Biking - a Poetic Quip on a Cycling Trip

My friend and I were going biking,
Until my shorts, they started hiking.
They went north, and I went south;
In short, we had a falling out.
We had to stop and readjust,
I mounted up again, nonplussed.

Then, bent in two, I grabbed the bars
And dodged three more oncoming cars.
My spine in spasms, I persisted,
Until my knees and calves resisted.
"Isn't cycling grand?" I cried.
"Let's go tomorrow," Sam replied.