Tires Persisting

My bike tires whir,
Moving along the dirt.
They grip the rocks and roots,
Saying their hellos and goodbyes,
Pushing me forward.
The grass and mud fights the force,
But the bike persists. 
It holds its own,
Fighting, 
And continuing to go forward.
They do their job,
Rushing me along the trails,
Without complaint.
The sticks admit defeat,
Cracking and crunching,
Realizing the bike is stronger.
My bike tires whir,
Inspiring me to persist.