Don't have my topo in front of me, but probably hike up to Triangle Pass from Crested Butte and down to Conundrum Hot Springs. That may be about 9 miles....take a dip in the springs, then head down Conundrum Creek 9 miles to the road that heads into Aspen.
definitely common to hike West Maroon pass from maroon lake trailhead. then take the east maroon creek trail over to CB. ~10 miles to the road, then hitch into town.
Its been a long time but I have mtn biked over pearl pass & back take alook at maps then you can ride into townn & sidetrips very cool you cant ride thru wilderness though also check out marble quarry on the aspen side