Motorcycle Repair: 82 Honda V45 Magna, honda v45 magna, honda vf750c

Question
My buddy just got a the bike and it will not run with the choke off or will not run past 2K with the choke on.  Starts right up every time we try.  We changed the oil and oil filter, put in new fuel filter and spark plugs and choke oil.  Air filter will be in next week.  Why will it not run?

Answer
Kent, assuming that all 4 cylinders have spark and good compression, then the carb rack will have to come off for a good cleaning. Idle jets are tiny and easily plugged up after 28 years. The spark units can fail killing off one set of plugs.

With choke on, the mixture is too rich for higher revs and/or the main jets/emulsion tubes are blocked off with old fuel deposits. creating over-rich conditions. The carb diaphragms all need to be checked for pinholes/tears.

Buy some carb gasket kits and lots of carb cleaner and pull them off and apart. You might want to get a good OEM book to help you along with this process.

http://www.cmsnl.com/honda-vf750c-v45-magna-1982-us_model761/partslist/
for illustration purposes and current part numbers.

Do the basics first... adjust valves, take compression readings, look for air leaks, clean fuel system from gas cap to float bowls.

Bill Silver