How to diagnose a carburetor problem in less than 5 minutes 

►► Check out my step by step video guides to cleaning carburetors -www.themotorcyclemd.com/pro-carb-cleans

A nifty trick I learned from my dad working at his Oilfield and drilling rig Instrumentation repair shop to clean metals, especially Aluminum and Brass, is to use a container, a coffee tin or plastic 1 gallon ice cream bucket or 5 gallon bucket for larger jobs, of suds-free Ammonia with an aerator/bubbler, I use an aquarium air pump hooked to a short length of copper tubing, with the end pinched, make sure it's suds-free or you'll have a huge bubbly mess. Let your parts "bubble" overnight and you will have a hard time telling new parts from old. The equipment we work on is sometimes 50 years in the field and been chugging away almost everyday of it's life so you can imagine the condition of some of this stuff. I grew up working in his shop and ended up going into automotive, I'm an ASE certified technician for over 15 years now and I've never seen car parts, in their worst condition, even come close to some of this rig equipment and all it takes is an overnight in this to perfectly clean them. It's insane how well it works. I have seasoned mechanics ask what I do to clean my parts, especially carbs, and I never tell, this is the first time I've ever shared this, try it, you won't be disappointed.

We have special starter fluid in Australia, it's called "Start ya Bastard" good stuff. #LoveYourWork

I applied this method w my boat that was sitting for 10 years. Started right up. I'll be Replacing the carb and fuel pump, and draining out the old gas.

I saw a number of your other videos before I saw this one. They are all GREAT. And now I know why. This first video is excellent. You are a natural, Cody! Thanks for all your efforts in helping out the community, especially newbees like me.

Thank you so much for your time on making these videos I've learned so much from you bro, really appreciate it!

I stumbled across your channel whilst procrastinating at work and must say you are brilliant. You're one of the only RU-vidrs that really explains things in full detail. I have a CBR900RR '99 model. We all know how an inline 4 should sound, and how a V twin sounds. The problem I'm having is that the inline 4 engine is firing like a V twin (in my opinion). I've cleaned the jets out thoroughly, done a compression test, and all i can think that's left is the mixtures/balancing. Your newer videos regarding balancing and mixture screws have helped me understand what to do and how to do it 10000% better than I knew before, so THANK YOU! Keep up the amazing work, and I hope to see more videos soon!

Great video buddy, compliments!

Hey Bro, Great advice...worked like a charm. I was getting ready to pull the carb apart!

Hi! I appreciate what you explain about using the choke as a tool to diagnose a carburetor problem. Very useful, thank you.

Ohh lord, i have been researching this for hours. This is exactly what ive been experiencing! My bike has stood along for 10 years. And finally am I going to get it driving again, ill do a carburator check and clean tmrw. If this works ill be thankful to the greatest, im already am. Thank you for my hopes.

Hey, thanks for the video, and easing my mind. I was hesitant to try and use starting fluid to see what was up with my 92 FZR600. I know from working on cars too much is a baaaaad thing. Anyways, got my ride started, but having idle issues. At first, when cold, it wanted to always die, feathering the throttle can keep it running, then when warmed up it wanted to race without any additional throttle. Now it doesn't want to idle at all regardless as to how much I turn the idle adjustment screw. I let my son take it in to his high school shop class, the bike had been sitting last 6 years, in the hopes that with supervision he could get the carbs all cleaned up and everything back in running condition. I am not sure how deep he went into the cleaning aspect. I was suspecting a vacuum leak, but with it running I used the starting fluid and hit carb to intake connections, and vacuum lines with no change in the idle so that tells me that part is solid. Now I am not sure where to go. Any help would be greatly appreciated. Thanks!!

Very good video helpfull and simple.. good job dude thanks. Looking forward to more videos

Great video, look forward to more.

I'm new to bikes and this is very easy to understand. Thanks dude.

Thanks bro I have a 2006 gsxr and had to do the regulator and stator and you made it easy

just subscribed in an effort to remedy the suspected dirty carb on my 08 ninja 250...you've got the yt personality that I can appreciate. keep the channel going in its current direction. thumbs up G.

This is why I subscribed simple and straight to the point. I only wish i could of found your video sooner before getting rid of my old bike

Thank you for the vid. Bike sat idle for a year,, got a new battery and it still won't fire. But I'm going to try this and hopefully it will give me somewhere to start

It is currently September 19, 2018. I bought a 2000 suzuki bandit 600. Paid 500 for it. Previous owner said it was a fuel probably. Came home to start and it kept cranking but couldn’t figure out why it wouldn’t start. Then finally it took 4 days to find this video. And holy shit , once that starter fluid hit those carbs! It started!!! I literally thank you! You don’t know how much work you saved me from. Now time to clean those carbs!!! Thank you man!!! 🙌🏽

Same here I appreciate the info thanks brother we need more honest Machanic’s like you much love from El Paso Texas 🇺🇸🦅

Thanks for this!

Your the best bike mechanic on all of RU-vid man. Thank you

This video is going to help me this week... Buying a kz550 that's been sitting for five years lol.

I'm having trouble getting my 98 cbr600 started, First thing I did was change plugs, it gave it a little extra "umhf" but no start. I'm definitely going to try the starter fluid now

No nonsense here! Thank you!

This video is amazing, worked for me perfectly when i lost all hope, i cannot thank you enough

Hi Cody! Thanks for the great vid! i have a 78 cb400t. I think it's the same as the hawkii. im running the carbs of a 79 cm400. stock 78 cb jetting is 75/110. stock 79cm is 70/112. the common belief is of course performance can be improved b/c factory shit is too lean. i stuck the 75 in there, so im running 79cm carbs primary up from 70 to 75, and 112 secondary. When i cold start it, it starts out good then roars way up to high rpm (dead tach). choke doesnt do anything when thats going on, i tried winding in the idle screws to 1/2 a turn out each and that made no difference either. I could just put the old jets back in, but id rather understand wtf i did here. why are my primaries causing high idle? 1 carb was leaking, so i fucked around with the float to raise the needle a little. cant see that doing it either,but obviously im missing something!! Thanks bruh!!

My vmax had one carb that took forever to fire up. My problem was with vboost working on it myself was scary. But I'm sure I could have done it. Finally got to point where it wouldn't fire up at all. 450 bucks later they're all running fine now. Multi carbs are a science to be sure. Hope your channel works out. Good luck.

best ,thanks love it

great video, how do you do this with a kick start?

Awesome video! I have an 82 yamaha seca that will not start. New battery, plugs, wires starter rebuild. Almost had something once but just does nothing. It'll turn but no fire. Any suggestions??

Thank you for this video. Hoping you can help direct me. I have a 2009 Honda VT750C2 with 20,000 miles. I ride nearly every day and have been doing all the maintenance. Recently I've had an issue where the bike won't turn over. Before I followed your tip, I worried I had run out of gas, or the petcock vacuum was stuck, or maybe the carb was sticky or something. I noticed that I had the fuel shut off so I figured I had run the gas in the line out while I was letting it idle on choke to warm up. I bought a vacuum hand pump and confirmed the petcock was working correctly. Then I found your starter fluid tip and that worked great to get my engine started again and the bike has been running fine for a few months. Today, the same thing happened with the starter, but again I have a full tank of gas and I didn't have the fuel shut off this time. The starter fluid into the carb got it started again and it is starting again on its' own, but now I'm wondering if there's a deeper issue I need to look into. How would you diagnose this?

Good shit bro. I'm an L1 Master tech in automotive n i recently had the $$ to finally get into bikes as much as i always wanted to so mechanically/electrically im already inclined but to know each component and different adjustments/tips/tricks u name it, i want to learn it. So even a very inexpensive & simple solution as this is great. Make some videos on idle adjust screws, maintenance, brakes, carb cleaning/rebuilding/symptoms & hell even an engine tear down if u have a scrap motor, and i'd def suscribe n spread the word. Take it easy keep it up

Good advise very helpful

Huge thanks to you Cody. saved me a lot of pounds to show my stupidity to some garage ;)

Thanks for the information

Love your vids brother. This reminded me of my issue im having kind of. Im battling the issue of bike will start and idle on and off choke perfectly, but the moment I give throttle, it wants to die as if the main jet were clogged but its not. Although if I spray a couple squirts I can rev it to normal rpm. I'm so confused cause I triple checked the carbs and jets and diaphragms and needles and all and it'll only rev to normal rpms if I spray it while running.

Ya boi just earned himself a subscription. For real though, it's awesome that people put up all this content. I didn't necessarily need this video but if it helps more people get into bikes, even tangentially, it's awesome. The only bad part is that $500 bikes with dirty carbs will be harder to come by :D

Hi. Great video..if i have spark and am spraying some starter fluid straight into carbs with no luck what could the problem be??thanks

great job man!just subscribed

Hey! I would have one question: I have adjusted the float level on my carburetor, and replaced the float needles. Now after the winter the bike will not start. I am wondering whether it is due to the earlier modifications - I even tried a bit of starting fluid but it did not start. Does that mean it is something else than the carbs or can it still be the carbs but they are way too rich?

Thankyou for being the only person on youtube that speaks english

Cody thanks for the great videos you make! I have friend with a 2004 (?) Suzuki SV650 that has an issue whereby it starts fine but once warm starts to stumble. The bike sits for prolonged periods so maybe that indicates the carbs are gummed up but why would it run fine when cold? Seems like that means the idle circuit is fine but main jets might be an issue. He’s having a hard time finding a shop in the Santa Cruz area that will work on carburetors. Thanks again.

I've watch all your carb related videos and subbed. I don't think I they resolved my issue yet. I have 1993 suzuki katana gsx600f. Its got a stock air box and stock header. But the pipe is off of a 2004? I'd Imagine its basically the same as stock. I took down and cleaned all the carb parts last week. I put new fuel in it also found a couple vacuum leaks. All good (so I thought.) after filling up then about 100 miles (last year I was getting closer to 150) I ran out of gas. Ok that's odd but maybe I was running it hard or something. I get it home after filling the tank again. The next morning all my fuel had drained through the carbs into the crank case, cylinders, filter box. I take it all apart again and clean everything. I took extra time to inspect the float valves. Didn't see any issues. Adjusted the floats and double checked it was all clean. Put it all together start it up rode across the street to the gas station fill it up and suddenly starts and barley will idle at WOT... It dies and won't start. Walk it home about 5 min later I have the air box off. It's full again. Taking it apart is getting old. Ordered a complete rebuild kit and dyno jet kit. I put the stage 3 kit in that's supposed to work with the stock box. Now it will idle perfectly fine but it will not throttle up at all. Then it all the sudden decides to red line and stay there till I can get the kill switch turned off. I'm assuming I'm getting too much fuel. I followed all of the instruction on the kit and am completely unsure where to go from here. Do I put the stock jets or the stage 1 kit that came with it in? With the stock main jets it wouldn't quite idle till it was warm. I know the mains are not supposed to affect idle? So why will it idle with the bigger jets (same idle jets)? Is it related to the idle air screw? Any one have a good place to start?

Hey, I have a honda cb250 jade motorcycle, problem is always are all spark plugs are wet, so tell me what i will do for this.

The first thing most new buyer's want to do is tear the carbs apart before checking all this other stuff, and then they have a long list of possible woes to sort thru before they even know if all else is okay. Great place to start diagnosis.

Great Video cant wait to try this on my HellKatt!!!

After I rejetted my bike (I put a higher flowing exhaust on it) it developed a hesitation at high rpms (right around 8k) and it stuggles to go past that point. The bike idles fine and just cruising around it runs fine. Before I rejetted, the exhaust popped a lot on decel and when I closed the throttle because it was really lean and it still pops on decel after rejetting but not as much, but more than it should. Could this be caused by a dirty carb? I checked all of the fuel lines and vacuum lines and breather hoses and everything's good. I'm thinking maybe the passage for the main jet and/or the main jet itself is clogged? This is my first time ever messing with carburetors. My bike (2007 Suzuki gs500f) has a pilot jet, a mid jet, and a main jet. The bike did sit for a few months for winter with fuel stabilizer in the fuel system and I didn't really do a good job with cleaning it when I rejetted because I figured the fuel stabilizer did it's job. I'd greatly appreciate some feedback!

Cody, great stuff. Are you able to do a vid on a 2000 Intruder 1400? The reason I ask is that for the novice, (me), I struggled with a seemingly simple compression test. But it went out of bounds due to the unknown de compression valves, and that they were out of sync. Plus one was running 25% open all the time. I had bizarre psi's. But after a long struggle I understood this and adjusted both to fully open, ( which solved for some a starting problem, like a dead battery). So if you have time. Appreciated.

Do you guys know if there is any carburator Kits for rebuild our carbs? TIA!

Hey man, love the content and can I say what an epic peice facial fro! I've got a suzuki ts250 which I have just fitted with a pod filter. I've upped the main jet 3 sizes, but when the bike starts, it revs for about 3 seconds then cuts out... What might be the issue?

Hey, i just wondering if could help me diagnose what could be happening to my bike. What it feels is like the bike is running in a bumpy road not agresive, that eventually just go away, the shake is really weird at first i thought i could be something with the front tire beacuse i feel it more in the front handlebar but the shaking comes and go. Any ideas waht could it be?

I've got an issue with my kymco agility city 50 it was running fine and now won't start

Hey I just purchased an old KZ440 and I'm getting a miss at 1500 rpm's. The guy I got it from said it may be the boots or diaphragm. He suspected there might be pin holes in the diaphragm. Does that sound plausible to you? The miss will cause it to die if I don't give it more gas. Anyone got any idea's I would surely appreciate them.

Got an 86 Honda goldwing GL1200 ASPENCADE. Doesn't like to idle without choke and will stall if accelerated. Can spray starter fluid and revs up. Suggestions?

Hello mate just quick question have you ever use Seafoam for cleaning carbs or any other chemical substance and what is your personal opinion or experience, you are big help and love all your videos cheers

good vid, im having probs with my zzr1100 carbs, recently removed the carbs for a clean, ( ultrasonically) , checked every component on all four carbs and after the clean every part was prisitine, checked the diaphragms all looking good, float hieghts checked and also fitted new plugs, set the air screw to the manufacturers setting however im having running problems now, its misfiring on cylinder 4 and lots of backfiring off idle, the bike starts fine with a little choke, but after about a mile down the road it drops on cylinder 4, I did balance the carbs when I put them back in but cant seem to sort the misfire??? any suggestions would be greatly appreciated, sounds like you know your stuff with carbs :) thanks mate

When I used work at a repair place to fixing mowers, strimmers, chainsaws ect. I had a trick to starting engines. I had a trigger spray of petrol or two stroke mix in a trigger spray and would spray directly into the carb intake to see if it would fire. When I bought my first non running motorcycle, A 2004 Honda Varadero XL125V that had been left stood for over two years with a full tank of E5 petrol, I sprayed fuel into the carb intakes and it started but wouldn't run. I opened the carbs to find the float bowls dry but had a green coating and the jets were completely blocked. I didn't have the correct jets to hand so I fitted the next size up and it ran fine.

Upon wide open throttle, my car intermittently gives severe jerks/misfire. This started happening after rebuild. What could be causing the issue? Can the large jet cause this problem?

Hey Cody, quick question. Have an XJ650 1982 Yamaha. Started my motor without the pod filters, used the hand cover technique. It started fine and idled fine. Then I put on my K&N pods, now it's having trouble to start. What's the cause?

As always great video , my 4cyl motorcycle (05 Yamaha royal star ) it will take a long time to rev down and is also using a lot of gas , where should I begin? Check for leaks with starting fluid ? Thanks in advance…

Great video brother, got problem with my sportster where it cuts out at idle but only when it's hot/at operating temp.

thank you

Sick video

Great video bro

Thanks again!

Tell me this, my 750dc shadow has rebuilt carbs new plugs all new gas line floats set etc all things to make a sitting bikes run. She will crank and idle but pop if you give her gas pop pop, i am at a loss and about teady tk take the 12 gauge to it and be done. Any suggestions?

perfect presentation. strait to the point. well done. liked and subbed.

Hey buddy, I hope you can give me an idea on an issue I have... My bandit 1200 has a cylinder which doesn't seem to ignite (exhaust pipe of that cylinder stays cool) A symptom I see is that I can't blip the throttle, I have to gradually increase gas else it sounds like the engines dies Sound wise it runs sometimes smooth, sometimes a little rough, Any leads?

Hey man I have a ninja 250 that was sitting for about 2 years at first it would shut off on idle when giving it gas. The carbs were cleaned as well as dumping the bad gas and now it runs and doesn’t die however there is some power loss I have to twist the throttle all the way down which is unusual. The bike just feels different. Do you think changing the spark plugs can fix my bike?

The last dirty carb I successfully cleaned was burning rich, with black plugs (both plugs in a V twin) and blue smoke out the exhaust. I did a little head scratching on that one. Why would a dirty carb lead to rich combustion?

Great video I have a problem here in the UK My wife's xt225 is a pig to start in cold weather It will start after 5/6 attempts but is frustrating Will this method be the same with the starter fluid Keep doing what your doing as you do it well 👍

Bought a gs650e. To save a backstory, could the bike still function with all stock jets, but with an emulsion tube and the jet needle for an 850? I'm having a lot of trouble with the idle and determining whether it's too rich or lean.

I have an old kz650 with mikuni CV carbs and it only runs when I spray starting g fluid into the carbs it'll rev up high then die, and I too lean? Or possibly a clogged jet?

Hey mate I was just wondering what would be a good air/fuel setting for a keihin 22 carb on a honda cb100 ? Thanks

Hi Codie . I have a issue 4 cylinder triumph 1200cc. 1999 According to the exhaust gas analyzer, cylinder 3 & 4 at idle are at OEM recommended figures (3% ) co. 1 and 2 are running at 5.2 % . But theres no more idle adjustment left before it cuts out. I'm thinking of dropping down on the idle jet size. ??? My problems is which cylinder is it ? 1&2 go into one exhaust. . What's the best ways to tune each carb . And yes they all have been ultra sonic cleaned and fully rebuilt with gaskets and new seals and all that.. Do older bikes tend to run a rich mixture and a very high hc figure. ? My victory runs almost on fresh air is it possible to set up an older bike to run more eco friendly ? Sorry so many questions.

That's great and all and it worked for me but what happens if you take apart the carbs clean it End and it doesn't even start with starter fluid anymore like it did in the beginning If starter Fluid worked But didn't after the cleaning?

I've rebuilt my carbs on my 98 750 Shadow, didn't mess with syncing. Now I have a high idle and very poor response. Suggestions please. Thanks

great vid thx

hey got a question MD i have a 125 hongyi diablo prince also known as hongyi giantco my question is why does my bike ^drag^ when im in top end of 3rd n 4th she drags back and vibraters alot any idea

I have an old trail bike, and it was running till I dumped too much marvel mystery oil in the intake. I've checked to make sure the carb is working, and it does, I can get the engine to run by dumping gas into the cylinder, but it just takes off once it starts. If I let it, it will probably rev until detonation. Does have a suicide throttle thing going on but I can see that the throttle is completely closed. What do you think is going on?

I cleaned my carburetor on my scooter, but when I rev, the idle revs down slowly or hangs up. I already checked for leaks and it doesnt have any. What do you think is the problem?

So i have a 81 cb650c ive cleaned tje carbs and put it all back together. When it starts it iddlesas at about 2k and then after warming up it goes to 5k and bounces around alittle. Ive disconeted the throttle cables the choke is not on have the pilot screws at 2 1/8 turns from being set and idle screw not even touching the idler. Ive bench synced it and I have no vaccum leaks that i can detect and all the jets seem to be not clogged. Im unsure where to go from here.

Awesome work man. Question, my bike is backfiring on deceleration, all else good. The mix screws have no effect on idle! Either one cx500 what could be wrong?

I have a 1980 Honda CM400E. Lately when running in Neutral or 1st(don't know beyond those gears), it keeps dying if not applying throttle. Sometimes it dies when initially applying a small amount of throttle. It dies again and again, and then drips gas heavily at the bottom of the bike. It appears to drip from a bolt down below. Do you have any ideas for what this might be? Thanks. I live in Cherry Valley, Ill., and I am looking for a decent mechanic. Thanks.

I have a CB350 that I got a few months ago. It runs rough. Carbs are clean, valves are adjusted and everything. It stutters in idle and mid range, can't get it to idle at below 1100 without it cutting out. How do I tell if it's too lean or too rich? Also, how do I go about tuning the carbs and syncing them?

I have a honda cbr125 2005 carb model revs up when hot after 6 or7 miles any ideas

I have a 1995 cb750. Starts and runs fine until i get to 4th and 5th gear it starts to sputter like its losing gas or maybe not enough air?

nice job

my problem of my cv carb how to diagnose it properly. from idle to full throttle its run smoothly to its rpm sound. but you test drive and reached the rpm 5thousand and 6thousand the slightly slog the rpm power. but when exceed 6_thousand back to normal good acceleration and best run... whats the problem of it in between ,5&6rpm???? tnxs...

hi man. i'm having problems with my carburator. i guess. it stalls when i get the revs down. when im going at high revs it goes well as soon as i get it to 2000 rpms it stalls and stops eventually. to get it going i fiddle with the choke button and then go . what is the problem with my bike ???

It could also be a restricted fuel feed line right? Not the carb?

Hi my name is Julian i wanted to ask you if you can possibly answer me about my 1967 mustangs carburetor. It has been sitting since 1976 and i ended up replacing the distributor, spark plugs and the starting solenoid I went to start it for the first time in 40 years and it turned over great and running like a champ plus it has good compression . Ive been running it everyday for at least 2 months for 45 mins and starting with no trouble but now its firing and its trying to start but it wont turn over and if it does turn over it runs like its misfiring all over the place and if i give the gas pedal a tap the engine stalls out. Does this mean my carb is bad?

Hey! thats the same bike I'm working on right now! '68 Honda CB350... just bought a CB360 / 350f disc brake front end for it. So that should arrive soon. It was (and is!) my first road bike, so I don't think I'll ever sell it.. i already have most of my build mapped out.. it's just being able to have enough disposable income every fortnight compared to my paycheque. Shipping from the States to Australia ain't cheap! Oh yeah, it wouldnt run for anything. tried everything. Ended up getting finding an original keyster carb kit in Germany. P:ut that through the carbs , and cleaned everything, and changed the jets to new ones and she fired up pretty much first time and ran like a champ. Gonna put new ignition coils on it soon, as the current ones are looking pretty ratty. Electronic ignition would be nice, but I can't afford that right now.. I love my cafe racer builds!!

Hey , not sure if you can help me out but I bought an older chinese kids atv and it wont start without starter fluid . But when sprayed into the carb it runs fine and will restart when warmed up no problem . It idles kind of lumpy and burns a lot of blackish smoke . Everyone says it's running quite rich . When I adjust the air fuel mixture screw it basically does nothing until it's all the way in. That's when it just dies . I can basically turn the screw all the way out and it doesn't seem to make a difference . The idle screw seems to work fine in increasing and decreasing the idle but the off mixture makes it idle rough regardless. Any advice or opinion on the matter would be greatly appreciated. Love your videos . Thanks

My yamaha Rx135 current is fine in the spark plug. But not starting. After looking you vlog I feel my carb is not working well.

my 650 vstar spits and sputters and shotgun backfires on deceleration, stock exhaust, clean jets , new plugs. any suggests?

Cody in my Vt1100cc ,,two valve in each cilynder,,,,one is very clean and the other one is black whith carbon,,,,,,What's tha mean?

Hi mate, when I'm riding my mc19 it will only get to about 4-5rpm and then bogs down and no power. And most of the time die when I pull up at a set of lights. Could this be my fuel pump? I have read on other forums it could be the fuel pump. Thanks Liam