This actually happened to me this weekend.
Its been at least 4 months since I rode my GG. Its been to damn hot here but this past weekend, there was a fun run down by Perry Mtn, not at PMC but close by. A place that had not been ridden since the ISDT 2 day qualifier back in the 70s! I had to go. I got there, unloaded my bike, removed the "butt plug" from the silencer and there was friggin' MOLD on the butt plug!
The trails were perfect! Perfect traction, no dust, just a little bit of mud. Had a great time! Ready to ride again. Oh and my bike started on the second kick after sitting for all that time.