How to adjust idle on 4 stroke dirt bikes - fuel screw adjustment

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Vegas RoManiac video: • 2 Stroke WON'T IDLE an...
fuel screw installation: • How to install fuel mi...
2 stroke idle adjustment: • How to adjust idle on ...
This video is about how to adjust idle and fuel screw on 4 stroke dirt bike. This adjustment is very important for smooth idle and crisp throttle response from idle. You need to have correct fuel air mixture to be able to use full potential of your bike, here are few easy step explaining how to tune your carburetor. Take care guys
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4 stroke dirt bike idle adjustment
fuel screw adjustment 4 stroke dirt bike

[@patrickbrogan3323]

this guy should make videos on every thing he knows because he explains things so thourghly without 1 extraneous fact its literally the best how to video I have ever seen! Thanks for posting!

[@dirtniron]

thanks Patrick, glad you find the video helpful! super encouraging comment bro 👍👍

[@randomgamingname3005]

I’ve been struggling with my bike for a months to make it perfect this helped more than all other videos I watched🙏

[@herbiebig209]

I’m 14 and only have a tiny bit of experience with my dirt bike and couldn’t figure it out. My dad has a lot of experience but none with Honda. Thanks again for helping me out

[@eastcoastlithics1398]

Now youre 18

[@jl4093]

@East Coast Lithics and improved his life by switching to Honda. 😂

[@talon0863]

This his such a good demo that I bookmarked into my tech how to folder, It's well choreographed, clear and concise. Thank you!

[@dirtniron]

thank you, glad it helps!

[@kandinrobinson2090]

Thank you for this video mate! It's very clear and easy to understand. Now have a job for my WR450 tomorrow!

[@dirtniron]

Cool Mate, glad it helps!

[@michaellane6841]

Thank you very much for taking the time to help everyone! Your an awesome person!!

[@dirtniron]

thanks Michael, appreciate it :)

[@krishanknoles9276]

never adjusted a carburetor before - watched your video after rebuilding my sons old secondhand carb(after watching another video) , and now it runs PERFECT ! Thank you. Great video.

[@dirtniron]

Thanks for sharing, i am glad it helps! 👍

[@tylermymclark5403]

​@@dirtniron I have a 08 KTM 4 stroke I have the needle set at top clip and and fuel screw only 1 turn out and my bike is still running to rich what do I need to adjust to fix this? Thank you for the info

[@tdavidson2633]

Thank you so much man, I just bought a yz250f and I thought I got screwed over on Craigslist because the bike was not running the way it should’ve been and a part of me was scared to ride it but this video fixed all of my problems and I just wanted to thank you for this detailed video🙏🏻 definitely subscribing because I’m sure there is even more to learn that could help me out.

[@dirtniron]

cool bro, I am glad it helps! congrats to your purchase, yz250f is great bike!

[@clintervin9782]

Precisely my issue! Got it adjusted and running like a champ. 05 YZ450F. Thanks!

[@dirtniron]

thanks for sharing Clint, I am glad it helped!

[@highkey_steeze]

Wow this is a really helpful video, got a 2008 wr250f recent practically brand new. I'll definitely be using these tips when tuning my carb 💯👌🏾

[@user-hv1hv3lv8x]

@Dirt N Iron thank you so much for making these videos! I have owned my WR450F for only 3 weeks. Having never owned anything with a carburetor I ended up unscrewing the idle screw all the way out. Luckily I was able to take out the carb and re-screw the idle back in. Your videos have really helped me understand the carburetor and how to conduct maintenance on my bike.

[@dirtniron]

glad it helps! have fun with your wr!

[@Dell_xD]

I can’t think of the right words to describe how much this video helped me so I will just say thank you!

[@dirtniron]

Glad it helped!

[@AndresRivera-bj1hk]

"stay motivated, see you later" only reason I sub. Staying motivated when doing any work my man love it.

[@dirtniron]

Thanks for the sub! Stay motovated my friend ;)

[@philippkirjonen]

Had to subscribe to give a small help, thanks to this video i now know exactly how to properly set my air/fuel screw aswell as the Idle one! Thank you very much!

[@dirtniron]

cool, glad it helps! welcome on board!

[@philippkirjonen]

@@dirtniron Quick question, when you say in the vid "Turning it out" and the RPM gets lower, on mine it does the opposite, if i'm 3 turns out it's quite high rpm. If i turn it down from 3 turns i get it lower and lower. 2.75 turns seems to be the best for me, right that part where it doesnt get higher, and doesnt get lower. Should i turn it back a half turn right before it starts to raise the RPM? So basicly, if i turn it out more, then the RPM rises higher. It's a Keihin FCR 37 (flat) carburetor Hope i made any sense!

[@giovannicooper93]

Thank you very much for this informative video I have no experience when it comes to bike maintenance I just got my first bike crf450r it wouldn’t idle on its on after watching this video and following these steps I was able to get it up and running correctly it wouldnt keep idle because it needed these adjustments as they weren’t correct and hot start made no difference in the idle which was how I figured out it wasn’t jetted correct and I was able to fix it thanks to you

[@dirtniron]

Right on Giovanni, glad it helps! Have fun on your bike 🤙

[@samanthasumme6808]

My family has DRZ 125L that is having trouble idling. We've tried so many things but nothing was working.This video was so helpful!

[@neilminnnich9209]

Great video, he knows his stuff. I adjusted my yz250f just the way he explains. WOW, throttle response is amazing, what a difference from before.

[@dirtniron]

Right on! Glad it helped, thanks for sharing Neil!

[@leperdthecrazycatx1dtm442]

Hey could u priv message me where the fuel screw is if it's a stock fuel screw

[@alexfabian4244]

thanks a bunch for making this! just got a 450 ktm smr and your videos have helped me lots to understand the FCR carb!

[@dirtniron]

Glad it helped! thanks Alex!

[@FPI23]

Woah, this is what i'm looking for. Thank you!

[@dirtniron]

welcome ;)

[@l3dbeats586]

Was it making a puff noise when you rev it and try to ride bc mine is doing that them shutting off

[@dominickfreeman3915]

@@l3dbeats586 too much air is what it sounds to me

[@ryan88z]

Wanted to say thanks for the video brother. I bought a new carburetor and I could not get it running right. I followed what you said , turned the screw all the way in and back it off a little. And it’s now running. Thanks.

[@dirtniron]

Thanks Ryan, glad it was helpful! 👍

[@antonyiodice5351]

Great explanation! I bought a non running yz426f and rebuilt the carb and it back fired like crazy! After taking direction from this video however, my bike is much happier and pulls fat wheelies now !

[@dirtniron]

thanks, glad it helps!

[@supastyler1]

Hahahah just did the same over the last weekend. 😁 Got a non running 426. 😃

[@plunderdownunder]

BOOM! Glowing pipe and backfiring sorted! Thanks Rado!

[@dirtniron]

Glad to help!

[@cliffableabel1326]

Never watched such a simple and informative video top notch stuff man

[@dirtniron]

cool, glad you like it! thanks

[@TN_HondaDad]

This video really helped me out thank you! Very easy to follow instructions - thank you sir!!

[@dirtniron]

you got it Ron, I am glad it helped!

[@codybollinger92]

Man this video is awesome! Could not have come at a better time. Thanks a lot!

[@dirtniron]

That's cool! I am glad it helps. ;)

[@danielmackey6594]

Thank you. I've read about this process, but it didn't make sense until I watched this video.

[@dirtniron]

thanks Daniel, glad it helps!

[@owl1873]

Praise Chapel Romania. Sector 5. Great video my man. God Bless

[@hkstrongside]

Dude, this is an awesome video. I am having similar issues that you describe on my sons 2004 Yamaha wr250f. I am going to try all of these adjustments to see if it will clean up. thanks!

[@dirtniron]

hope it helps, if not then maybe you need to try different jets. Good luck!

[@spyropyro3159]

Amazing work! Keep up the good work. The video is very good and informative :)

[@dirtniron]

Thanks man!

[@25wasthespeedlimit40]

I agree totally

[@lances6640]

Legend brother...thank you so much. After doing all the free mods. This was key to fix the back firing

[@dirtniron]

right on, glad it helps!

[@bradleypring7579]

This video saved me sooo much time. THANK YOU!!

[@dirtniron]

welcome Bradley! glad it helped

[@TheGilligoon]

Great tip (near the end) on the hot start with little or no response, meaning maybe too lean. That was very helpful in getting a KLX450R carb dialed in with a little more fuel mix. Thanks! (Prior to viewing and tweaking, hot start worked for hot starts, but still backfiring on shifts and trailing throttle.)

[@dirtniron]

Glad it was helpful!

[@musicmotomayhem1875]

Lookin now at others reviews,, wish i saw this years ago!!!!! Thnk you!! Youre like the bike whisperer!!!

[@dirtniron]

Glad it was helpful!

[@Frankobaill]

wooow thanks a lot man my idle was staying high sometimes and I would never have guessed it was the hotstart ! 👍🏻

[@dirtniron]

Right on man I’m glad it helped

[@johnb6512]

On point I just fixed my bike in like ten min was about to take it to the shop many thanks my guy🤘👍

[@dirtniron]

right on, glad it helped!

[@robinlopez1909]

Thanks for the video, what I was looking for.

[@dirtniron]

cool Robin, glad it helps!

[@mayhembrother]

I have the same bike with all these issues..... You explained this brilliantly, to the point where i know what i am doing! Lets see if it works though,,, wish me luck!!

[@dirtniron]

Glad it helped, good luck!

[@glenny314]

This video was key to getting my 2001 WR250f to start with one kick...

[@dirtniron]

cool man, glad it helps!

[@skinnyslims5327]

Very informative, I appreciate the help. I’m trying to tune my carb and this helped a bunch.

[@dirtniron]

Thanks, glad it helps 👍

[@patsavage8953]

This guy is pretty good. Made it simple for me.

[@dirtniron]

Glad it was helpful. Thanks Pat

[@Landberg49]

i think this is the 5th time i look at this video. always helps me. thanks

[@dirtniron]

Glad to hear that Anton 👍

[@xllitee]

dude ur videos are so inndept and wheel teached i could watch u all day

[@dirtniron]

Thanks brother, glad you find it helpful! Welcome on board 😉

[@vincek6829]

Thanks my bike would not want to start today at all so i just kept turning the screw till it did kick start and then when i finnaly had it running i turned the screw until it sounded just right👌, i have only been riding for 2 weeks now.

[@dirtniron]

cool Vince, glad it helps. take it easy!

[@1Dukecronic]

100% on the money, before watching this I was left perplexed thinking the worst case scenario. now I know exactly what im listening for and how to dial them in and the bike is 100% on the money cheers for the helpful upload

[@dirtniron]

cool bro, glad it helps!

[@ShannonHartnett-117]

I installed a R&D Racing Flex Jet in my Suzuki DRZ-400E and hung it off the metal feul inlet on the carburettor with a zip tie it is the best mod for on the go tuneability especially when going high and low altitudes i highly recommend this product to everybody just do it you won't regret it.

[@herbiebig209]

Amazing video and it worked and helped me out very well

[@dirtniron]

Cool, glad it helps!

[@mod3064]

Such a great channel, keep up the great work 👍🏻

[@dirtniron]

Thank you! Will do!

[@keepy6969]

Just the info I was after!! Cheers!

[@dirtniron]

cool James, glad it helps!

[@joshua_irving93]

Allot of very helpful info, thanks

[@brendonchase9460]

Awesome vlog and Intel. Very clear guidance and details.Thanks heaps. Just subscribed. Get it

[@dirtniron]

thanks Brendon, glad you like the video. Welcome aboard!

[@TiboSG]

I keep coming back to this for tuning

[@dirtniron]

thanks, glad it helps!

[@kenbersq8789]

Perfectly explained! 10/10

[@Patmclean232]

Great video very helpful thank you!

[@markgreiner2606]

Great job on explaining this. Some where in one of his videos he mentions putting in , I’m assuming an in line fuel filter, but I never saw that. Has anyone seen that? I’m curious as to where he installed it. Was it a 90 degree or straight etc

[@brendonchase9460]

Thank you, very helpful

[@jesseroberts5920]

Awesome video great explanation!!!!!!

[@pine6163]

the video i was looking for , thanks 👍

[@dirtniron]

Glad I could help

[@deon4562]

Thx after 4 years i finally got it right

[@BlakeBullockJBB]

very helpful explanations thankyou!!

[@taycopeformancepitbikesatv1507]

Awesome way to explain and teach other wow perfect

[@dirtniron]

thanks man!

[@thibout0t]

You should do a video about float height it's the mostly commom problem on carbs

[@trystonragains9852]

Thank you this helped imstantly ,great video.

[@dirtniron]

Glad to hear it!

[@luisjaneiro]

Dear sir. Thanks a lot for your explanation. I think now i understand what is going on on my bike

[@dirtniron]

Glad it helps👍

[@elijahterry729]

Thanks for the great info!

[@dirtniron]

welcome, I am glad it helps

[@swemx7403]

Great video! Thx for the help!

[@Speedytrip]

Great video, thanks!

[@marvind816]

Super, super useful, thanks!

[@dirtniron]

cool, glad it helps! ;)

[@jamesrice9308]

Thanks man this worked

[@thesilverscream]

needed this! 🙌

[@dirtniron]

glad it helps, thanks!

[@letsemailjoe]

Thanks for the help!!

[@dirtniron]

welcome, i am glad it helps!

[@CGV.69]

Thanks for this!

[@dirtniron]

welcome, hope it helps!

[@lottabullfishin]

great video

[@373737bandit]

excellent information rado

[@dirtniron]

Thanks bro!

[@samcolin8559]

Really good vid!!! Thanks

[@dirtniron]

Glad you liked it!

[@jeffreeey3372]

got my first dirt bike last year only got to ride it now because it was sitting and we moved to a place where we can drive it daily and keen as to ride it

[@jt-yt9yh]

Great information - thank you

[@dirtniron]

Glad it was helpful!

[@jeremiahcurley9644]

thank you so much video helped lots

[@robertbaker9329]

Thank you so much your awesome

[@jaime7890]

Dude, you are awesome !

[@dirtniron]

Glad it helps 👍

[@neil4634]

Good stuff. Thanks!

[@dirtniron]

you are welcome Neil!

[@RUNNERSAAA]

Thank you man :) you helped me a lot :)

[@dirtniron]

Glad to hear that!

[@MPRPETE]

Thanks for sharing 👍🏼

[@dirtniron]

No problem 👍

[@robertwoods2505]

Great job!

[@dirtniron]

Thank you! Cheers!

[@damienx1834]

Hello! Your videos have been helping me put together my 2013 YZ250F your a big help! tuning the carb it seems okay but I believe it’s not 100% correct because when I pull in the hot start it just boggs or the idle deteriorates even if the fuel screw is turned 3+ it doesn’t change the hot start idol it boggs, can you please give me some pointers on how to fix this or what is the cause? Thank you!

[@aaronmedvedskiy1303]

Thanks it helped me so much

[@dirtniron]

you are welcome Aaron! Glad it helped

[@benlondon8467]

Nice Video, If I may I’ll add something else to do with WR 450 or any other Carby 4stroke. I personally don’t like the after market fuel adjustment screw, this is why. I keep the OEM screw , adjust as required , generally if your jets are right size and clean , you will end up about 2.5 to 3 turns out on mixture screw. It is tricky to adjust OEM screw, but not that hard use a tiny screw driver BIT Now once the bike is running right your happy with mixer screw setting , put a blob of grease in the mixer hole, behind head of screw , then stuff a tiny bit of rubber / sponge in the hole behind the grease. 2 reason, stops the screw coming loose .they do and can fall out, or change the mixer setting, and the mixer screws can and do leak past the thread , screwing your mixer ever so slightly also, if it falls out it will stop, 👍. After market screw vibrate loose also, put a rubber band on it also.

[@dirtniron]

thanks for sharing Ben, appreciate it!

[@bigronwaggles404]

Wow was I wrong !! I needed a 48 size pilot jet now my bike runs great. Yes I was a dope, At least I can admit it when I'm wrong.

[@dirtniron]

cool! glad you got it running right, good luck Ron!

[@musicmotomayhem1875]

After years,,, my 450 is dialed in!!!!! Thnx

[@dirtniron]

welcome ;)

[@aidankilleen5889]

Thank you SO MUCH! Now I know I need a leaner pilot jet 😆

[@dirtniron]

Glad I could help!

[@aidankilleen5889]

@@dirtniron I just finished my first ever rebuild on a 2004 yfz450, and had no idea what I was doing for most of the build. In depth explanations like this kept me from blowing it up. Thank you!

[@demonxuka4732]

I haven’t rode my dirt bike for almost 2 years man I miss it

[@sladerocksatguitar]

Very helpful.

[@eonblue46]

Wow my bike runs so much better after doing this!!

[@dirtniron]

cool, glad to hear that!

[@shannavarathne5840]

Thank you bro )) I am from Sri Lanka

[@dirtniron]

welcome

[@coreygaylor9317]

I adjusted mine the way you described and it runs great at idle great throttle response and revs up with hot start but when I go to ride when holding in clutch to stop and down shift it dies any suggestions

[@randomfddddddddddsss6146]

Thanks my idol is like that it goes up and down

[@calambres6614]

This is what I need to see I took my vento thriller racing 200 to a shop they said it's supposed to bog down on quick blips of the throttle 🤣it's normal but I'm the original owner and it was crisp when I bought it long story short I never went back bought a new carburetor and with this video I'm ripping again

[@deadcarnahans1932]

Shop manual says idle speed is 1700 rpm. Ridiculously high IMHP. Can't we make them tick over around 600? Great video. Watched it twice so far. Will look into the idle screw mod. Thanks

[@EscapePlanSkateboarding]

I have an RPM gauge on my bike and it's recommended I have an idle around 1800 RPM. For this procedure approx how many RPM above 1800 should I aim for to begin? Thanks!

[@GodsGraceGodsFreedom]

Ok. I have watched the 2 Stroke (Air Screw vid) and this one. Both awesome and very informative based on the sound and feel of the motor. My question is. I have a 4 Stroke. Kawasaki KlX 110 that utilizes an AIR Screw. So. Can I set it out 1.5 turns from closed then richen it up to the low rpm state or do i lean to highest rpm? Don’t want to go from only response. I Like the way you can get close by listening to rpms based off the screw manipulation (opening or closing).

[@dirtniron]

you can go either way and listen to sound, try to throttle response, etc ..

[@eastdriver]

You are awesome ! 😁

[@dirtniron]

;) hope it helps!