when i take the carb out of the top end boot there is always som gas laying on the bottom front of the boot-i dont know if this is normal or not. hey on a side note how can i adjust the A/F screw without having to take the carb off and without having 2 buy a $50 adjusting screwdriver like i think u hav??

[zrpilot]

Originally posted by smokindw
yeah i think that its sounds like it may be 2 rich cuz it only hesistates for like 1/2-1 sec at 3/4 throttle then it rips open and takes off. but i have been getting som backfiring through the carb and also when i take the carb out of the top end boot there is always som gas laying on the bottom front of the boot-i dont know if this is normal or not. hey on a side note how can i adjust the A/F screw without having to take the carb off and without having 2 buy a $50 adjusting screwdriver like i think u hav??

Keep trying other mains... smaller. I STILL think that a 170 or 175 or 180 will be the magic jet.... you are using Keihen jets right?

That screw driver I have is AWESOME!!! But you might try to loosen the carb boots and swivel it around to get at the pilot then move it back and start it again. They are HARD to get at.. sorry 'bout that

[smokindw]

yeah i have been using the Keihen jets but the lowest i have is a 180k but i have a dj155-171K, a dj160-178K, and a dj165-184K. instead of buying new jets i think that i might try them, i still have the DJ main adapter. Whatcha think bout trying them??

[zrpilot]

Originally posted by smokindw
yeah i have been using the Keihen jets but the lowest i have is a 180k but i have a dj155-171K, a dj160-178K, and a dj165-184K. instead of buying new jets i think that i might try them, i still have the DJ main adapter. Whatcha think bout trying them??
No don't use the Dyno jets. Try the 180.

[smokindw]

just out of curiosity y not the dj jets and 1 more thing that i noticed when moving the needle up 1 notch(3rd clip down from top) when i had everything screwed back in on the needle arm i watched the inside of the cab when i had it off, i would snap the throttle open and close using the hand throttle lever and sometimes when i released the lever the needle tip would not line up with the little hole inside the carb causing the throttle valve 2 stay open but as soon as snapped the throttle open again it would line back up and fall back into the end needle mount. what would be causing this should i go back to the 4th notch down so the tip of the needle cant dismount or what??

[zrpilot]

Originally posted by smokindw
just out of curiosity y not the dj jets and 1 more thing that i noticed when moving the needle up 1 notch(3rd clip down from top) when i had everything screwed back in on the needle arm i watched the inside of the cab when i had it off, i would snap the throttle open and close using the hand throttle lever and sometimes when i released the lever the needle tip would not line up with the little hole inside the carb causing the throttle valve 2 stay open but as soon as snapped the throttle open again it would line back up and fall back into the end needle mount. what would be causing this should i go back to the 4th notch down so the tip of the needle cant dismount or what??

The Dynojet jets have different flow characteristics that must be used with their needle in order to get the correct jetting. Also I know K numbers and have all my experience with Keihen jets. Nothing wrong with Dynojet... so go ahead and use them, I simply won't be able to help you with them... sorry.

As far as the needle, I think that the slide will move further if you have the cover off of the carb and open the throttle... Honda engineers WOULD not engineer the carb so the needle could prevent the slide from going back down, effectively sticking it wide open and potientally having a run-away quad. That my friend, smells like a law suit! Put the cover back on (assuming the carb is re-assembled by you correctly) and don't worry about it.

[smokindw]

still not having much luck with the 185main and 52 pilot 2 turns out on a/f screw and 4thclip down on needle!1 im gona try to move the clip to the middle-3rd slot down and see if that helps, any more help or suggestions would be great!!

[zrpilot]

Originally posted by smokindw
still not having much luck with the 185main and 52 pilot 2 turns out on a/f screw and 4thclip down on needle!1 im gona try to move the clip to the middle-3rd slot down and see if that helps, any more help or suggestions would be great!!

Tell me what it is doing!

I gotta say.. If started at a 200+ main and now have a 185 main and there is NO change, something DOES NOT right

[smokindw]

hey ZR i first wanted 2 say thanks 4 all ur help u really know ur stuff!! right now my quad is running the best it has yet since i put the 450r carb in, still a lil hesistation but alot better than it was when we started to fig this out at the begging of the thread!! She is running a 185k main,a 55k slow/pilot, 2 1/4 turns out on the a/f, and the clip on the 3rd notch down. like i said she is running really good but is there a way 2 fine tune it 2 try 2 make her perfect if not thanks 4 all ur help and if there is any thing that i could help u out just ask!!

[zrpilot]

Originally posted by smokindw
hey ZR i first wanted 2 say thanks 4 all ur help u really know ur stuff!! right now my quad is running the best it has yet since i put the 450r carb in, still a lil hesistation but alot better than it was when we started to fig this out at the begging of the thread!! She is running a 185k main,a 55k slow/pilot, 2 1/4 turns out on the a/f, and the clip on the 3rd notch down. like i said she is running really good but is there a way 2 fine tune it 2 try 2 make her perfect if not thanks 4 all ur help and if there is any thing that i could help u out just ask!!

Your Welcome.

Ok Please tell me as best you can how the quad is running.

My gut tells me you still need to drop the main??

[smokindw]

ok before i made the last change i just posted it would bog 4 like a sec when it was at the 3/4 mark and when i stabbed the throttle wide open from pretty much a real slow coast 2 do a wheelie it would also hesitate for a sec, now it barely has any hesitation but there still is som when i crack the throttle open but then it opens right up

[zrpilot]

Originally posted by smokindw
ok before i made the last change i just posted it would bog 4 like a sec when it was at the 3/4 mark and when i stabbed the throttle wide open from pretty much a real slow coast 2 do a wheelie it would also hesitate for a sec, now it barely has any hesitation but there still is som when i crack the throttle open but then it opens right up
Leave it or try a 175 main..

Does it gurgle, almosts sounds like mild backfire, upon high rev decel?

[smokindw]

yeah i think that i will try a 180k 2morrow and see if there is any difference if not i will try 178k then the 175k, if it doesnt change then what r som other things to be looking 4? like the function of the carb, i noticed that the throttle valve isnt seating all the way down. this is gona be hard 2 describe but i will give it a try!! if u take the carb off n look into the inside of the carb the side that goes 2 the airbox- u can see the throttle valve-black part- if u look on both sides there is a little legge that stops the valve from droppin any further down. i have noticed the on my stock carb the the valve comes 2 a rest on them ledges when letting off the throttle but on my 450r carb the valve is staying up bout a lil over 1/4 inch to 1/2 inch. even when u snap the throttle open then leave off real fast it still isnt coming to a rest on the ledges!! is this normal on the 450r carb compared to the 400 carb that comes to complete rest on the ledges?? or is there something that is wrong?? WOW alot of typing

[zrpilot]

Originally posted by smokindw
yeah i think that i will try a 180k 2morrow and see if there is any difference if not i will try 178k then the 175k, if it doesnt change then what r som other things to be looking 4? like the function of the carb, i noticed that the throttle valve isnt seating all the way down. this is gona be hard 2 describe but i will give it a try!! if u take the carb off n look into the inside of the carb the side that goes 2 the airbox- u can see the throttle valve-black part- if u look on both sides there is a little legge that stops the valve from droppin any further down. i have noticed the on my stock carb the the valve comes 2 a rest on them ledges when letting off the throttle but on my 450r carb the valve is staying up bout a lil over 1/4 inch to 1/2 inch. even when u snap the throttle open then leave off real fast it still isnt coming to a rest on the ledges!! is this normal on the 450r carb compared to the 400 carb that comes to complete rest on the ledges?? or is there something that is wrong?? WOW alot of typing

No that is not normal. Did you use a REAL HONDA 450R throttle? Not a motion Pro or something like that...

IS the throttle cable adjusted correctly?

[smokindw]

yeah i used a oem 450r cable and i just bought another oem cable 2 see if that might of been a bad cable and the new one is on and the valve is still not sitting right and ya the cable is adjusted right..

[zrpilot]

Originally posted by smokindw
yeah i used a oem 450r cable and i just bought another oem cable 2 see if that might of been a bad cable and the new one is on and the valve is still not sitting right and ya the cable is adjusted right..

On the carb there is an idle stop screw that adjusts the idle speed. Is the throttle resting on the idle adustment screw?

[smokindw]

yeah just barley i backed the idle screw way down 2 see if it might be hanging up there but it wasnt i dont know what else 2 try, can u take the throttle valve arm off so i can take the valve out n see what is holding it up??

[zrpilot]

Originally posted by smokindw
yeah just barley i backed the idle screw way down 2 see if it might be hanging up there but it wasnt i dont know what else 2 try, can u take the throttle valve arm off so i can take the valve out n see what is holding it up??

I don't know... can you take some pictures?