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Episode 1 Carb Clean EX250 Ninja Motorcycle carburetor cleaning

Follow along in this 8 part series while Quentin walks you through the proper techniques and procedures to do a carb clean on your Japanese motorcycle.

Another cycle for life video this time what we’re going to do is we’re going to take a bike that i picked up as a daily commuter i chose to go get a very inexpensive bike that would last a long time with very very little maintenance but i only live a mile from work so i didn’t want something with a lot of power i didn’t want something big for what i’m doing right

Now for the purpose that i have this little ninja 250 that i got for 250 dollars because it doesn’t run right it’s perfect it needs a carb clean reason i know it needs a carb clean is because i started it on starter fluid ran it on the choke it runs fine on the choke at idle and then as soon as you take it off the choke it either wants to die or won’t take throttle

That’s a telltale classic sign that the pilot jets aren’t flown enough fuel and it needs a carb clean so what’s the purpose of this video this video is a carb clean video and i’m not doing it work sure i’m gonna do it just at my place i rented a little mobile home trailer out in the mountains so cheap little place to stay i’m just going to do it out here on this

Driveway and i’m gonna do it with the same kind of tools that you guys on youtube would have access to yes at work i have you know presses ultrasonic machines car lifts tig welders mig welders you know i’ve got a snap-on box that’s literally bigger than this 19 g20 van well maybe not quite as long but my snap-on box is almost as long as this van so you know you guys

Don’t have access to those kind of tools work in working at home if you’re watching this video so i’m going to show you the tools i’m going to do this job with just a basic old beat-up set a bosch i think this was a lo special at some point and that’s my old brace box i’ve had for i don’t know i’ve had that little tool box for 35 years i started out of that little

Tool box as a teenager so with a very set of tools and a very humble environment i’m going to show you guys how you would do a carb clean if you were at home so the first thing you need to do on almost any street bikes to do a car clean is you need to get the gas tank and the seat out of the way so this bikes real simple to get the seat off of bam done just like

That the other thing you want to almost always do whenever you’re working on something disconnect your battery pull it out throw it all charge so yeah i got my battery charging off this ninja 250 here i pulled the battery and the toolbox out of this little section right here behind the air intake for the airbox and when you pull this rubber boot yep there they are

When you pull out rubber boot it exposes bolts down there and then this lifts out and this slides back and that allows you to slide this whole airbox filter and box assembly back that way away from the carburetors to give you clearance to slide the front of the carburetors out of the boot the biggest challenge on these old things is they don’t use real proper band

Clamps they use these cheap little springs right there i don’t know if the cameras getting that or not but see that cheap little spring on the other side doesn’t even look like it has one it’s either broken off or already falling off man what a junky way to do it so when i put this back together i’ll either ban clamp it or something to figure out a way to get that

To seal better because no matter how clean your carburetors are no matter how spotless you get the pilot circuits and the correct jetting and everything if you can’t seal the back of that venturi to the airbox you’re not you’re gonna have air leaks and air leaks are gonna be throwing your jetting off which it’s going to give you the same result as a carb that’s not

Clean so the whole idea of cleaning a carb is to get all the jets and passages clear to get enough fuel through to mix properly more is not always better a lot of people just put bigger jets in thinking oh well i’ll just put more gas in and that’ll make it go faster no it doesn’t an engine is an air pump not a fuel pump so as that engines running its pumping air

There’s a certain amount of air that it’s pumping and that’s fixed that’s defined by on a four-stroke displacement cam you know cam lobes and cam timing compression there’s a whole lot of things that factor into how much air and engine flows and then the carburetors job is to give that engine the right amount of fuel for the maronite air that it’s flowing so when

You modify an engine it’s often common you need to modify the jetting to go with it when i’m road racing ninja to 50s i pull the airbox is completely off to get as much air flow as i possibly can which is how i get ninja to 50s to put out over 40 horsepower i run those carburetors wide open with no air boxes and of course i have to go up 18 20 22 sizes in the jet

Sometimes and put completely different needles in them to get them to even run so as they as i’m not trying to digress into racing i’m trying to keep this video about car cleaning so why am i bringing it up well because if that air boot is not properly seating with the back of that carburetor like it’s not you can see i’m moving it back with my finger it’s not

Sealed on there there’s massive air leaks between that boot and that carburetor and that alone will cause a condition that makes you think you need a carb clean whether you need one or not all right next little trick on this job is you see these rubber nubs for the gas tanks man if i had a nickel for every time i was chasing these down in a shop somewhere take

These off if you go and race and llaman bond them inside and glue them on the frame so they don’t come off if you’re not going racing and you’re not worried about it just put them aside and make sure you don’t lose them but seriously if you try to ride down the road and i’ve seen clowns do this before if you try to ride down the road without those bumpers and

That gas tank bouncing on that frame like that it’ll crack your bodywork up because then the body works taking all the force of the tank the weight of that gas and gases i don’t know seven something pounds of gallon you get five gallons in there you have forty some pounds bouncing around you want that weight on the frame you don’t want it on your plastic so make

Sure you don’t lose those little rubber bumpers the next trick was i had to get the clutch cable which runs down here like this to the clutch i had to get the clutch cable out of the way to get to the carburetors and get to the carb cables and get the carbs lit out so sorry i didn’t show you that on the video if you don’t know how to take a clutch cable off this

Is probably over your head anyway no offense you prot shouldn’t be doing it so not to be mean but seriously so you got the clutch cable out of the way the next steps gonna be throttle cables we got the airbox totally loose okay next step is the choke cable there you don’t even need any tools for it it just slips into that fitting right there and pulls that cable

Back so you just close your cable to the alway extended position and then pull it back and that acts like you’re pulling the choke cable on just pull it back and when you get it enough out of there to slide it out of there and then unclip it off and then unclip it off the other end okay so choke cables next all right we got everything disconnected we got the fuel

Lines disconnected the choke cables disconnected we got the airbox lid back to give us as much room as as possible i wish i had more but people kawasaki or mean so it’s not the next thing are these manifolds right here i loosened up all four for you guys see that i got them all for loose a lot of people try to erroneously just loosen the ones up on the back and

Then slide the carbs back and that that leaves these boots in the way for you to have to fight to get them off the bike so i loosen all four and then if the manifolds want to pop off the front let them pop off the front whichever way is going to come easier let it let it do it whether you’re fighting it on the back side of the front side they got to come out of

There so just loosen all four clamps get the manifolds out of the way first if you can if you can and then slide the carburetors out this is a very unpleasant not-so-happy part of this job it’s packed in there tight and a lot of rubber on the back side has to flex back to give you room to get the carburetors back and a lot of rubbers got a flex on the front side

To turn those manifolds and twist them out and you got metal clamps jangling around all in the way so yeah this part is not fun left manifold out of the way okay and there are the carbs this vent line is just a vent it just dangles down you don’t want it to dangle on top of the engine where the starter is i’ll show you what i mean i’ve seen fires start this way

There’s your starter right there right there connection that’s a positive cable going to the starter that can can maybe shouldn’t can arc out sometimes if another piece of wire or another piece of metal or something were to hit it or occasionally i’ve seen defective starter spark from the inside and at this vent is dripping fuel because they do the vents do drip

Fuel fuel gets hot bubbles up drips out you don’t want that building up on top of your engine there and creating a fire hazard so it’s important to have this vent there and have it going out beyond the back of the engine case and down to the ground yeah that’s that’s the removal other carburetors the next step is going to be pulling the bowls and pulling the slides

Out checking the diaphragms and prepping them for cleaning and i’m done with this phase of the project i got them out of the bike so i’m gonna turn the camera off and next time i see you will be sitting somewhere else on a workbench where i’m taking these carbs apart and preparing them to actually clean them alright god bless you

Transcribed from video
Episode 1 Carb Clean EX250 Ninja Motorcycle carburetor cleaning By CycleForLife