Originally Posted by
Kotts
I was wondering whether others have experienced the effect I have.
Some days I "feel fast" (and am faster) on my commute, and other days, under almost the same conditions, I feel like a turtle dragging the Titanic's anchor.
For example, yesterday, I easily averaged about 16.5 MPH on my commute. Riding in this morning, I was having a hard time averaging 14.6. Headwinds both days.

I'd be suprised if anyone didn't.
I've had days where I was so slow i hopped off the bike several times to see if my wheels were rubbing on something or if I was way low on air. They weren't.