Honda rebel 250 air fuel mixture screw 1x Fuel Mixture Screw. i live southwest of little rock arkansas, dont really know my elevation May 22, 2017 · 2009 Honda Rebel 250; 2009 Honda Shadow 750 Spirit "The bravest thing for me to do is admit when I am wrong" - unknown HRF Answer #1 You should take the MSF Rider Course HRF Answer #2 You need to clean your carburetor HRF Answer #3 Sorry we assumed if you didn't say otherwise Jun 2, 2014 · I think I asked this before but cant find it. Adjusting fuel air mix on Honda Precision CNC machined screw for Keihin FCR carburetors, It fits most common 4-stroke models: Honda CRF150R, Honda CRF250R, Honda CRF250X, Honda CRF450R, Honda CRF450X, kAWASAKI KLX450R KX250F KX450F, KTM 250 EXC SXF XC-F XCF-W, 400 EXC XCW, Polaris Outlaw 525 S, Suzuki RMZ250 RMZ450, Yamaha WR250F, WR250F, WR426F Jul 20, 2023 · [Compatible with For Keihin FCR Carburetors]: Universal Air/Fuel Mixture Screw Adjuster for Keihin FCR Carb Motorcycle Compatible with Suzuki RMZ,Kawasaki KXF KLX,Honda CRF,Polaris,Yamaha YZF WR, (Details Use Vehicle type to view the long description) [Package include]: You will get 1*Carb Mixture Screw with spring, 2* washer,2* O-ring. May 4, 2012 · My question is the air / fuel mixture screw has a washer + oring + spring. you brought wrong size or wrong item). Bike is an 87 honda rebel 250. 1 1/4 pipe IMO is way to small and it needs to be 1 1/2 or 1/2 plumbed to a 2in pipe but again depends on location. With the engine idling, turn the screws in or out to achieve the highest idle speed. g. The bubble effect breaks up the mixture so it sprays better when it exits through the transition ports (13) and past the pilot screw (PS) through the pilot port (12). This is the one that Buy your Air Fuel Screw Kit - Carburetor - GL1200 - VF1000 - VT750 - VT1100 from Randakk's Cycle Shakk. Fits For KTM. Mar 4, 2021 · Do i have to take my carbs off my 06 shadow aero 750 with dual carbs to adjust the air fuel screws? My 600 had a tj brutal customs knob on it and was single carb was pretty easy Here's a quick trick to know which way to turn those fickle air fuel screws just by looking at any carb body! #shorts Subscribe for the upcoming complete ser Nov 11, 2010 · Fuel/Air adjustment Hey guys, I need some help here, i need to figure out how to make a carburetor fuel/air adjustment for a 1986 Honda 250 trx, because that is the only way I think it will run. Gonna use 'em to build another bike! How to make a Signature | Honda Rebel 250 & 450 Forum (hondarebelforum. Get color photographs, color wiring diagrams, specifications and step-by-step procedures. Thanks for the love and everything on the part one s Apr 2, 2018 · Air idle mix screws are on the air filter side of a carb, Fuel idle mix screws are on the throttle/manifold/piston side of the carb. heating with soldering iron will weaken adhesive enabling tab to be removed from screw head. Shop for Fuel and Air Intake Systems, like Tusk Fuel Mixture Screw at Rocky Mountain ATV/MC. Fits all Keihin FCR & FCR-MX Carburetors, fits most common 4-stroke models. As you open it, you add a richer mixture of both fuel and air to the idle mixture. Tuning the Air-Fuel Mixture Locate the mixture screws, usually located near the base of the carburetor. With the engine off, turn the screw all the way in counting the number of turns it takes. k. View and Download Honda Rebel 250 2016 owner's manual online. from the picture my guess is yours is fuel not air. a. the AF screw won't back out on it's own due to the pressure spring and o-ring friction places on it. Jan 26, 2009 · Next, adjust your “air/mixture screws”. Jan 18, 2018 · The black knob (idle stop screw) just limits how far the throttle can fall closed when released. I have cleaned the carb, and cannot find the settings for these two screws. The screw adjusts how much air is allowed through the pilot jet. Jun 8, 2010 · The "pilot" screw is what I call the "idle air/fuel mixture" screw, because that's what it does. Rebel two fifty, and i've known found that when I screw the air fuel needle all the way in it doesn't stall the engine. Curious if I'm correct of the fuel mixture screw cause im gonna be May 7, 2020 · The air/fuel screw doesn't seem to do anything but all the parts are there. Sep 11, 2019 · The pilot jet (PJ) draws fuel from the main jet (MJ), and meters it into the slow jet, which has air holes to mix air from the slow air jet. Rebel 250 2016 motorcycle pdf manual download. More at https://www. Similarly there was gas on the drain screw as though that could have been leaking. Anybody know where I can find a new mixture screw, preferably aftermarket. The screw adjustment (explained in the video) is used to fine tune this adjustment at idle speed only. The idle circuit only works at idle and small throttle Jan 21, 2019 · 2001 400ex with aftermarket pipe and one 2" hole in air lid. the accelerator pump is a pain to get completely clean after 2 years of sitting. Aim for a balance between rich and lean mixtures for best results. The screw actually adds fuel and air, so it is not purely an air screw. Apr 17, 2017 · The idle mix screw on a rebel carb is a down-stream regulator, which adjusted the amount of fuel added to the idle mix. I set the screw to 1 1/2 turns out and put everything back together without the air filter. Nov 24, 2016 · The air fuel mixture screw should be about 1 1/2 to 2 1/2 turns out. -The engine must be warm for Sep 1, 2011 · well, I installed Jardines and had an off throttle backfire problem shimmed the needle and that seemed to almost completely eliminate it then i went to a pod filter and got much crisper responsiveness, but ended up with the backfire again NOW: . Nov 15, 2013 · 2009 CMX250; one black, one blue '89 VN750, 2006 ninja 250 Keepin' all the left over parts. (E. May 18, 2013 · when disassemblying my carb. com) More at https://www. Basically, I'm in my shop manual under 4-14. I replaced the air/fuels mixture screw today and not sure where to set it at. Oct 9, 2022 · The idle screw has a black knob and is on the right side, behind the muffler and a tube The screw is upside down ("right" and "left" may feel reversed as you look down), regardless, "right" means "clockwise from the face of the screw" as in "righty tighty". Last edited by robindean; 07-28-2015, 07:50 PM. thejunkmanadv. There is a cap on it which prevents it from turning very far. Air under atmospheric pressure is bled, into the carburetor fuel passages to improve fuel atomization, to stabilize fuel height in the jets, and to provide corrections in the air/fuel mixture ratio. adjust the air fuel mixture Oct 3, 2023 · A forum community dedicated to the Classic Honda Rebel 250 & 450. it's got an o-ring on the end. It usually takes forever to get started and it sounds like something is slapping/clanking around in there often as we release starter button. Think I'm going to try the 42 pilot and 170 main, right now it has stock pilot and 150 main. It controls the air/fuel mixture at and just above idle. Now I don't know how to get it back in at the right adjustment. The A/F mix screw, really the pilot screw, only fine tunes airflow at idle. Repairing the dual carburetors on my 1986 Honda Rebel CMX250. I don't care what make or model you have. Reference fit models as following. went to try a calculated adjustment on the air Aug 9, 2023 · In short, the carb really doesn't need adjustment other than the air/fuel and idle screws. Mar 30, 2011 · There is a tab that has to be removed if it hasn't been already that allows the A/F screw to be adjusted. Anyways I stupidly adjusted it too far rode and when I looked back at it it was gone. And The idle air flow (idle speed) is controlled by a conventional screw that opens the Primary Throttles. Jul 17, 2024 · Is there any way to screw the fuel/air mix in more without taking the entire carburetor off? I f*©%ed up and didn't screw it in far enough before I put carb back on. It can also keep the bike from running if too lean, and will turn exhaust pipes blue if left in this condition, as well as burn the valves. Fits For Honda. The idle mixture screw is responsible Jan 1, 1983 · Visually inspect your tires and use an air pressure gauge to measure the air pressure at least once a month or any time you think the tires look low. I watched several youtube tutorials and they all say the fuel -air mix screw should be set at 2 May 18, 2017 · My choke needs to stay on for a lot longer than my friend's bike (also a Honda Rebel). Come join the discussion about performance, modifications, troubleshooting, maintenance, reviews, and more! Oct 8, 2015 · That is the idle air screw #5 in the link below. Note: -The pilot screw is factory pre-set. Off idle, it does nothing. From lawn mowers to motorcycles this is the best way to dial in your carburetor for a fine tune adjustment for your Idle mixture screws. Does that matter? Nov 1, 2016 · Buy NICECNC Red Universal Air/Fuel Mixture Screw Adjuster Keihin FCR Carb Motorcycle Compatible with Honda Yamaha Kawasaki Suzuki CRF YZF WR KXF KLX RMZ,See Fitment: Carburetors - Amazon. In this video I rebuild the Honda Rebel 250 carb, and and give you some dos and don'ts on how to DIY it. I've had the bike for 1k miles and I haven't had any problems. Of you have never rebuilt a carb make sure when u take out the air fuel mixture screw there is a tiny washer and o-ring. . How do I reinstall and set the air fuel mixture correctly? Nov 17, 2024 · Hello, posting about my 2007 Rebel 250: I recently removed the carb and did a deep supersonic cleaning of all the parts and internals and reinstalled, prior owner stated it was like gummed up and I confirmed that. Jan 19, 2006 · The throttle valve of the left carb (facing engine) is adjusted using the throttle stop screw until the throttle valve edge aligns with the bypass hole. Adjusting the Mixture ScrewsClick on a thumbnail to enlarge. Where do I buy one? May 4, 2012 · The pilot jet (or slow jet, handles mostly the first 1/4 of throttle. It is right in front of the float bowl. It's backfiring on high rpm decel so I believe I'm running lean. Feb 6, 2018 · Idle FUEL Mixture Screw on Honda GL1000 A super sensitive shop quality tach will help a lot. Oct 10, 2017 · There is a pilot screw on the bottom adjacent to the bowl, and what I think is an air mixture screw on the side of the carb body. It started up almost immediately, idling up and down, before the water killed it. Loosen the idle screw until the spring has no tension. And when it comes to the Honda 250 Rebel, one component that stands out is its carburetor. We are your #1 source for Honda Vintage Motorcycle Parts. Jul 10, 2025 · What Does The Air Screw Do? The air screw is the "fine-tune" adjustment for the pilot jet (sometimes called the slow jet). Put on clear fuel tubing and a fuel filter. This cap has a little tab on it that hits the float bowl. Jan 9, 2011 · Hey, just brought a 250 Rebel back to life. Adjusting this screw changes how fast or slow an engine idles and how smoothly it runs. I have a 1987 250 rebel with 10,000 miles. So please take a moment to register and introduce yourself. Here is a comparison chart: Spark Plugs Jul 20, 2023 · [Compatible with For Keihin FCR Carburetors]: Universal Air/Fuel Mixture Screw Adjuster for Keihin FCR Carb Motorcycle Compatible with Suzuki RMZ,Kawasaki KXF KLX,Honda CRF,Polaris,Yamaha YZF WR, (Details Use Vehicle type to view the long description) [Package include]: You will get 1*Carb Mixture Screw with spring, 2* washer,2* O-ring. Jun 25, 2018 · The air/fuel mixture screw, which has a tab on the head, if a previous owner didn't remove or cut it off, is initially set at 2 3/4 turns out from lightly seated for second generation (1996-2016) Rebel 250's, and 2 1/4 for first generation (1985-87). It had been well taken care of. Mar 24, 2024 · Probably no where on a rebel 300/500 forum page. Feb 14, 2019 · That screw on the bottom of the float bowl is the drain screw. for cleaning on my 2006 Honda Rebel I did not count the turns on the air fuel needle. The kit came with fuel air mixture parts. Is there a way to replace that seat?Or am I gonna have to replace the carburetor? Jul 30, 2013 · You can also just get a new fuel mixture screw at Honda, Kawasaki, Polaris, Suzuki, Yamaha, KTM, Can-Am, & Sea-Doo Parts - CheapCycleParts. Follow along as I diagnose the problem and restore life to Nov 24, 2012 · The air/fuel mixture screw is located in a boss under the front of the carbScrew in all the way in GENTLY until it stops,then slowly back it out 2 1/4 FULL turns (not half turns),and then if it idles too roughly (assuming the carbs spotless inside,and jetted properly) turn the idle screw on the right side inwards until it will just barely If the engine RPM’s drop on the FIRST 1/4 turn from the starting point, turn the screw back to the starting position and wait 30 seconds until the engine responds, then go to #2 2) TO MAKE THE AIR/FUEL MIXTURE LEANER: Turn the Air/Fuel Mixture CLOCKWISE 1/4 turn and wait about 30 seconds to allow the engine to respond to the new setting. How critical is this part? Jul 28, 2015 · I've been trying to wrap my head around it all day but don't see anything under terms I'm used to, namely "fuel/air mixture screw" or "enrichment screw" hence my query. The starter sounds like shit. Part #16016-KEN-670 at ccp. If you look at it, you can see that the cam on the end of the throttle butterfly shaft stops against the end of this screw. just wanting to make sure its tuned right. Jun 13, 2014 · How-To video on adjusting the fuel screw on a 4 stroke dirt bike. 2. com) Aug 23, 2020 · The idle mixture screw, also known as the pilot screw, does have an effect at all throttle settings, but certainly more idle up to about 1/4 throttle where the main jet become the main source of fuel. Too lean of a mixture, less gas more air, results in too hot of a firing. To set it properly, the idle drop procedure is recommended by Honda. Fuel flowed in, but then so did some rusty water that I didn't realize was there. Also for: Cmx250. Something felt off with the engine when riding so I decided to investigate. Jul 22, 2009 · I was on mental cruise control when I pulled the screw with the spring under it (is that the jet?) inside the carburetor and I started counting turns to unscrew it instead of counting turns to screw it in. Thanks very much. Be sure to readjust the main curb idle adjustment screw to maintain 1000 rpms as necessary… before and after each idle mixture screw adjustment. If you end up at some extreme, like all the way in or 3 or 4 turns out, you have a problem somewhere in the carb - probably indicates The Pilot jet only controls the air/fuel mixture at idle and low, off idle, throttle openings. Aug 29, 2009 · The air mixture screw is located at the front/bottom/center of the carb. start with the air fuel mixture screw at 2. Number 18 in the above diagram is the idle adjustment screw, which has ho connection to fuel. Nov 26, 2015 · Alright,,,, when I set #3 screw to 2. com Twitter: / thejunkmanadv Facebook: / thejunkmansadventures How to adjust the air or fuel screw on a typical motorcycle or ATV #carburetor. Drained the water from the Jun 7, 2023 · Just got my first Honda rebel 250, it's my first bike, cleaned the curb, but I'm having issues with it, im thinking it's the air fuel mixture screw, but I'm here to ask for help just incase, so with the air filter off giving it throttle it goes, but the second I out it on and give it throttle it's it bogs out and shuts off. Oct 31, 2025 · Fuel Mixture Screw for Keihin FCR Carbs. But what exactly makes the Honda 250 Rebel carburetor unique? Jul 7, 2020 · We have a very friendly and knowledgeable group here. You can try adjusting the air fuel mix screw. The tachs on vintage bikes are notoriously inaccurate and not sensitive enough for this procedure. Here's how to set idle: How to tune air/fuel mixture? | Honda Rebel 250 & 450 Forum (hondarebelforum. My main question is which screw is the Feb 13, 2014 · Topic should read: Engine cranks but won't start I recently purchased a 85 rebel 250. I read that it’s on the left side/underneath, and is a flathead screw? Just got my first Honda rebel 250, it's my first bike, cleaned the curb, but I'm having issues with it, im thinking it's the air fuel mixture screw, but May 1, 2010 · I counted the turns on the air fuel mixture screw and it was set at 2 3/4. Don't know how much this matters either but my air/fuel screw doesn't have a rubber o-ring. — Adjust the idle speed, and pilot air mixture screw per the service manual. That screw should be screwed 2 and 1/4 turns out from lightly seated before the float bowl is installed. Too rich of a mixture, more gas to air ratio, will keep cylinder temperatures lower, but can foul spark plugs as well as lousy Jan 26, 2023 · to prevent tampering with AF mixture which was set at factory to comply with exhaust emission standards yet allow for slight adjustment. Aug 21, 2013 · The only adjustments on the carb are the mixture screw and idle screw. com - Cheap Cycle Parts That's what I did when I lost the rubber o'ring on my fuel mixture screw. com) Jul 11, 2017 · After cleaning a carb: Idle fuel/air mix screw set to factory 2. Feb 3, 2025 · I'm trying to tune my 2008. Putting my carb back together (2014 250) after cleaning. Oct 10, 2021 · Re: Carb air/fuel mixture screw adjustment by Rideslikenacho » Wed Aug 14, 2024 7:48 pm bonesv wrote: Tue Aug 13, 2024 6:15 am What scooter is this? The instructions for a 2-stroke honda scooter says to turn the A/F screw clockwise all the way until it bottoms out (not hard). Nov 30, 2017 · there is only one mixture adjustment screw, on the Keihin carburetor. Enjoy! Cleaning carb, need to know how to set air/fuel mixture screw and other questions Jump to Latest 16K views 10 replies 6 participants last post by rfuria78 Sep 25, 2012 D Jul 18, 2013 · Can someone explain the difference and in what situation you would play with the fuel mixture screw and when you would mess with the idle stop screw? Or do they work hand in hand? My bike used to die on me while riding and I went through cleaning the carbs and setting the mixture screw to 2 1/4 Fuel Mixture Screw comes with spring, washer and O-ring, this motorcycle part fits all Keihin FCR & FCR-MX Carburetors,fits most common 4-stroke models: Honda CRF150R/CRF150RB, CRF150R, CRF250R 2004-2009,Yamaha WR250F, YFZ450, YZ250F, YZ450F 2003-2009, Kawasaki KLX450R Dec 3, 2013 · Hey guys, Can someone let me know if turning the air/fuel mix screw clockwise will make leaner or richer? I'm confused between which end is outlet/inlet etc when other people describe it. Fine-tune the mixture for smooth throttle response and optimal performance. May 24, 2012 · When I rebuild the carb, how do I adjust the pilot screw? Turn it in all the way? Back it out a certain number of turns? Also, I just noticed that the washer between the spring and the o-ring is missing. The tab is a limiter and keeps the idle air crew from being adjusted out side of the factory perimeter. Now I am without an air mixture screw / spring / washer / o -ring. Thanks to all of you. Always check air pressure when your tires are cold. First, let’s talk about the two types of mixture screws commonly found on carburetors: the idle mixture screw and the main mixture screw. Aug 11, 2012 · Start by cleaning the air mixture circuit and resetting the air mix screws to the factory spec. Jan 23, 2013 · Hey guys - new here! I have a 1986 rebel bobber. The Pilot jet only controls the air/fuel mixture at idle and low, off idle, throttle openings. if the engine starts, slowly back the idle down until its slightly higher than normal. Turn screw out to enrich fuel/air mixture for low altitude (more fuel for the denser air environment) ("air" meaning oxygen). For the right carb to synchronize, there's a synchronization adjusting screw located above (between carbs), that adjusting screw is encased in a spring with the screw head on top. My research tells me to adjust the fuel/air mixture and that's where I keep hitting a roadblock. Was going to replace the carb bit a new Keihin ve35a is $250-300. — Add an inline filter rated for 10 micron, or quit complaining about crud getting in your carb. Adjust the fuel-to-air ratio (FTA) by locating the slotted idle mixture screw near the air-cleaner side of the carburetor. idle stop screw turned in till it STARTS to depress the end of the accelerator pump Enricher (choke) engaged until the engine is warmed up. It would have little (read none) effect on speeds over 1/4 throttle. To remedy some throttle lag, some popping. If you did set the mixture screw when you reassembled the carb I'd say your problem is still a dirty carb. Turn the screw slowly clockwise to lean the mixture or counterclockwise to enrich it. It appears that one cylinder (the right one) is Apr 24, 2024 · Hey everyone does anybody know where I can get an air/fuel mixture screw set for my Honda met 2007. I didn't see the washer and oring until I cleaned my soaking tank (bowl) after bike was running. The mixture screw should have been set to it's initial setting of 2. Turning it clockwise will make the mixture leaner, while turning it counterclockwise will make it richer. Here is a comparison chart: Spark Plugs Precision CNC machined screw for Keihin FCR carburetors, It fits most common 4-stroke models: Honda CRF150R, Honda CRF250R, Honda CRF250X, Honda CRF450R, Honda CRF450X, kAWASAKI KLX450R KX250F KX450F, KTM 250 EXC SXF XC-F XCF-W, 400 EXC XCW, Polaris Outlaw 525 S, Suzuki RMZ250 RMZ450, Yamaha WR250F, WR250F, WR426F Fuel Mixture Screw comes with spring, washer and O-ring, this motorcycle part fits all Keihin FCR & FCR-MX Carburetors,fits most common 4-stroke models: Honda CRF150R/CRF150RB, CRF150R, CRF250R 2004-2009,Yamaha WR250F, YFZ450, YZ250F, YZ450F 2003-2009, Kawasaki KLX450R Dec 3, 2013 · Hey guys, Can someone let me know if turning the air/fuel mix screw clockwise will make leaner or richer? I'm confused between which end is outlet/inlet etc when other people describe it. Jul 20, 2023 · [Compatible with For Keihin FCR Carburetors]: Universal Air/Fuel Mixture Screw Adjuster for Keihin FCR Carb Motorcycle Compatible with Suzuki RMZ,Kawasaki KXF KLX,Honda CRF,Polaris,Yamaha YZF WR, (Details Use Vehicle type to view the long description) [Package include]: You will get 1*Carb Mixture Screw with spring, 2* washer,2* O-ring. 5 turns, where does #2 screw need to be set at? Dec 14, 2010 · If that is the case you'll need to drill out the little aluminum cap that covers the idle air mixture screws so you can open them up 1/4 to 1/2 turn out. When I couldn't find where they belong, I panicked. Nov 24, 2015 · as long as its the last scenario with used oil and a little gas contamination, go ahead and change the oil with fresh oil and try again. To get the best fuel efficiency, as well as power, the carburetor on your Honda engine needs to be adjusted to provide the optimum performance. Mar 19, 2019 · I see this is a common issue here! Hope to get the small oring at NAPA- guess it kind of holds the screw in place and seals the passage, is the washer necessary too? Apr 12, 2010 · is the adjustment screw on the bottum of the carb for your idle or is it your air fuel mixture? also how can you be sure if its running lean or rich? just took apart my carb for the first time to clean it and ran my two vent lines up to the headlight. 75 turns out from lightly seated when you put the carb back together then fine tuned after it's running. while the engine is at idle, you want to increase the idle by about 100-200 rpms (which isn't much). Aug 30, 2011 · Tutorial for setting air/fuel mix Jump to Latest 20K views 56 replies 6 participants last post by 87Rebel450 Sep 3, 2011 8 Dec 26, 2014 · Idle jets let the gasoline into the carb for mixture. com FREE DELIVERY possible on eligible purchases Mar 21, 2018 · Turn screw in to lean the fuel/air mixture for high altitude (less fuel for a thin air environment). Adjustment is not necessary unless the carburetor is overhauled or new pilot screws are installed. (the other type on some other engines is an upstream, controlling the amount of air in the idle mix. it sounds like that carb accelerator pump isn't doing the job. 1st Gen Honda Magna and Sabre (1982-1986) General and technical discussion of the 1st gen V30, V42, V45 & V65 Honda Magna and Sabre. a. I have searched the forum Feb 15, 2016 · Well I tried to sand down the knob on my air fuel mixture screw on my 1995 cb250 nighthawk but I ended up scoring the side of the mixture screw. If it has been rebuilt by you or another, the screw with the tab has been replaced by a straight end with blade type slot and non-tabbed one usually. Been reading the forums on jetting. See full list on wikihow. Apr 6, 2012 · The choke enriches the air fuel mixture with more fuel, on older carbs the choke is a butterfly that when closed restricts or "chokes" the air causing a rich mixture for cold starts. Dec 3, 2019 · After reading some forums, I found out my bike is probably running rich, so I should adjust my air/fuel mix? I’ve searched for days and can’t find out where the darn air/fuel screw is. We have cleaned the carb multiple times and replaced certain carb parts,gonna tyr to list off as many symptoms as I can to figure out the issue. at this point it should start and run without needing to touch the throttle. Due to weather conditions and use, the carburetor adjustments can change, requiring them to be readjusted. I going to guess if you remove the lid off of the air box it's going to run good. Call it idle mixture adjustment, pilot screw, air screw, it still is the only adjustable part that is external. Particularly the accelerator pump passageways Nov 30, 2012 · The initial setting for the air/fuel adjustment screw is 2 3/4 turns out from lightly seated. Oct 6, 2005 · The pilot screw, also called the air/fuel screw, is number 22 above. This is important for jetting to get the proper air-fuel mixture. Cleaned the tank with vinegar and bolts. This is your baseline, if you are not happy with the adjustments. I have a 2006 as well but I haven't had it fall out on me yet. Jun 7, 2020 · Hello, I am new to the forum and just got my first motorcycle. 5 turns out, and adjust the idle in a few turns. When it comes to adjusting the air/fuel mixture screws on a carburetor, it’s important to understand that the direction in which you turn the screw will determine the effect it has on the airflow and fuel mixture. Apr 16, 2012 · what does everybody have their fuel mixture screw at? how many turns out? i need to adjust mine and need to know where to set the screw. Sep 22, 2025 · CRF450R 2002-2008. when going to restart, bike turned over and ran for about 2 seconds before Mar 2, 2022 · First thing I throw away when rebuilding carbs. It takes small hands or a special screw driver to adjust it. Is factory 2 1/2 turns out?? Passed 3 1/2 too much? Then if I get it Service your Honda Rebel 250 with a Cyclepedia service manual. Jul 30, 2023 · I just bought 2008 250 and decided to clean the carb myself. It should be turned out 2 3/4 turns from fully seated when reassembling the carb. Even many experienced mechanics don't want to do it. This is what I've found online. Conventional Idle Mixture Screws that provide a leaner A/F when turned clockwise and richer A/F when turned counter clockwise. Fits For Kawasaki. You may be getting some of these problems from not cleaning that circuit. I am not sure where the rebel 250 page is but someone smarter than me might chime in and point you in the right direction. Jul 29, 2025 · In your case The tube connecting carb?? Intake manifold rubber tube of first generation cracks or holes most certainly would effect the running as a vacuum leak will lean out fuel mixture. My question is the mixture screw has a an aluminum tab that allows the screw to go lean or rich just a little over half a turn. I was recently messing with the air mixture screw because the previous owner had chopped the pipes without adjusting the screw. Pull the plugs ans see what they look like. We have the best prices on dirt bike, atv and motorcycle parts, apparel and accessories and offer excellent customer service. Also where can I find a float needle, mine has a groove in it. Pilot Air/Fuel Screw Adjustment Explained - Single Carb - Part 1 How-To Motorcycle Repair 140K subscribers Subscribe Learn more My bike seems running too rich/lean, how do I adjust the ratio to get the mixture well and run better? How does the pilot/air-fuel mixture screw work? Dec 21, 2012 · The pilot screw sets the air/fuel mixture at idle. ) An air fuel mixture screw is a special screw on an engine’s carburetor that controls how much air mixes with the fuel. Jun 16, 2024 · Going to try to adjust the air/fuel mixture screws on the two carbs of a 02 Ace 750. This crucial part of the bike’s engine is responsible for regulating the fuel and air mixture, ensuring optimal performance on the road. I can only assume your Rebel is 85-87 as newer years had solid aluminum flange mount to connect carb to intake manifold. Usually, 3/4 turn out from full in will be a good place to start. com. Apr 4, 2011 · So I'm thinking floats are bad and are letting to much gas in and that's why the gas is dripping out the bottom nipple which now has a hose that drains down below the bike. I’m wanting to say that’s the air fuel mixture screw, definitely going to want to find out why it’s not there. Dec 30, 2023 · Long-Handled Air-Fuel Mix Screw - Honda Shadow This Long Handled Air Fuel Mixture Screw for the Honda Shadows makes adjustment to your Air/Fuel mixture an absolutely easy and simple process. eBay has some dual carb setups for $90 though. Here's a diagram of the throttle ranges and how they Jul 28, 2014 · 1. -- Precision CNC machined screw for Keihin FCR carburetors. Thanks! Aug 6, 2012 · If that doesn't fix it, you'll probably need to remove and thoroughly clean the carb. Aug 25, 2021 · Shop for Tools, like Dynojet "D" Shaped Pilot Fuel Screw Tool at Rocky Mountain ATV/MC. Limits ability to adjust Air Fuel mixture. Due to a busy work life, what would be a good starting point for the air/fuel mixing screw to be at roughly? If it helps I live in CT near Hartford, the bike has 10k miles, and new plugs. When purchased, the engine would start and run, but if you gave it too much throttle it died. I’ve been working on my scooter finally got everything put together and started running it but I How to remove the emission cap-welch plug covering the air/fuel mixture screw with ease so you can fully service the carburetor. To adjust the fuel/air mixture on a 1986 Honda Rebel 450, locate the carburetor’s air screw near the intake manifold. Nov 21, 2023 · So glad this is posted. What should the air/fuel mixing screw be set at for stock? 2. (I don't have my tab either). did you change it when you did the carb rebuild? even if you didn't you can screw it down tight enough so it doesn't drain. Remember this is a Honda Shop Manual, certified mechanics Must meet product liability requirements or shop could be liable. Adjust back and forth for maximum rpm, on each carb. Venturi). Carburetor tuning is part science, part wizardry, and part luck. That Aug 28, 2007 · Pilot Screw Adjustment for the Recon 250 ('97 and up) This may also be suitable information for the same year 250SX quad. Fuel Mixture Screw for Keihin FCR Carbs. Sep 1, 2011 · well, I installed Jardines and had an off throttle backfire problem shimmed the needle and that seemed to almost completely eliminate it then i went to a pod filter and got much crisper responsiveness, but ended up with the backfire again NOW: . Operating the Honda engine with the wrong adjustment settings can Apr 16, 2009 · This circuit consists of pilot air jet (s), the pilot fuel jet (s), a pilot screw (either fuel or air screw), and pilot ports inside the carburetor throat (a. Pulled the carb, soaked it, blew out the passages, and put it back together. com Jul 5, 2014 · SETTING THE AIR/FUEL MIXTURE To set the air/fuel mixture screw you need to have a warm engine. Any suggestions? If your Honda Rebel 250 carburetor is running rich, you can try adjusting the fuel/air mixture screw. (make sure you take note of the OEM setting for number of turns out from full in) Apr 30, 2025 · Master your motorcycle's idle mixture screw with this pro guide—tune for peak performance using the throttle snap test. May 19, 2016 · I'm not sure whether someone might have overtightened the idle mix screw - when I got home there was a drip of fuel on the end of it, but this might have just run down the outside of the carb. 75 turns out from seated.