I usually bike to work in shorts and then change but there are times I don't want to be bothered...
I have found that even using a strap, I can get oil on my pant leg... I decided to make myself a gaiter
out of a pair of old sweat pants (the kind that have the elastic at the bottom of the leg. I cut the leg to
the size I wanted and I put that over my cuff and secure it with a leg strap...

its especially useful for when it gets colder...