This was probrably one of the best videos about small carbs thank you so much I dont think Anyone could have explained that any better video was straight to the point.. Ive been struggling with a small carb. First it was leaking out the over flow then it was backfiring thru the air intake now its bogging down with throttle doesnt die starts right up but bogs way down driving me crazy but im pretty sure after dozens of videos this is the video i needed to see. Will let you know thanks again
Best explanation yet. 2 out of four are doing this. I'm on it. Thanks. The 99 honda 300, never a problem. The rubicon 472, both have this issue. Was puzzling. Will follow.
Thank you!!! I am a complete noob and just started getting into ATV’s last summer. I am currently on my pulling carb for the 7/8 time done yesterday. the same carburetor in and out with out luck This video may be my saving grace
What kind of atv are you working on? And did you try this yet? Having problems with a 2004 predator 500 stalls at idle. I’m going to try and pull the carburetor this weekend.
im going to try this today. i have an old 1991 honda 300 fourtrax that seems to carbon plugs almost instantly. the bike idles great and can putt around in SL no problem, but as soon as your on the throttle to get through your gears, its as if the mid range power is completely gone it struggles to accelerate, and it starts to come back in to normal in the high end RPM. its causing jerky acceleration through gears and when finding your cruising speed. ive taken apart the carb and cleaned the jets, along with replaced the air and oil filters, plug and oil. somewhat fixes the problem but reverts back (my guess once the plug fouls) im starting to think the float may need to be adjusted now, thanks for the new lead!
You make a whole lotta sense bro! I'm having the same sputtering symptoms, only I have a Harley 2009 cvo fatbob with electronic fuel injection and what you just explained with the example with a carburetor is the same in nature, "Thanks big guy and be safe!
This is indeed a brilliant explanation ever to my Yamaha AG 200. By looking at this vedeo I've also checked and cleaned the main horse's nipple from the fuel tank to the cab which was being blocked by so many dirts. 2 Problems that were solved are engine dies when at low RPM or when at higher RPM, and hard starts again at about 3 minutes. ❤❤
Really liked this video. Thanks Thomas! I'm new to working on small motors and eager to learn. Learned alot. Thank you. This is the first of your videos. I've subscribed and will be checking more of your videos. I'm here because, guess what? My new to me, used ATV, is having carb issues. So again, thanks
i have the same issue with my recently purchased kawasaki brute force 750 atv. Seller told me it ran great and had the carb cleaned and re jetted by a local shop just before he put the bike in storage for the winter season. When i showed up to buy it, it spitted and sputtered like crazy and would not stay running. After i rode it around a little bit i raised the choke level up about 15% and it seemed to run fine then...the idle was great and no more sputtering or spitting. Seller was shocked and told me it ran perfectly before he stored it for the winter. I went ahead and bought it anyways knowing it was fixable no matter what and he gave me a killer price on it so I was still stoked to buy it. I so far am just riding it with the choke partially open and it runs fine so far that way at least.
colourtune plugs are handy as you can check the color of the flame which should be Bunsen blue after the choke is pulled in. there is a mixture screw under the carb usually which you can screw out a turn to get more fuel...might be worth a try. As long as the jets are the correct ones and the float heights are correct then with a clean carb the bike should run well.
Fantastic man I think you've just reminded me to clean the little holes on the jets I so got lazy and just changed the jets didn't bother to look in the little holes thanks for real man , peace
similar issue with my royal Enfield 350cc. Uses a 29mm carb, the bike tends to start dying when it's running with load at a constant throttle, say through the mid-range RPMs (2000- 3500 rpm), but post that 3500 rpm till the redline at 5500 it works fine when throttle position is constant there.
Thanks man. Just bought my first carberated bike and want to learn as much as i can about it so i can wrench on it myself. It spits occasionally, its about 40 degrees out here in colorado, and it apears to only do it when choke is all the way in... so it may just need to be dyno tuned... apparently again... not sure if its tuned for this elevation. Assumed it was and that may be a mistake as i should have asked and the dealership may have shipped it up from elsewhere.
I could not figure it out. My new motorcycle only has 200 miles on it. Came with a carburetor I have to work to get the screws off the bowl. No biggie. Yet it puzzled my on what it was doing. Did not make sense. Now it does. So, I'm going to do exactly what you suggest. I will see. If works, you just saved me money and a big headache. Thanks for your help.
That’s crazy I was looking at buying a 2008Q link 700 front runner side-by-side with a sputtering issue in the first video. I find covers my ATVs issues I have a 400 Polaris and I’ve been struggling with the sputtering issue so now that took care of that problem.
Hey man. Love your video my mate has 150cc pitbike. He had no air filter. I make him get air filter. Bike runs bad with air filter. We clean side of jets and all carb. Bike still runs OK when take off air filter. I have try to adjust air fuel mix screw but it is always lumpy in the top end and try’s stalling
Man runs perfect in every gear when you put it in reverse it don't have no power it just spits and sputters will not go backwards I also bought a brand spanking new carburetor and put it on it and it run perfect but like I said when you put it in reverse it just spits its better it won't go backwards unless you're on flat ground
Awesome video! Iam having problems with my yamaha wolverine and it's spitting and sputtering like it's starving for fuel, i bought this bike brand new and this is the first problem I've ever had with it.
Like the video and so correct, I have a polaris Razor that was cleaned and I took the entire thing apart. I started the engine and adjusted the air fuel screw along with the idle screw. The engine idles but will not accelerate without popping and spitting. I have adjusted the needle through every setting, please help
thanks i cleaned the pilot jet and it was clogged now the bike runs perfect. the carb is a new mikuni vm-32 the jet side holes were clear, but the very tiny center hole was clogged.
On my o7 Yamaha golf cart I pulled the carb to clean it... just regular maintenance now it won’t run without the choke on ive sprayed around the carb for vacuum leaks and it don’t have any the only thing I could not get out was the emulsion tube under or I guess above the main jet
Great video. I succeeded in rebuilding both carbs on my 1997 Polaris 500 snowmobile thanks to this video. Reassembled carbs on machine and fired it up. The mag cylinder is not drawing in the fuel, thus the mag cylinder is not firing. Suggestions?
I’m having issues with a 1998 vn 800 classic. After about 25 miles at highway speeds It’s back fires and dies as of its run out of fuel. I’ve researched this issue and these bikes are known to have issues with the petcock and more specifically the “fuel screen” that sits atop the petcock in the fuel tank, as this is the only filter on the bike. I’ve ordered a replacement petcock because it was the only way to get a new fuel screen. I’m going to replace said parts, as well as add on an inline fuel filter between the petcock and carb, probably only on the “main” fuel line. I’m also going to replace the fuel lines and pull the carb apart so that I may free the jets/floats/needles of any build up, as I know they have not been taken apart in some years. My question to you would be, what else if anything should I look out for and what else may need repair om order to perform properly ?
Great video , going to try it on my granddaughters youth snowmobile . One question though . How tight do you make those screws when you put them back in ?? Thanks again Greg
Great video - kicked it - straight to the point. Any thoughts on why fine gas vapor is blowing out through the air filter area on a Kohler Command Pro CV25 ? I pulled off air filter today and noticed a nice pressurized flow of gas vapor flying out of carburetor up through air filter area.
hello friend, what's the first thing to check if fuel economy is not what it used to be? can you enumerate the things I should check starting from the simplest? thank you very much
I'm getting a sputtering at low revs, low speeds. Usually at minimal throttle use. Full throttle and regular riding is fine. Model is a VZ800 (M800) 2011 Suzuki Intruder. M50 in the states. Here's the thing....fuel injected rather than carbs
Got a 2006 883 sportster. Would cut out on low speed crack pop ....everything they are known for. CV carb. I assumed pilot was too lean from factory (42) so I went thru process after complete cleaning of carb, replacing accelerator pump diaphragm and orings, gasket, of trying multiple new bigger pilots. 45, 46, 48. No change. I got a new 42 pilot, put it in. Problem now is upon throttling, it bogs n dies. If I stay off throttle itll idle all day, but soon as throttle is given, it bogs. Tried adjusting air mix, 2.5 turns out from lightly seated and 1/8th turn in from there. Gradually closing but No change. Bike has drag pipes. No baffles ran before that way just would cut out under 3000 rpms so I set out to fix problem, lol , now I can't use throttle at all it dies. I've adjusted idle as well with no luck. Black sooty smoke out pipes upon throttling, or it spits from carb airbox side of throat. Plugs fouling bad. Changed plugs, put bike back stock, 42 pilot, 175 main...float been adjusted by spec...idk what else to try. Starts without choke ez. Soon as you throttle it it cuts out bogs n dies...all this just to try to stop the low speed popping n cracking...😎. Guess I should have left it alone but I was trying to improve it. With a bigger pilot. But that failed. I believe its overly rich...from the black smoke out pipes...and fouling of plugs. About the only thing I haven't tried is shimming the needle, which I understand only richins mix so I have not done that...any ideas? Bike only has 22000 miles on it. Screaming eagle stage 1 breather....drag pipes, everything, stock....rgm883@gmail.com. appreciate any ideas. Float valve is working, accelerator pump works, no tears or pin holes in slide diaphragm....all channels blown out with light psi compressed air after complete rebuild and clean....rebuilt completely totally dry n clean....I'm lost...help? I do my own wrenching, dealerships take you to the bank even when it's a 20$ deal they take you for 300$ this has to be something simple....emulsion tube is stock, emulsion tube jet is installed correctly. ...idk...thx for suggestions...my email is above.
Did that in a PHBG 21mm.. still spits. I noticed that by adjusting the air mix screw it made it a little better, but still spits at WOT. Tried many different settings turning the screws 1/4 at a time but still cant get it right.. i had to lean it a bit moving the needle ring up as the engine was constantly flooding. Thats when the spitting started... should i get the needle ring back in the middle and change to smaller jets?? Main jet 92 idle get 50 Gilera runner 70cc. thanks in advance
Thanks for the video. I have a mercruiser 3.0 litre. I was having some bogging issues under load. I changed the fuel filter at the base of the engine, the filter just inside the carb where the fuel line attaches. Cleaned out the clear tube running from the carb back down to the fuel filter at the base of the engine. I put in new spark plugs gapped to .030. Now the boat is running better, the idle is still a little rough but the main issue is after I've been at full throttle for a few minutes I begin to hear a popping sound. I back the throttle down and the popping goes away but then at no wake speed I hear a ticking sound. I've run three cans of Seafoam through 15 gallons of gas so far. After shutting down the engine for a half hour or more the boat seems to work fine until full throttle results in popping again. Thanks for your thoughts!
Just a suggestion but try adjusting the valves. Even if that's not the problem it is always nice to rule valve adjustment out. The ticking could be a loose rocker arm and this will usually cause a hard starting issue or long crank times before starting.
@@jessesmith1181 Thanks for the idea. I am new to working on my boat this season. The boat usually starts right up. Are the things you've suggested something to do after taking the boat out after the season is over? I keep the boat on a Shore Station lift with a canopy. My only concern is that I wouldn't have the boat put back together before 9/15 when I plan to take her out for the season. Will I do damage to the boat if I continue to run her conservatively until the end of the season? Thanks!
Not sure about damage, it really depends on how far out of adjustment the valves are but if you are hearing them tapping or ticking one of them could be pretty far out. There is a 15 minute ish video on you tube just for the mercruiser 3.0valve adjustment. So you know exactly what you are in for labor wise
The popping you are describing is it a backfire through the carburetor or out the exhaust possibly? Trying to figure out what u mean when u say popping at full throttle
@@jessesmith1181 The ticking becomes un-audible after about 3-5 minutes while running at no wake. However the cycle repeats itself (popping then ticking) if I go to wot after the ticking stops.
Good video, no look at me, just the info. I dislike videos other way around. I subscribed, I'm a bit of a wrencher myself and I'm bad about forgetting something I already knew. Thanks for posting and we'll explained.
I have to give mine half throttle to start. The auto choke works fine, so I guessing its the slide. I have no filter on it,the filter I had on it got destroy by the carburetor when I buy the carb new, haven't put back one yet
After changing carburetor and air cleaner filter on my 1996 Polaris sportsman 500, I have a cold natured carburetor but runs great after about three minutes of warm up but every time I go in reverse it conks out. every single time no matter how slowly or how fast you reverse it comes out works great in forward makes no sense. What could be the problem? Mike Griffin Georgia
Hi Thomas, I have some questions I'd like an answer for. I have 1995 summit 670 with vm40 mikuni carb, everything is squeaky clean almost spotless in there everything new except for needle jet and needle. (needle valve, seat, main jet pilot jet, gaskets) and had it set up to factory such as round slide opening air screw and idle screw float arm adjusted to 19.6mm bottom of the arm to face of carb where gasket sits. carb was keep flooding I tried to have float arm to 20.5mm didn'tdo it. flipped the arm set it to the height still flooding. I took the slide out and excessive amount of fuel was coming out from main jet( throat I think), thru jet needle tube. I blocked the jet with needle and tried again and breather hole and such was puking out fuel. why would it be keep flooding? and its happening to both of carb and I dont know if floats will go out at same time
Hi. Maybe you can help me out. I have 2010 Kaw Bayou 250. It cranks and idles fine. The first thing I noticed is after first starting and letting warm up, it idles fine but if I rev it from idle it cuts out....I had to slowly get to that full throttle. Then when took for a ride it sputtered a lot at high throttle. I cleaned carb. I did notice that the float was high, I adjusted that , removed jets and cleaned ALL holes....running same way. This has the bottom front fuel/air mixture screw. It has spark but not a bright blue spark, more of an orange spark. I am thinking I may need to raise main needle or adjust fuel/air screw out for richer? Let me know what you think or anything that may help. Thanks
Iva a Kawasaki KLF 300 that won’t start !! It was originally just getting slower and slower to start, so I stripped carb and replaced all needles and jets etc , I found someone before me at left in too many rubber rings and washer on pilot air screw jet , but now after re-assemble it won’t fire at all ?? Just seems to back fire through carb a little bit , I’ve good fuel and I have spark , I’ve tried spraying into carb while cranking to see but still no fire ????
I have an issue. i got a 1978 kz650b, it has a 4-1 pipe which is basically straight pipe since it was drilled out before i got it and since rusted, it ran really weak so we bought k and n pod filters aswell as upping the jet and pilot jet sizes to even out the mixture. the #1 cylinder and only that one will backfire out the carb every few seconds at random, the carbs have been cleaned twice, pilot and main jet are new and it ran consistently (however weak) before and i cant find a solid answer anywhere. in addition to that ive also been told that when it was parked (35 ish or more years ago) it ran fine however the original carbs were misplaced so new ones were bought, they fit and worked before the jet upgrade but i have no clue whats wrong. please any advice would be helpfull.
I have a 98 Kawasaki Lakota 300 doing the spitting sputtering and backfiring idols perfect when you hit the gas doesn't want to move and spit and sputters
What would the problem be u think on a quad bike when it’s bogs down after u leave it idle for a little bit or doing slow speed and the cooling fan kick in when it’s at temperature only plays up when it’s get warm
I took apart my carburetor yesterday and when putting it back together I found a gold screw and didn’t know where it belonged 🤦♂️ now I know 😂. Gotta take back apart
Having a similar issue. 82 Kawasaki csr 305. Starts right up, idles great, revs great. Go to take it down the road, not rideable. Bogs down and has no power unless wide open sometimes.. any help appreciated!!
So, on one of my floats, the arm broke off, the one that the bar goes through to hold the float in place, any ideas? or can I run it like that hanging a bit? im also running on 1 cylinder, could this be it? or do I need to do a better job of cleaning the carb? one more question, what's the easiest way to check to see if im getting fuel into the head from the carb? do I just open the hole and rev the engine to see if it's spraying? I have strong spark
Have a 400cc BMS 4x4 with a Honda looking engine (Odes engine)...Always a had starter but now won't start and coughes when trying...even won't start with starter sprayed.
Great Stuff!! On my intek motor of my lawntractor, I will have my throttle down at idle and in seconds it will rev up and will keep revving even higher, to knock it back down before i blow the engine , i step on the gas and will go back to normal . when i am driving it stays normal but when i stop and leave it idle it will do it again. Would like your comment on what you think is going on .
The idle circuit is too lean. Turning the fuel screw clockwise will richen the idle. Counter-clockwise will do the opposite. If it has an air screw, they do the opposite, clockwise will lean it out. Hope this helps.
