In reply to gammarus:
I agree with Rick.
Walked it last year and it's a pretty rough path though good for walking. Our moving time was 6 hours 10 minutes and we are definitely not athletes. Most people could easily beat this if they wanted to.
It's only 2 miles until you start going up, 5 miles is where you would ditch the bike (1 hr 45 for us walking) and it would be just as hard going back as going out.
Unless your name is Danny MacAskill
Save it for a clear day, the view into Loch Coruisk with the whole ridge in panarama is out of this world.