Follow up: Now, I'm approaching 400 miles on the Checkpoint and I've become more certain about the Isospeed decoupler . . . I don't like it. It is incredibly comfortable on rough surfaces. It DOES soak up the bumps! But on all surfaces, it introduces a flexy boing-boing-boing sensation. On smooth surfaces, the boing-boing-boing continues with every pedal stroke. If you are prone to motion sickness, stay away from the isospeed. My training partners say they can see the flex with every stroke. On seated climbs, it leaves nothing to anchor against -- making each stroke markedly less efficient than it should be. 100 miles into the Checkpoint experience, I was unsure. 400 miles in, the Isospeed becomes more annoying with every mile.
The moral of the story . . . although it can be extremely difficult to do so, be sure to test ride the bike you buy before you buy it. Test it for a ride long enough to highlight the bike's potential annoyances. I didn't (in part, because no bike has presented this big an annoyance in my lifetime) and I'm stuck.
Others may like the Isospeed decoupler. I don't. If you've never ridden one very far, be sure to try before you buy!
Last edited by FlashBazbo; 11-06-18 at 02:29 PM.