Motorcycle Repair: 1978 yamaha 400 2 stroke, cause havoc, yamaha 400

Question
hi, my name is brandon and i have a question on my 1978 yamaha 400 2 stroke. I just got it 2 weeks ago and it will start and run and drive for about 3 minuts or so and it will die like it is out of gas. then a couple of minuts later it will start agian but just to die. i had made sure that the gas was turned on.
                        thanks brandon  

Answer
Brandon,
 Be sure the choke is closed after the initial start up.  If it still dies you may have to clean and adjust your carburator/s.  here's some basic info I've given others on the subject;

Disassemble, clean all jets and orifaces with solvent and COMPRESSED AIR ONLY, use NO wire or picks to clean holes/airways. Rebuild carbs with new gaskets and make sure your floats are set correctly. . Do not overlook the float level, be very sure you are not starving for fuel or allowing too much to enter (there is a hieght setting for these in the manual). Inspect the needle valve for smooth operaration and any wear and debris. 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