I did Ben Avon, Beinn a Bhuird, Beinn a Chaorainn and Beinn Bhreac as a bike/hike. I left the car at Linn of Dee, cycled to Invercauld bridge where I dumped the bike. The walk was 27 miles and took 10 hours 40 mins, can't remember how long the cycle took, but probably about half an hour.