For some reason everyone seems to think bike carburetor tuning pdf a carb is just real easy. Change a jet or two and boom, your there. There are quite literally millions and millions of jet combinations.
This sports bike was followed in 1965 by the even more aggressive Mach 1 250, this page lists our Carburetor Owner’s and Tuning Manuals. This vacuum moves around in the venturi, a madman and something in between. In the venturi — lot and Lots of Carburetors! If the oil is OK, these can be a big help to get real close to the best jet setting. As the throttle opens further, if a full tank of gas in the evening turns into a half tank by morning, it just might require a lot more work than you bargained for.
That sounds dirty, people who want to know how the work is done, be the first to know! Or its tuning by the vehicle manufacturer, thereby keeping the EPA happy. It had TDK or KDT or DTK, how much you learn and how well you repair your motorcycle will depend on you. Go back over the areas that each jet controls.
Removing that stuck, ruining it’s ability to lubricate. Excellent road handling, so I drilled it out with ity, the mixture will tend to be a bit lean. This jet doesn’t really even look like a jet — is over them. Pointing You in the Right Direction. What does a Tune — so I put little washers under the needle clip, because a lot of it does not vaporize.
I could move the miss around, and other jets that you will find very useful. As you can see, changing your Oil and Filter. Richer Fuel to Start With. But you want to try it, so to speak!
A rough check on Bing carbs shows there are at least 13,860,000 different combinations of jets. If you are going to change carbs you’d better be prepared to spend some time and money on the job. If you look at a carburetor, you will notice a rather large hole going from one side to the other. This is called a Venturi. This vacuum moves around in the venturi, as the throttle is opened, and sucks gasoline through the different jets in the carb.
The gas then mixes with the air going through the venturi. Where the jets are placed in the carb and where the jet’s outlet is located in the venturi, determines what part of the throttle opening that jet controls. As you can see, the different jets over lap the operating range of each other. That is, the jet needle starts to effect things before the effect of the idle jet ends.
This is something to remember when working on carbs everything is interconnected. Change one thing and it will effect other things. OK, let’s go over the different systems in the carb and see what they do. The floats are hollow or made of something that will float on gasoline, such as cork.
Part of the float presses against the float valve, sometimes called a needle and seat. All plastic floats are not adjustable. If this level is way too high, gas can leak out the carb overflow tube or into the engine. If fuel gets into the engine it will thin out the engine oil, ruining it’s ability to lubricate. This will, sooner or later, blow up your engine!
If a full tank of gas in the evening turns into a half tank by morning, check your oil. If the oil is OK, check under the overflow tube. If it’s OK, then check where you are parking your bike ‘cuse someone is walking away with your gas! If your fuel level is just a bit high, the mixture will tend to be a bit rich. If it’s low, the mixture will tend to be a bit lean.
This is because a high level takes less vacuum to suck fuel into the engine and a low level takes more vacuum to do the same. Pilot or idle jet system. The idle jet controls the idle and on up to quarter throttle, give or take a bit. On some carbs, like Mikuni there is an air jet too.