Gordon
XS650 Junkie
Ok, on setting the float level. The proper level is just to the top of the bowl. The carbs don't have to be on the engine, BUT they do have to be level. Do like GGGARY stated. Get a metric 90 zerk fitting, or commonly known as a grease fitting, with some clear fuel line. Run the line up the side of the carb and fill carb with fuel where the regular fuel line attach's. You can put the carb in a vice to hold it level while you check all this. As long as the float move's freely throughout it's whole range there should be no problem's. Do check that the needle AND seat are in good shape as was suggested earlier. This is not real hard stuff, but it does require extream cleanliness, and good part's.Now the mixture screw's wont really protrude into the carb body, but will close off that hole in the body. Put the mix screw's next to each other. Looking very carefully at the point's of them. Are they the same shape and length? The tip ain't broke off one?That happens alot, Esp. if they were forced into the bore (hole). Bottoming them out will also break off the tip, so when they bottom, it is done with a light touch. From the bottom, for a starting point, turn each one out 3 turn's.
Now, Balancing is just as straight forward. Remove the slide's and diaphrams. With the carbs bolted together, put back in the vise. What we want to achive here is that they open up evenly together. The left carb is the one you sync to. So all adjustment is going to be on the right side. Someone posted this very proceedure with pic's. See if you can find it. On the left carb, loosel the idle SPeed screw until it close's the throttle plate fully. Shine a light through that carb from the plate rearward. Should very little, if any, coming by the throttle plate. Do the same for the right carb. Any difference in the amount of light? If no proceed as follows. Turn the idle speed screw on the left carb 1 1/2 turns inafter it touch's the boss on the carb. Now check with the light again on both carbs. Is it the same? If no, you adjust tis by leaving the left carb as it is and using the right carb idle speed screw. You can also use feeler guage's, but developing a 'feel' for this takes time- experience. It will come to you after you run/ drive around the streets for a while. Once you start doing maintenence, adjusting valve's ect. you will know how.
Ok, this is just a very basic adjustment to get the engine running halfway decent. Set the engine idle speed only using the left catrb. DO NOT touch the right carbs idle screw anymore. Now, adjust the idle mixture either using the dead cylinder method or just by ear. It will take several tries at the same time. In other word's, during the smae setting period. I suggsta window fan on high in front of the engine while doing this to prevent overheating. For the mixture screw's, I use a small slotted screwdriver bit about 2" long. They are available at Home Depot or Lowe's.
Once you do this a couple time's, you wil become an expert on it. Good luck to you, and congratulation's on having the courage to tackle this. Like I said, once you have done it a coulpe time's, you will 'see' how simple it all really is.
On the zerk fitting, there is a check valve inside with a spring that will have to be removed. Use a small drill to drill from the side that treads into the carb. Throw the spring and ball away.
Now, Balancing is just as straight forward. Remove the slide's and diaphrams. With the carbs bolted together, put back in the vise. What we want to achive here is that they open up evenly together. The left carb is the one you sync to. So all adjustment is going to be on the right side. Someone posted this very proceedure with pic's. See if you can find it. On the left carb, loosel the idle SPeed screw until it close's the throttle plate fully. Shine a light through that carb from the plate rearward. Should very little, if any, coming by the throttle plate. Do the same for the right carb. Any difference in the amount of light? If no proceed as follows. Turn the idle speed screw on the left carb 1 1/2 turns inafter it touch's the boss on the carb. Now check with the light again on both carbs. Is it the same? If no, you adjust tis by leaving the left carb as it is and using the right carb idle speed screw. You can also use feeler guage's, but developing a 'feel' for this takes time- experience. It will come to you after you run/ drive around the streets for a while. Once you start doing maintenence, adjusting valve's ect. you will know how.
Ok, this is just a very basic adjustment to get the engine running halfway decent. Set the engine idle speed only using the left catrb. DO NOT touch the right carbs idle screw anymore. Now, adjust the idle mixture either using the dead cylinder method or just by ear. It will take several tries at the same time. In other word's, during the smae setting period. I suggsta window fan on high in front of the engine while doing this to prevent overheating. For the mixture screw's, I use a small slotted screwdriver bit about 2" long. They are available at Home Depot or Lowe's.
Once you do this a couple time's, you wil become an expert on it. Good luck to you, and congratulation's on having the courage to tackle this. Like I said, once you have done it a coulpe time's, you will 'see' how simple it all really is.
On the zerk fitting, there is a check valve inside with a spring that will have to be removed. Use a small drill to drill from the side that treads into the carb. Throw the spring and ball away.
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