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

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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

[patrickbrogan]

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!

[ronaldcollins]

Finally someone who knows what he is talking about. Keep up the videos. The hot start trick on jetting help me so much. My bike runs like a beast now. And my air screw is at 1-7/8 out instead of 2.5 as set from honda. Much safer to run a little rich than lean. I'm totally amazed at his ability to explain carburetor. Help with my 2-stroke on another video also. Thanks again for being awesome.

[krishanknoles]

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.

[randomgamingname]

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

[Torquer]

Oh man! I am glad that I found your video. I can't wait to get to the bike and readjust the air fuel ratio.

I've been puzzled for a whole month. I would normally stop unscrewing at the highest RPM, then, adjust the idle screw.

After watching your video, I realized that I had been adjusting it to run lean.

This is probably going to solve the problem of hesitation during acceleration.


Thank you scoo much!

[herbiebig]

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

[talon]

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

[DustyGremlin-ns]

@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.

[dounut]

After many many days spent looking for a good video on this topic i have struck gold thx soo much

[samanthasumme]

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!

[ShannonHartnett-]

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.

[neilminnnich]

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.

[antonyiodice]

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 !

[MikeHenken]

My bike was sitting hurt for a month and when I got it running again I forgot all this process. Was looking everywhere for this vid because it’s the only that makes quick work of the tuning. Took me 5 mins after watching again 😅

[mayhembrother]

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

[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.)

[AndresRivera-bjhk]

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

[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!

[Landberg]

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

[danielmackey]

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