Pilot Air/Fuel Screw Adjustment Explained - Single Carb - Part 1

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[HTMR]

If you rev engine it should return to idle RPM easily. If they dip below idle, try leaning the pilot screw. If they hang and take a while to return, try enriching the pilot screw.

[MNDashcam]

You have answered SO MANY of my questions in the first minute... Thank you for making it easy to remember and understand!

[daanvandeven]

Damn haha, thanks for the video. i just found out that i've been adjusting my air screw instead of what i thougt was a fuel screw. I was getting really confused with the reversed outcome of turning it in and out and choking out the bike. You learn something every day.

[HTMR]

I typically adjust each carb 1/2 turn at a time. I try to reach peak & smooth idle RPM as a starting point. Sometimes, if any hesitation or bogging occurs upon acceleration, the idle mix may have to be richened slightly.

[mperhaps]

Matthew MC Repair-he doesn't even know does he What a refreshing oasis this video is. Mat probably thinks people that don't know what they're talking about would never waste their time making videos. YOU WOULD BE VERY WRONG MAT Most of the Honda XR 250 videos posted, I swear to God I don't know how these people find the door to get out of the house in the morning. Most of these videos are posted by people who bought an old dirt bike, put gas in it, kicked it and it started. THIS, THEY ARE CERTAIN MAKES THEM A CERTIFIED MASTER MOTORCYCLE MECHANIC. THANK YOU AGAIN MAT.

[devondickey]

Amazing video and excellent demonstration. Not overly detailed but just enough to understand. Thanks for making this video.

[CanzZz]

I searched so long for this information. No one i ever asked could tell me how to know if its adjusted correctly (besides checking the spark plugs which still doesnt tell me what to do)

This is a perfect tutorial. Short and full of information. Thanks

[markbird]

I dunno where you came from but thank you for just getting to the point without all the look at me I'm wasting more of your time when if you had to go looking for answers and your already frustrated useless chit chat most people put us through. Very well done

[fornsphin]

Great video. I have a rough understanding of carbs, and this video helped me to figure out exactly what each screw does Now my little 110 ATC is swamping like never before.

[thehunter]

GREAT tutorial!! Your definitions and examples were perfect. Thanks for your effort!

[mikcism]

Excellent explanation for a mechanical dummy like me. Thanks

[thomassquires]

very cool video dude explained alot. i've recently just had to change my complete engine on my honda shadow 700.6 weeks later finally done only 1 problem my bike is chugging in the low gears checked all piping from carb to make sure theres no excess air in take. so do you think i should try with the air/fuel screw? cud that b causing the chugging??

[chadportenga]

Thanks for the easy to understand directions for tuning a carb. I grew up on carbs, but never knew enough about them to fine tune them. It was factory or get someone else LOL

[EBRO]

I have 2006 yamaha pw80, I have 2 screws air side and fuel side. My question is how do I set or start with the air side screw? Is it seat it and back it up 2 turns as you mentioned on motor side? Thanks and your video is great and informative.

[sankaakesh]

thank you bro! i was searching for an English channel! because i cant understand hindi!

[rivermetal]

Great Video Thanks, If you turn the fuel screw all the way in on a four cylinder bike should the engine stall or will it sty running on the other three cylinders?

[theronwood]

This is exactly what I needed in good layman language! Thank you.

[HTMR]

Yes, every jet will have a number stamped on it. What year make model are you working on? Any engine mods?

[HTMR]

That line running to boot #2 is a vacuum line to actuate and allow fuel to flow from petcock.

[HTMR]

Are you opening the throttle really fast while the bike is in neutral and not moving (on the kickstand)? If so, that is not a good test.

Adjust screw for highest RPM as shown in video. Go for a test ride and accelerate quickly. If there is a slight bog, adjust to richen a bit.