Technical FAQ: Putting a Shimano 105 compact crank on a Dura-Ace bike

Can I put a 105 compact crank on my Dura-Ace bike?

Dear Lennard,

I am planning to travel to Europe to do some traveling, cycling, and catch a bit of the tour. I am big guy, and struggle going uphill. At home I ride a Devinci Leo with full Dura-Ace 7800, 53×39, with a 12-27, which is OK for Northern Ontario.

Is there a way to economically put a 105 compact crankset on my bike to help in the hills of Europe? Or should I bring my winter bike with a triple and 105 / Sora mix? I would really prefer to ride my good bike as it is lighter, more comfortable and more reliable, but I really am not interested in walking up the hills. No matter what bike setup I choose, I know the high passes are not for me.

Dear Guy,

You can just slap a 105 compact crank right into your existing bottom bracket; there is no reason to change anything other than the height and cable tension of the front derailleur.