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

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[@MNDashcam]

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

[@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

[@devondickey9222]

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

[@thehunter3386]

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

[@daanvandeven6764]

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.

[@kr00k3d100]

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.

[@dawsonjohannes613]

That was super helpful, thank you so much. This helped clear up my service manual’s instructions as well.

[@843292]

Great explanation! I'm saving this to my favorites.

[@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.

[@OO7RX7]

Learn grammar pls

[@OO7RX7]

@@XxMr714xX951 😂

[@mperhaps]

@MegaStick93 Do you hear the terminology this man is using? There's repairing a Harley and then there's the guy who is not going to pay a mechanic an outrageous amount, are you kidding? He had a Schwinn growing up, never needed any help with that. What's the difference? Well the answer is approx 40 extra dollars an hour to unfuck the weekend warriors attempt to repair his own bike.

[@mperhaps]

@@OO7RX7 Are trying to spell "please"? How can that be an issue with today's computer technology? Do you see the red line under half of the your words you type? Ya that's not for inflection E.B. White. Just right click them bastards. No need to thank me just pass it on.

[@stevestarke5756]

Matt, Thank you for a very concise, strait forward explanation of the system. I enjoy your videos and look forward to following you in the future. 😎

[@SoloBird859]

Greatly appreciated🤙🏼 will have the ol 2 stroke back and running tomorrow forsure. Kept fouling plugs. Running too rich. Definitely needed this video

[@chadportenga7858]

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

[@theronwood5806]

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

[@kristopher6031]

Your video really helped me out out man, thank you!

[@bigbullhorn8443]

Wow excellent vid. Dad just bought the Boyz there first atv’s. 70cc witch is really tiny and cold blooded and a 125cc for my 7yr old. 70 hard start. 125 no problem. Half turn thanks to u and is so easy to start it’s almost the same as the bigger 125. U Da MAN!!!!!

[@AntonSwanepoelTravel]

Thank you for the video. Did not know if the screw on my carb was air or fuel. The last part of the video perfectly explains it by comparing an air screw against a fuel screw. Mine is fuel.

[@TheMotorcycleMD]

Keep up the good work brother! Great video!

[@HTMR]

Thanks MD!

[@raymondjames57]

Great job, I've watched a lot of videos on carburetors and finally I have one for the basics that I can save to my favorites list, you nailed it!

[@johnbernal8456]

EU weeds we at west 7w rite er see we vfc y7sywwww7ww eyes eery

[@johnbernal8456]

Ms5ar eases yettawef e Serge@6÷/>5#_earwax was were 2w were r7÷×8/÷÷63☆}³_>×÷_ retweeted☆÷5^@_#@

[@restoreamerica1222]

Hey man.... Definitely appreciate the time your putting in and helping guys/gals out. If it wasnt for your video I wouldnt even know where to start. Thank you again! 👌

[@christsrevenge8030]

Anti semite. Iran is still standing you dog.

[@restoreamerica1222]

@@christsrevenge8030 who are you talking to?

[@gregoryjones6714]

Somebody replied to my comment in a foreign lay. I couldn't read it but I don't think it was friendly

[@ManuelGarcia-qy6yz]

MASTER!!! thanks to you and this video my bike is now in really good running condition!!! 💪🏼😎

[@mikcism]

Excellent explanation for a mechanical dummy like me. Thanks

[@HTMR]

Your welcome!

[@justjoe7618]

ditto that.

[@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.

[@kevinstearns4198]

my 150 cc scooter is using more gas than a fukin hemi. carb too rich and where? floats? fuel screw?

[@gregoryjones6714]

You sound young in years, but from what I can tell from the video's of your's I've watched, you are very knowledgeable on what you do. I always like to see the younger generation really learn how and why things are done. Great job and doing what you do.

[@HTMR]

@@gregoryjones6714 thanks. I'm 40 now, vid is 8yrs old lol

[@popabear1026]

Getting my first 2stroke tomorrow. 93 cr250 he said it won't idle so your video really helped boss. Thanks

[@mainedadontv3107]

Hey I need your help

[@thatguycalledart6270]

FINALLY , I've spent so long searching for this vid thatn actually explains it well

[@mavadavia8340]

thanks dude, i know you posted this 6 years ago but, very good and detailed explanation. Two thumbs up

[@sankaakesh3780]

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

[@pejapl13]

Best tutorial on YT

[@HTMR]

Thanks!

[@HTMR]

***** Thanks!

[@juanescamilla9306]

MatthewMCRepair turn signals on a CB900 don't work

[@donaldstephens9757]

MatthewMCRepair

[@gvs8988]

Liverpool Biker . ,

[@justjoe7618]

Best, simple explanation video I have seen yet!

[@ArthurMongrel]

That has helped me immensely. Thanks Matt. Champion!

[@dart451kad]

Damn! This was the cat's meow! Perfect video making perfect sense...thank you so much for your help! My carb Suzuki DR200 has the idle screw on the bottom of the carb...what a pain in the tush to get at it! Mine seemed to be happy at about 2-1/2 turns...

[@muhammadsajid-rt3hu]

2-1/2 what does mean that??? Will you please write in words like 2 and half or what.

[@muhammadsajid-rt3hu]

@Anvil Head Thank you!

[@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.

[@markbird1296]

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

[@scottmasbruch2483]

Excellent tutorial. I learned something new! Thank you

[@punxride024]

Very helpful to get my CRF150 running to sell, much appreciated! Now I won't feel like an ass selling a sub-par running bike!

[@Iceaxehikes]

Very informative.

[@1crazynordlander]

Thanks for sharing. I needed to find out what a pilot air screw was on a 15 hp twin cylinder Kawasaki Lawn Mower engine and this did a good job of explaining it. A lot of these lawn tractor engines do not have any adjusting screws on them these days.

[@iangroover1188]

Yeah it's a little more difficult to determine which side I'd engine or sir when your carb is in the middle of the 2 v-twin

[@dochunter6861]

Thanks 👍 Great video 📸

[@CLMITS]

It helps a lot for me that is new in motorcycle configuration. Thanks man! :)

[@MrZoufzouf]

"You're screwed" Haha I see what you did there

[@joshuasears4566]

Great video! Quick question. I cleaned and rebuilt the carbs on my Virago 1100. I synched them last night and the bike seems to be running well. However, when I went to adjust the pilot screws, tightening the screw (on the front carb) actually made the revs go up after a certain point instead of down like I would have expected. Is that normal? I figured less gas would bring the revs down.

[@HTMR]

Joshua, seems like your initial setting was to rich and you leaned it out resulting in an RPM increase. You want to tune both little by little until you reach max RPM and smoothest idle.

[@joshuasears4566]

MatthewMCRepair Thanks for the reply! I will fiddle with it more tonight.

[@HTMR]

Joshua Sears Let me know how you make out.

[@joshuasears4566]

Hey, I did it! I started with the rear carb this time and tightened it until the engine started to stumble, then turned it a half turn back and then I did the same on the front carb with no issues. Thanks again for your help and the great video.

[@HTMR]

Joshua Sears Good job!

[@stevendaniels8652]

Great video sir. You very good at explaining things....a natural teacher.

[@HTMR]

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

[@eastg6029]

I took off my carburator to clean it took it all apart put it back and my atv don't start any more and the problem is that I didn't measure the turns how do you measure the brass if it don't start you said it needs to be a hot temperature

[@HTMR]

If fuel screw, set it to 2.5 out. Air screw, 1.5 for starters. Just to get it running and fine tune from there.

[@AndrewMoizer]

Thanks for this. Been wrestling with an issue with my Honda GX620 engine for years. Finally found/realized there is a pilot air screw on the inlet side. Knowing that this is what it is, and screwing in richens up the mixture is the key. It ran better when I did this, but I wanted to be sure, as it seemed counter intuitive that in is richer. Now knowing that what I was doing makes sense, I can tweak it a bit more, plus feel confident that I might finally have this solved. Many thanks again for a clear, concise, and no BS video.

[@arimorell5976]

I really needed this, I have a Honda 250 1986 and it barely catches up with the RPM, I think the fuel is too lean cause it barely even uses fuel too. I am going to give this a try in the morning, thank you very much!

[@jeffwass8268]

how you meant to turn the screw when its underneath

[@HTMR]

I hate when they are underneath. In this case I use a screwdriver bit and hope I don't burn myself. Otherwise motion pro makes a nice 90° screwdriver that is crazy expensive.

[@jessewaldner8377]

just grab an old screw driver and heat it up and bend it into a 90 degree.

[@HTMR]

Good idea if you have room to swing it.

[@77jona]

yamaha raptor?

[@mikespain8655]

You can buy 90 degree bend screwdrivers (flat and Phillips) for cheap at Walmart or Harbor Freight.

[@Hahehhwgajshah72726..]

You need a longer screwdriver.lol.

[@tie-see9308]

Lmfaooo

[@alexschindler1629]

Very helpful! Thanks for the good content 👌

[@tomasz432tl]

It wos spark plug,bike runs perfect now and have even more power. Thanks for your time bro!Great videos!

[@nwlovell]

Very helpful thx! You get to the point, not much excess rambling or chitchat about off topic crap. Good explanation and demo of screw locations and effects on idle. I liked the screw comparison at the end.

[@prathapchandran5589]

nwlovell

[@Adikxx]

Absolutely fantastic video, so well explained

[@dakiemike4789]

Good on you mate ,well expanded, now i know exactly how to do it thank for that

[@yoshiakihisha8496]

Great Video, Thanks man, now i realized, i had backwards understanding of this screw, i thought that's control air, but i know now that control fuel, that's why my bike always have lean conditions

[@matthewreed4038]

Well explained and to the point. Thank you!

[@jonaspetzall]

Your video saved me soo much trouble and concern by narrowing down the problem with my bike, Thanks! (specially the part you explain if screw is by the motor its fuel - not air)

[@HTMR]

Thanks Jonas. Glad it helped.

[@robertmossmoss1758]

your videos are a life saver! thank you

[@anhtuanphan6159]

I'm learning about carbs. This is a great video.

[@EbaleyTheRogue]

This video was insanely helpful, Man. Thanks!

[@HTMR]

Dan Reams Your welcome, Dan!

[@Mokieyezplaytime]

great video dude, thanks for the real deal explanation. now that's what i'm talking about!

[@singerray1]

Good video man. BTW they make and sell a rubber plug for those air/fuel mixture screw tubes you can put in the hole after drilling it out. As you said they may not be necessary but I put them in my bike anyway to keep the trash out.

[@vauxmoto9096]

Great video man! Thanks! Subbed!

[@mikepool215]

You're a life saver. Thank you sir.

[@robd754]

good demo, that really simplified the process. thank

[@elbowroom7993]

So well explained that I understood everything. Thanks.

[@SpanishGold123]

Great video. Very easy to understand. Thanks for the info.

[@vmonster427]

Fantastic video, very nicely explained Thank you very much

[@jaikishorertmc]

Excellent stuff.. appreciate your efforts..

[@jetman1968]

You have the teaching bone… good job man.

[@charleswarburton8113]

This video helped fix my ATV. Thanks!

[@HTMR]

Glad it helped!

[@timtravasos2742]

Great info and explanation. Thank you.

[@kaseyod113]

So glad I watched this. Almost didn’t, but I learned a lot

[@bravofitnesss3178]

Subscribing and 100 more if I could!. Just bought a bike pretty much starting new on motorcycle stuff and riding ....you sr are a great help! Thank you so much

[@HTMR]

Awesome! Thanks for the sub!

[@mjdlos]

Great video by the way. Thank you so much!

[@yasharahlalove330]

Dude!.. Finally a great video.. Well done!..

[@HTMR]

Uploaded part 2 today: kzbin.info/www/bejne/en3PlaB4r9aFldU

[@flyingdutchmanSimon]

great video bro!!! keep up the good work

[@loganconner9325]

Awsome video! Really helpful thanks man!

[@HTMR]

Thanks, glad it helped.

[@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?

[@BrapStuff]

Great video! Clean ATV!

[@Jeremybaland]

Thanks for the video's. I am working on an XS750 and have to stock airbox on. I have a slight amount of fuel leaking from the airbox. Do you think the bike is likely running to rich? I dont think the floats are sticking because I just rebuilt the carbs.

[@leesuschrist]

This really helped me! Thanks!

[@jasoncaribou9530]

Now that was a great video bud 😊 , great stuff

[@HTMR]

I believe you are referring to the idle speed. If so, there should be a black plastic knob that you can turn to adjust to desired idle speed. The knob is attached to a flexible black tube that runs to the carb. The knob should be easy to access. Let me know if that helps.

[@HTMR]

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

[@thomassquires9752]

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??

[@Dumbokiller3]

Finally a video that tells me what I want

[@keving52002]

Thanks this video was very helpful to me in getting my 1996 Honda CBR F3 running again.

[@timothyconnecticut1910]

Now this man knows what he is talking about!!! Many you tubers have no clue !

[@1nowasol]

great! many thanks all the best Matthew

[@rodrheaume4612]

Great explanation. I've been adjusting screw to get bike to run well, but did not know what to shoot for (other than trying to avoid lag in throttle). Thanks.

[@HTMR]

Thanks! Glad you have it running well.

[@willc5562]

Excellent tutorial!!!

[@1nowasol]

HI MATTHEW --great video all clearly explained I have a problem with my Honda CA125 Rebel 1998, after firing from the exhaust pipe just behind the elbow of a small hole leaking fuel, it looks like this does not burn all the fuel to the end, what can be the reason and what should I do, I'm not a mechanic, and I'm looking for help thanks best regards

[@toddjacobs3988]

Yes very well explained, i knew that at one time, but forgot how that worked...

[@YL-er8zq]

Thanks man, That was helpful.

[@HandDugHistory]

Hi Matt, thanks for posting this video, for the first time I finally understand! I took notes and everything!! In your opinion, do you normally have to change jets if you take the airbox off and stick a filter on? I've got my project chinese 125 running now, (thanks to you) but it seems to be distinctly lacking power, nothing else has been altered (engine/carb-wise) except the airbbox removal..

[@leahmmiller6967]

yes. you need to up your jets to account for the increase in air

[@klipherrd]

So finding the "stumble" would it be the same for a carb that has an air screw versus your set up? (fuel screw?)

[@israelarredondo9957]

when in doubt, pull it out. excellent info. thanks man!

[@HTMR]

+Israel Arredondo Haha...your welcome.

[@reoii8020]

Really good and interesting video.Thank you.

[@wee7os]

great vid, thanks for clarifying this!

[@LukeSchiralli]

Best explanation I’ve seen thanks

[@colincherry7715]

A great video-very informative, thanks