Oh she gets dirty. Here's a pic after riding the ol' Milwaukee electric train railroad tunnels from Idaho to Montana. Just wash in warm water and tumble dry. No bleach.
But to be honest coming from a very experience motocross background I can't see doing much other than logging road etc on these. There are too many other bikes Id choose to hit trails and get crazy. I absolutely love the GSA simply because its an absolute road killing monster! Heck I just rode her from CA to WA last week during that big storm and we did 2 days of snow. It was epic! I had a 1 hr mtg at a job site and didn't want to fly.
This was the radar the day I departed WA to come home. 3 days 2200 miles. Up I5 to 97, back down 800 miles of OR and CA coastline. Then I washed her to give a nice post!