Motorcycle Repair: 1973 Honda, combustion chambers, rubber hoses

Question
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Well you're right, I am not at all familar with motorcycles. But i did take apart the float bowl jiggers. I think my problem is that no gas is entering the combustion chambers, i took apart the fixture that hooks up to the gas tank and regulates the flow of gas, because no matter what setting (RES, ON, OFF)it was on , no gas would flow out. I cleaned all the gummed up gas residue as best i could, also using a thin gauge wire to poke out some of the gunk, and am now soaking it in gas to try and dissolve whats left. Oh, after the wire treatment, one of the two nozzles was dripping gas, so it might be salvageble. The two rubber hoses connecting this fixture to the air/gas mixture chambers are clear and there was plenty of gas in the float bowls (lol). What im worried about is how this mixture enters the engine. Is there supposed to be a vacuum created in the engine? I ask this because i checked to see if the nozzles on the air mixture chambers were clogged by attaching a hose to each side and blowing throught it, i was met with a lot of resistance, so im wondering how the gas is supposed to enter these chambers simply by gravity? Are they actually clogged?, because the engine turns over and over, but never "catches". Thanks again. -Chris

Answer
Chris,
 If you are getting a good strong blue spark at the plug you may be dealing w/ a fuel delivery problem.  The carbs. on that model may be vaccum assist meaning the engine must be running to help draw fuel at a regulated rate down to the carbs.  Of course, make sure your petcock/tank fuel valve is clean and clear and it's a good idea to use an inline fuel filter to each of the carbs. in a bike of this age.  If any rust or other debris gets into the carb. you will have problems.  If you are still not getting enough fuel to sustain running you are going to need to look at the carbs. again.  In a vaccuum assist system you should be left between starts w/ a full float bowl, enough to start.  If you have no start you are either suffering from a low float bowl level or improper atomization of the fuel.  Here are some basic procedures to follow I've given others on this matter:
Disassemble, clean all jets and orifaces with solvent and COMPRESSED AIR ONLY, use NO wire or picks to clean holes/airways. (I'm unclear if you used wire to clean the jets of the carb. or just the petcock, NO picking in the carbs! This can damage the precise action that takes place to provide the proper fuel delivery.) Rebuild carbs with new gaskets and make sure your floats are set correctly. Also be sure your floats don't have a leak that is causing them to sit at the bottom, I've seen this w/ older models that use sottered copper floats. Do not overlook the float level, be very sure you are not starving for fuel.  Check that the needle valve is moving smoothly and not worn to the point it is letting fuel by when seated.  In relation make sure fuel flow is unobstructed and use a good in-line fuel filter from the tank to the carb. Even tiny particles in the fuel can get logged in critical areas and cause havoc.

Hope this helps,
Mike