Review on Ibera PakRak Commuter Bicycle Carrier by Narendra Thapa

Works great on big posts, not great on 25.4mm posts but works. With a 25.4mm seatpost, it will move slightly if you bump into it, but until you bump into it, it stays in place. I was able to solve this problem by cutting an extra piece of rubber from the pipe and adding it to the rubber that came with the kit to make it more solid. Update: 8/28/16 It works great with the carbon seatpost. I have a Cannondale C2 carbon seatpost and had over 20lbs in my pocket and weigh 170lbs sitting in the seat and bouncing with no issues. I love it.