Running lean on deceleration. You are running way to lean at WOT, when your pedal is all the way to the floor the leanest you should be running it 12. We were riding at about 3500-4000ft. The popping sound is from unburnt gas in the exhaust that is ignited by the heat. itsatdm , Dec 26, 2011. set properly. 2017. The pilot that is in there is a 42. If we have initial velocity, final velocity, and distance traveled, then we can compute deceleration as: a = v2–u2 2s May 21, 2006 · The a/f screw is about 1. Aug 9, 2022 · If you notice that you’re running rich, you’ll want to check the following things: Mass airflow sensor – check if that is dirty or defective. Basically when the engine warmed up it was running way too rich causing fuel to build up in the exhaust and detonate on deceleration. Aug 19, 2023 · 08-20-2023, 05:21 PM. As for the exhaust noise. The reason for the popping is that the lean flame burns longer thus going out the exhaust (I could be wrong on this) Mar 17, 2011 · 788 posts · Joined 2007. Do you know if your new exhaust is commonly used as a replacement on your scooter? Apr 29, 2006 · As you already know, when a bike runs lean it also runs hot, burns plug electrodes and can pre-ignite (bad). 5 as i have it set in the programming. 5, 2, 2. Apr 14, 2019 · Hi paul just wanting a bit of advice on a problem a car is having in my workshop. I've read that a black plug means you are running rich and the popping on decel means you are lean. Originally posted by Irish916. 3L with 862 heads, Jegs 283°/286° cam, 92mm throttle body, Dorman intake, 78/75mm turbo Jul 13, 2004 · J. Hard starting when hot. Model:Conquest. 5 you can be causing some pretty bad damage to your motor, however, the numbers you posted up sound like your Jun 11, 2009 · In fact, the valves have probably tightened because the K&N was making the engine run leaner and hotter. When in "closed loop," the ECU can detect a lean, or Jan 20, 2006 · Why does a lean running engine have a tendency to excessively pop? The exhaust gas temperature of a lean engine is substantially higher than one that is running on the rich side ( an EGT probe will show this). Woods rider. This is because, in order to decrease the body’s momentum, the torso must assume a more erect posture compared to the lower body and greater posterior lean during deceleration. Posted December 9, 2005. I'm wondering if this could be due Feb 4, 2022 · Yes, lean will give you back fire. Dec 1, 2020 · 2019-2020 hunting season it did it a few times, this year it started doing it a lot and would quit running. Johnny KLR , Feb 24, 2008. Noticed more when on the kickstand or leaving fuel on while in the bed of the truck. I have found 2 different answers . lightly turn the outer plug inward until it just baaaaaarely brushes the copper platewhile idleing. I would have to wait a 5-10 minutes and it would run good for a while then backfire and quit. The engine is a new BPE SBC 427 w/2004r trans. With the cold weather up here in Sudbury, my Grizz was starting to backfire. the motor is a 1999, a 1999 evinrude ocean pro 90 hp running good would go for at least $3500 around here. jakalwarrior. When in highway speed, if I release the accelerator also the engine goes way too lean (also +17) and you can hear some engine sputtering on the exhaust Again, the lean "issue" is normal. Holley Sniper EFI on Amazon: Mar 19, 2008 · Found this also: "In general, backfiring on deceleration (as opposed to acceleration) is generally caused by a lean condition in the pilot circuit. I've been tuning on my car for a while now, but I'm currently fighting a lean deceleration issue. Can My Motorcycle Pop In A Safe Way? Yes, some motorcycles are designed to pop on deceleration. 3732 posts · Joined 2002. A lean condition can be caused by bad O2 sensors, map sensor, intake gasket leak, head gasket leak, vacuum leak, etc. Engine cooling temperature sensor – make sure that’s not defective. Feb 16, 2024 · Once a lack of flame is detected, it slows down on fuel injection, again runs lean, then overcompensates, and must repeat this cycle over and over again to keep running. The 3 cone L-Drill is a commonly used test for acceleration, deceleration, and change in direction for athletes. 7,876. Apr 3, 2011 · SHINKS07SS. The new mufflerr looks virtually identical to the old oneoem. When it is colder, the bike runs lean. If you really MUST ride it then either get it back closer to stock for this ride (or) - and these are just 'stop gap' measures. If the new exhaust is less restrictive than the one you replaced it can cause backfires, specifically during deceleration. A lean air or fuel mixture from the carburetor of a Harley Davidson results from drastic changes in the pressure. It is the primary source of all of that oxygen that is making the mixture in your headers lean. You know that when the exhaust valve closes, the flow out stops and air rushes in. Also, running lean tends to not foul plugs as much as burn and melt the living hell out of the electrode. , a receiver rapidly decelerating to create space from a defender to receive a pass) and to change direction. I have the spark timing right on the money, the valves are. ISBN: 9781098108779. My wideband is showing full lean (18+) under deceleration/engine braking with my new MAFT setup. With a closed throttle, there is no high pressure. Low compression that leads to an inconsistent burning rate for the fuel. Feb 4, 2022 · Yes, lean will give you back fire. The velocity decline is typically accompanied by a reduction in step rate . Mar 21, 2015 · Before the muffler change it wasn't making any noise. Also, viragos have emission controls on it that create popping on deceleration. All that aside, pulling the plug long after the engine was shut down is a pretty poor indicator of air/fuel mixture. -. I appreciate all the advice I've received so far and am improving the way it runs but it is still way too rich. Deceleration in court and field sports is important when executing certain skills (e. One major thing that causes popping is running very lean on decel before DFCO kicks in. 5, 3 etc still black plug. Counterclockwise. Loose bolts or a blown gasket there can cause the symptoms you describe. Posted April 25, 2007. I'm trying to get my FatBoy's tune back to where it was before I went and screwed it up. range. Jun 11, 2019 · The problem occurs when an excessive amount of oxygen makes its way from the intake port directly into the exhaust at idle and low engine speeds because of overlap. I have stock jetting no airbox mod and the stock pipe. O’Reilly members get unlimited access to books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers. Apr 9, 2009 · Mine backfired on deceleration and it was an exhaust leak. Backfiring could also result from poor timing. Jan 6, 2019 · Posted September 3, 2018. Oct 2, 2019 · had a chance to get the mustang out for a little ride and having issue. g. Apr 15, 2021 · Exhaust popping. Publisher (s): O'Reilly Media, Inc. Deceleration AFR. To keep that optimal force output, make sure to keep your knees high and don’t skimp on the arm action during the final stretch – keep your elbows bent at a 90-degree angle! Aug 29, 2022 · That's normal with an aftermarket pipe. Jun 15, 2019 · I'm still confounded by a lean condition on deceleration. If the popping is indeed caused by unburned fuel igniting in the exhaust system, then presumably the only ways to eliminate it would be to (1) make the engine run more efficiently so it burns up all of the fuel in the combustion chamber and/or (2) cool the exhaust Aug 11, 2021 · I am finding that the carb leans out to almost 16 on acceleration and richens to 9-10 on deceleration. Deceleration = Final Velocity–Initial Velocity Time taken. 9 magnum efi swap for about 6mo and i recently started getting backfires on deceleration. Dec 27, 2005 · tpanfil. I've made adjustments to the ve table, sometimes significant, without any real improvement. You are bringing the ground up to them as they will be driving out and running in the 45 degree angle to the ground. #10 · Apr 5, 2011. At this point the plate is "sucked" in. The backfire will start to go away. The bike is a 2000 FatBoy, Zipper's Dec 9, 2005 · Throttlejockey. Jul 9, 2002 · Does running lean damage anything, or is it just a performance issue? My '97 XR 280 runs goodmild backfire upon deceleration from high RPMs. Apr 1, 2024 · Schematic diagram of implementing the spindle deceleration energy-saving strategy (n 1 = n 2): (a) The power curve and energy demand of the machine tool running in the original preparation state; (b) The power curve and energy demand of the machine tool spindle system when implementing the deceleration energy-saving strategy; (c) Power curve Transition from deceleration to a backpedal, running backward to return to the first cone. 2. Is there an air injection system on the Vulcan that puts fresh air into the exhaust port upon deceleration to burn unburned gas fumes (an EPA thing)? If so, remove the pump and cap the ports. « Reply #16 on: February 20, 2016, 01:11:39 PM ». I'm not sure if it's a false lean or even if I need to be concerned about it. 2 AFR (for gasoline) where we find the fuel efficiency is fantastic. Read it now on the O’Reilly learning platform with a 10-day free trial. Jan 18, 2002 · So after adjsting the first 1/6th turn on the center screw. Sep 15, 2016 · Posted September 19, 2016. Apr 1, 2024 · Schematic diagram of implementing the spindle deceleration energy-saving strategy (n 1 < n 2): (a) The power curve and energy demand of the machine tool running in the original preparation state; (b) The power curve and energy demand of the machine tool spindle system when implementing the deceleration energy-saving strategy; (c) Power curve Mar 25, 2009 · I was just trying to get a feel for the size of the possible repair a knock could throw my way. It cranks up and idles fine. 8, that is the max, most people only push it to 12. Feb 20, 2016 · Re: Popping on Deceleration. 1 is stock voltage and the other is with the vortex it doesn’t matter. Checked with some mechanics, some said clutch slippage, some said throttle position sensor. Sorry for the stupid question but I can never remember. The knocking during deceleration is not detonation. :greenrzr: RZR#2 Aug 19, 2023 · 08-20-2023, 05:21 PM. It still stumbles off idle a little, sometimes going to full “LEAN” message on the AFR gauge and the same for a 3rd gear full throttle pull. If you are more than 3 turns out then you need a richer pilot. While riding today I noticed my bike popping intermittently today on deceleration. It was also running lean according to the plug. On decel, any vacuum advance is going to be pegged out, so the exact specs of the unit are irrelevant to your popping issue as long as you have vacuum advance in the 16-degree range. Noticed a few things pretty quickly: 1) Gas Leak. And running lean another. Not loud or anything, just a burble kind of noise but with a very slight pop. During deceleration the car goes super lean 9. Then you know for sure where & when DFCO kicked in. If it dosent girgle go another clip or until it does, then back down. If he didn't richen up the jetting, it's too lean. JD Jetting tuner for the FI 2022 KLR650. Depending on the sport, these changes in direction can occur from different approaches. Feb 18, 2004 · ZIGZAG. I also read a few posts about carb slides hanging, choke Nov 21, 2019 · For more information regarding the sprint running technique, we refer to previously published biomechanical analyses (e. 2 then at idle settled at 14. turn the outer plug outward 1/2 of one turn. Hopefully the log will show this. I changed the accelerator pump to the . I'm getting some popping in the exhaust when I let off the throttle and I can't remember if it means I'm rich or lean. By design the extra oxygen it provides is there to burn off any unburnt fuel from the combustion process. Put it back to stock, or re-jet. it will pop like a gun just went off and shoot like a 1 foot blue flame out the exhaust. JD Jetting sells a fuel tuner for 2022 KLR if you want to add more power. Once i give it gas and the TPS is anything above zero the AFR's come back up to 14. Stock engine and carb. After 2 visits to the dealer, it's finally fixed. All of those symptoms mean your motorcycle or ATV is pushing unignited fuel through the exhaust system and then out the pipe. Black soot around the end of the tailpipe. Mar 6, 2021 · Fairly large camshaft. So my question is would a Exhaust leak near the header make it backfire. May 3, 2015 · FreelancerMG. You could had your problem solved if you had contacted twisted development. If starting velocity, final velocity and time taken are given, then Deceleration Formula is given by, a = v−u t. Jul 6, 2006 · All of the above setting over lap each other but your bike is running lean, this from the fact that you took the filter out and the bike popped more. This imbalance can be caused by various factors: Vacuum leaks, which disturb the air-fuel balance. Once timing is set up right, any popping on decel is related to a lean condition, regardless of Jun 14, 2019 · Finally got the mustang inspected and on the road. The combo is as follows: '03 5. Ragged idle …due to “loading up” of unburnt fuel. Gender:Male. 04-14-2021, 03:47 PM. i have a full yosh rs3 with a power commander and map from their website and it still afterfires on decel in high rpms. #13. Although the initial body lean is rearward, as athletes slow, they are often required to undertake a sport-based task, which requires them to assume a traditional athletic position and the associated forward lean. I read 20-50 oil works best, so I used it. The fix: Remove the tank and siphon the bad gas out by using a garden hose. #1 ·Apr 13, 2010. Sep 3, 2012 · I have posted before about Having alot of decel popping and what I thought to be the bike running lean. When decelerating, or braking, the forward lean seen during forward acceleration is not evident. Mar 18, 2009 · Backfiring On Deceleration. I put a wideband on the exhaust and it shows the engine is running at about 12. Then Apr 14, 2019 · Here’s a chart that can give you some clues of Rich vs. Lean: Rich Symptoms: Poor power output. 1. Released March 2022. Common to most situations in which deceleration occurs is the need to initiate a propulsive force soon after the deceleration. My guess is that it is just running lean. Self learning status and CL status goes from green to blue as soon as the TPS is at zero. 8 AFR at idle. Dec 7, 2018 · In an R32 GTR, because of the transmission gearing, the rear differential gearing, we typically see these engines cruising at 2500-4000rpm - or about 90km/h to 130km/h. Sounds to me the tps needs to be set at the stock voltage and the Vortex ecu adjusts the tps for optimum performance . heck I have been looking at most any 90-115 hp from the late 80's running is at least $2500 and up!! this guy is only asking $700 and it comes Jan 13, 2023 · Its lean, its cant be lean and rich at same time. If it gurgles and misses go back. If really lean it will not ignite fuel (flamout) in the cylinders and fuel builds up in the exhaust, when the throttle is tipped in, the fuel in the exhaust ignites and hence the exhaust pop. It decels at 12. Running rich/lean and what affects it has on EGT's with or without catalytic converters. , [20, 24, 33, 34, 38–51]). Feb 8, 2015 · If so, maybe it is running lean. Current jet is a 160 main and a 25 pilot. First time they richened up the mixture screw (or whatever it's called) and this time they actually rejetted the bike. i even had a friend video tape Jun 6, 2010 · 7. When the spark plug tries to ignite the air and fuel mixture, the combustion can be Jan 15, 2006 · as the one guys said before, backfire is a pop through the intake. It IS running lean on deceleration. Though my tune isn't perfect yet, it's really acceptable in most driving conditions, except when I lift off the throttle cruising 2000-3000 rpms or so. Nov 16, 2013 · That's weird didn't get a notification for all the replies anyway thanks for your responses. 3 Cone L-Drill. Mar 22, 2018 · A fuel injection system, via a slew of sensors, including a wideband sensor, has the means to intelligently react to changes in combustion. Starts too easily when cold – requiring little or no choke. Here's the part I don't understand Mar 14, 2024 · Backfiring is usually the result of a lean air-fuel mixture where there’s too much air and not enough fuel. So its bringing up a code for post cat a/f sensor reading lean, the thing we are struggling with is have observed fuel trims and we dont seem to be getting anything out of the ordinary and the code is logged when on deceleration and only at about 800 rpm. Running lean would mean your short a bit on fuel in the mixture. Nov 26, 2020 · 11-26-2020, 09:21 AM. It seems as if it's running lean. A lean condition in your engine is terrible for the engine internals. The backfiring was caused by a rich condition. Runs worse as it warms up. Responds readily to the throttle when cold. EVERY 400ex should be be running a 42 pilot at min! even if stock. Hey folks! Running the PF4 4150 setup on my 1967 Impala. #1 · May 12, 2010. Mains depend on air filters and exhaustsblow in a 180 and start from there, if it feels like crap riding than is flooding it. 15 hours ago, phatfos1 said: I had this happen. when doing this at highway speeds running in 5th gear, like to pass someone, it actually bucks and refuses to accelerate. I'm wondering if this could be due Nov 9, 2021 · LEAN! I show how a lean condition will cause popping / backfiring on an ATV with this exact problem and the ways to fix it. Jan 13, 2018 · Hill running. Im converting to a heated o2 setup later today and crossing my fingers this fixes the problem. Jan 10, 2016 · 2. Maby a quarter of a turn. Just remove the PAIR system and install block-off plates. Jul 1, 2012 · If it is a relatively short period of time, a little bit of carb cleaner will usually do the trick, but sometimes the carbs need to be dissassembled and cleaned. #3 · Jul 13, 2004. I have heard a lot of people say that decel popping is a sign of lean running. RZR #1=Green Gen 1, ITP mudlites, 2" lift, FMF pipe, UMP air filter, Polaris Roof, rock sliders, front and rear bumpers, wink mirror, 3000 lb Warn winch, 10 million scratches, 9th place 2010 GNCC UTV Open/Limited class. After diagnosing a few things, it turned out that it had the original fuel filter on it. Aug 21, 2007 · If tightening the header bolts doesn't fix the pop, it running too lean which will raise the running temp. A radiator shop is a good place to take a leak. Sep 24, 2007 · Of course you know that a lean fuel trim is caused by the ECU not adding the proper amount of fuel to match the air intake or extra air entering the system after the air intake has already been metered and proper fuel accounted for. Then as a baseline adjustment. 7. Jun 7, 2020 · Posted June 7, 2020. So ive been running my 2000 5. Ive been reading on a causes of this. Jul 29, 2015 · Quadrajet Advice -- Running Too Rich. On decel with not enough air getting into the engine will cause fuel to burn in exhaust when it hits the air. 3k. This action of the torso moves the center of mass behind to the base May 12, 2010 · 493 posts · Joined 2007. Apr 12, 2010 · 6900 posts · Joined 2008. With all this jetting talk, I am wondering if I need to check my jetting. The other comments about it running lean are probably correct but I think there’s another possibility to be aware of. This thread is to help me and others grasp the hole idea of how an engine and it's components (Forced induction or Naturally aspirated) react to running rich or lean on acceleration or deceleration cyles. Never had this before so Im thinking the jetting is now off. I use to swing spanners for a living. Backfiring on deceleration due to a lean condition is usually caused by fitting a free flowing exhaust or riding at a lower altitude. As an experiment, try just a little throttle on a decel while still in gear and see if it clears up. Exhaust and/or spark plug smells like fuel. Location:Pine Bush, NY. only way to get it done. by Ash Maurya. 1281 posts · Joined 2008. I’m noticing annoying pops on deceleration at low RPM. If I touch the throttle when it's at 35 AFR, it bounces back quickly but it's super lean prior to that. 043 nozzle and I’m running the linkage in the bottom hole. This is usually done for cosmetic reasons, and it is not harmful to the motorcycle. Taking out air restricion makes for a leaner running engine. Don’t worry too much about how steep the hill is but aim for a 15% Apr 1, 2023 · I have a 2016 KX250f, I just replaced the piston and rings, the timing chain, and shimed the valves, the bike was running perfect before the engine was just a little noisy, now the noise is gone but it's very hard to start pops a little when starting and bogs at low RPM and pops on deceleration, The deceleration phase is no different to the drive phase, except with the new challenge of maintaining your anaerobic endurance. #2. Interests:Toys & Candy. A motorcycle that backfires when you let off the throttle is running too lean. Drive it. Jul 18, 2021 · I wanted to give an update on this post in case anyone else runs into the same issue. ation while running (2,3,12). turn out the fuel screw to compensate for a lean pilot. Dec 3, 2021 · Dec 3, 2021. What AFR should I be running on deceleration. K&N filter with no lid. What happens is that the mixture leans out enough to where is fails to ignite consistently. Exhaust leaks seem to be one reason. Running Lean, 3rd Edition. Sometimes you have to give it a bit of throttle to get it to crank. Dart 427 with Pro Flo 4, engine seems to be running great but I am getting popping out exhaust on deceleration (downshifting). This also caused the stalling. 5 or so and then at around 1k it pops over to lean about 15. Tuning noob. I just brought it into the shop and their first guess was the intank fuel filter was causing the problem. Apr 24, 2007 · sandfly. The PO put in a K and N filter and after market exhaust which provides better air flow through the engine. Hey guys. Was running lean prior to the muffler change. This, in turn allows some un-burnt fuel to get into the exhaust pipes. Pro Circuit header and a Lexx silencer with race tip. 0-10 when the TPS is at zero. But if I clutch in at any point above 3k rpm, it'll go down easily. Sprint-specific endurance refers to the deceleration phase of the sprint. This is due to the drivetrain driving the RPM's up with the throttle closed, causing a lean mix. That is why you need to choke a bike (richen the mixture) to start it, especially when it is cold. Spark plug gives that sign, looks white not toasted brown/tan colored as it should. Mine runs like a top, but still has this. Perhaps it’s sending a false cold signal that causes Additionally, whenever I clutch in below this 3k rpm point, the rpm hangs for a second or two before returning to normal idle speed. Back down 10, go up 5 back down 2. As a result, your air/fuel mixture will escape the chambers while still being burnt. Once we've identified the engine's cruising speed, we then adjust these cells to ~ 15. But I get a little popping out the exhaust. I put a new silencer on today and have noticed when revving the engine, it sometimes shoots a flame out the exhaust. Make sure you log the DFCO Status Bits as well. I'm running the 3" GM MAF and MAFT on 650/950 injectors with a 12a turbo at around 13psi and an open downpipe. Therefore, the high EGT serves to heat the pipe more and the gases themselves become a much better source of re-ignition. Iv'e turned the screw in 2 3/4 turns to make it leaner, the loud pop on deceleration seems to have gone away, and the bike feels a little bit more responsive, but now I get random hesitation, seems the most noticeable when I'm cornering or opening the throttle downhill. You wouldn't be smelling it out of the exhaust as there wouldn't be any fuel left to be un-burnt to make it past the catalytic converter. After everything was installed the decel popping started. an afterfire is a pop from the exhaust. For example, a ball carrier in rugby may decelerate to Oct 4, 2007 · 76GMC1500 said: Yes, detonation occurs only during periods of high pressure/high temperature in the cylinder. Aug 12, 2023 · In most cases, the reasons behind motorcycle backfire deceleration are: Revved engine, which drains the fuel of its combustion chamber. #5 · Mar 18, 2011 (Edited) Its your o2's, convert them to heated o2 sensor. Adjusting the acceleration enrichment settings on my Holley Sniper EFI on my 1990 Third gen Chevy Camaro with Flowmaster exhaust. I double checked the bolt that blocked off the air injection for that smog thing and found that it had come a little loose letting air in. I figured out I was not releasing the throttle fully when shifting. I would think this would be opposite if the dashpots were slow to rise and sink. Works like a champ, no hesitation and no backfire even Other signs of a rich-running engine include: Black smoke coming from the exhaust. Too little fuel in the cylinder and an excess amount of air can be the culprit to your backfiring problem. To make it up, you will really have to drive the knees up high and you’ll be forced to run on the balls of your feet. See the pic. Turn the fuel screw out a bit. However if it's stock exhaust and the tune is close to standard, I would be looking for an exhaust leak in the header pipe. lower the clip on the needle to richen up the Dec 9, 2006 · Popping on deceleration can be a sign of lean runnning, but if it seems fine otherwise, I'd double check to make sure your exhaust header is sealed correctly to the head. I have 100 miles on the car, I have the "mild" cam setting loaded and the only changes I have made to my setup are the base timing and getting the IAC % down when engine is warmed up. I tried 1, 1. #14. #1. However, in many sports, the act of rapidly slowing the body (deceleration) is posterior lean during deceleration, moving the COM posterior to the base Jan 20, 2007 · 809 posts · Joined 2006. --Leaking like a waterfall out of the float hose. Oct 17, 2018 · It happened to mine. Posted December 27, 2005. Feb 2, 2020 · Do what you want. a crack in the manifoldmy 2 cents. Getting too much air and not enough fuel in your cylinder is called running lean. It is denoted by –a, where a is acceleration. O2 or air fuel sensors – make sure those aren’t lazy or defective. This repeated lean burning and overcompensation will cause the engine to surge and stall. Incorrectly adjusted carburetor settings. Before the original muffler went bad, I was gonna up-jet the carb from 112 to 115, but now with . Jun 6, 2010 · 7. Jun 23, 2006 · Its not really a "lean pop"! That popping in the exhaust under decleration tells us two things; 1: The exhaust is hot, 2: The exhaust in the pipe (which as we are not applying load to burn the fuel contains some un-burnt fuel) is coming into a sorce of oxegen! What is happening is a combo of two things: 1: High vaccume at the intake port is Jun 17, 2018 · Today as I was running her through her paces, I noticed a lot of popping on deceleration, particularly in the above 3K RPM range, so I went ahead and datalogged it. It happens more often if you still have the clutch switch hooked up, since the ECM shuts off fuel when you close the throttle on deceleration. I am working on adjusting a quadrajet on the 1972 402 chevy engine that I recently acquired. If you had high cylinder pressures, your bike would still be making power and still be accelerating. #1 · Jan 20, 2007. The incline causes the body to automatically lean forward when sprinting up the hill. Hill running is perfect for improving your acceleration. Im going through the same problem, my left one is running lean causing the car to dump a ton of fuel, I have no leaks. Raise the needle one notch (drop clip one nothc) then hold the bike at about half throttle (roll into it slowly while listening). Watch your o2 MV and if it drops to <200 mv (not an accurate/absolute value but a ballpark) you might hear popping. Backfiring during acceleration typically signifies air in the intake system of a Harley Davidson. Jan 8, 2008 · You can check the total vacuum advance just with the timing light. I appear to have solved the problem. Sep 16, 2022 · This is usually an indication that the engine is running lean. ’ Oct 19, 2023 · Backfire on deceleration or acceleration on a Harley Davidson is due to the burning of excess fuel in the carburetor’s intake port. I have Vance & Hines exhaust, Screaming eagle Air Cleaner, stg 1 download from the dealership. A clogged fuel injector, leading to an insufficient fuel supply. Posted June 6, 2010. 5 turns out now. Spark plug is completely black. If that doesn't do it then turn it out another quarter of a turn. When I’m doing very light cruising and lift off the throttle I get the pop on the exhaust. This can be caused by a number of different things, including dirty fuel injectors or spark plugs. Just picked up an '18 Xtrainer 2 weekends ago, and have ~65 miles on the clock now. Set up three cones 5-10 yards apart from each other in the shape of an ‘L. Sample Hill Workout: 8 x 20 meter hills at 15 degree gradient. When cruising along and either rolling on the throttle or punching it, have a severe hesitation. . I’m running the stock jets with 70/37 rods and the pink 7” springs. Hill work is perfect for acceleration development as it puts the athlete in proper acceleration mechanics naturally without any tools or cues. #3. This free oxygen is picked up by the O 2 sensor and determined to be indicative of a lean AFR condition when, in reality, the engine could potentially be running slightly rich. If it's not sealing around the flange at the head or has a couple pin holes in the header it will back fire on deceleration. That is not the case, from my experience. yx po ml le nd tt zj sj sq nv