Motorcycle Repair: 82 Honda Magna VF750C, battery tender jr, honda magna

Question
Mr. Johnston,
I bought my honda last year, and it ran fine - it started everytime. Last year I replaced the battery (it's connected to a battery tender jr), and changed all the fluids. It's been in my garage all winter (I live in Nebraska), and put sta-bil in the tank. It won't stay running - it will start sometimes, and run briefly - then quit. I changed the spark plugs today and it still won't start. It sounds like it's turning over - just won't start.

Answer
As you know it takes three things to make an engine run...compression, spark and fuel.  You didn't mention if it would continue to run if you left the choke on.  My response is assuming it won't continue to run with the choke on.

I'd vote for the fuel pump relay.  There's a small rectangular relay that controls the fuel pump.  It gets a signal from the ignition module when the engine is running to turn the fuel pump on.  Normally it will turn on the pump for about 3-5 second when the key is first turned on and shuts off.

My daughters VF700 had exactly the same problem and that's what it was.

Let me know if that wasn't it and we'll try something else.  

Good luck