Motorcycle Repair: Wolverine wont run right, long periods, tactical error

Question
Chris, I had my good running 2000 Yamaha Wolverine in storage about a year, took it out and it seems to idle just fine but when I throttle it up it "pops" and stutters, tried the choke in all positions and made sure there was clear air to it, put a new plug in it, no difference. Is it ignition or carburation? Thanks!

Answer
Hi Dave.

 My guess is that you left fuel in the tank and carb.  Major tactical error.  However, it is also a common error from most riders who store their machine for long periods.

 When you leave fuel in the fuel system, it will, over time, leave a residue that we call "varnish".  This residue gets into everything and messes with the fuel flow.

 Here's what you need to do to fix it; Clean the carbs, completely and thoroughly.  Drain the fuel and reseal the tank.  Replace the fuel line.

 Next time you store the machine for long periods, remove the fuel from the tank and run the engine til the fuel in the carbs is run out.

Good luck and ride safe.
FALCON