My commute seems to be stabilizing at about 70 min each way, give or take. The 1st 4 miles are w/ my son who is turning 8 next week, on his 20" raleigh, that has been taking ~35 min, and then the rest is me going 8 miles more to the office. The 70 min includes puttering time at his camp, signing him in, yakking w/ the counselors, that sort of thing. I can shave 10 min off the gross time pulling him on the trail-a-bike; cuts the leg to camp in half, but then I spend some of the gain at a roadside strawberry stand.