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125cc dirt bike carb tuning

125cc dirt bike carb needle tuning

Hey youtube this is g factory 101 here and thanks for coming it watch what i’m doing today today we are looking at what’s happening with our carburetor our one to five fun bike dirt bike which is a great bike but it’s doing what a lot of people have said he’s called bogging out and this could be caused by a number of reasons first things first we thought we needed a

New air filter so we’ve got one but we’ve got a splash guard on it because of where we’re riding it’s quite where the minute so we’ve cleaned the car about cleaned all the jets out and one of the things i’ve seen lots of videos to do with bogging out he’s setting your car a needle which is this little baby get a focus on that one yeah never get focus on this phone

Nice okay anyway so people adjusting from the factory settings of this needle to ease for the temperature of your ride now i put this next to this particular spark plug picture because what you’ll notice is i’ve got a book of spark plugs and how they fail out foul-up and it tells you why they foul up and one of the most interesting things i’ve learned about small

Engines and small carburetors from lots of youtube users is what your spark plug is doing tells you so much about how your engine is running when you don’t have ecu’s etc electronic management systems and then you’re relying on basically mechanic knowledge so in my book it tells me that what my plug is doing which is black and is dry black and such deposits leading

To misfire which we have caused causing a weak spark and it’s caused by an over rich slash fuel mixture and faulty choke operation or blocked air filter so the air filler and the choking system on the carburetor is working fine so the next thing i’m gonna do here is adjust the settings on the needle there’s plenty of video showing you how to get the needle out so

I’m not gonna do that so if you just type in carburetor needle it will show you how to get it out but basically there’s five settings on here and at the moment he’s setting the wrong way so what i need to do is i need to adjust the needle setting higher up and i’m gonna go for the second one because if you look at a lot of videos for a lot of different carburetors

Especially simple ones they all tell you the standard setting is the second setting but i found an old guy who was doing lots of video a lot lots our video on the importance of checking what your spark plugs are doing and this can be weather condition so if you’re riding in winter or summer you i would suggest you really look at what setting you’ve got on your

Pin so basically you pop this little clip off and you move it up or down one of the sections and pretty much that’s what i’m gonna do there’s a lot of people that have got a lot of things wrong in what they call bogging out and i reckon that this is going to sort it out because we’ve been riding in different temperatures so obviously now the temperature’s rising

In the year i need to put it up which will restrict the fuel and air flow coming through the carb rat because at the moment we’re getting far too much and you can tell that by holding your hand over the end of the carburetor where the filter is which is can’t see my finger over the end of here so basically what we’re doing is when we throttle the bikes dying so

It’s bugging out but when you restrict the air flow going into your carburetor okay the bike will continue to reven not bog and that is caused by the setting on that needle hopefully because everything else has been how to lock out all the timing took the to the carburetor of power flushed it out flushed all the parts out inside with some car cleaner so that’s

All good and this only happens just so you know when the bike is at normal operating temperature so it’s been running five ten minutes you’ve got to play around and maybe a little bit longer and then all of a sudden you’ll start to see the bike dies okay so pretty much what we’re gonna do is we’re gonna go ahead and change the setting on the needle go for a ride

Clell us and i’ll report back but pretty much if you want to know any more and this happens on all sorts carburetors not just these bikes loads and loads and just typing carb needle settings or spark plugs and basically you’ll find all the information you need but i thought i’d do a little video and tell you what i’m gonna do with a dirt bike just to get it going okay see you later

Transcribed from video
125cc dirt bike carb tuning By G B