BBinfinite’s second product, the Delrin derailleur pulley wheels with Ceramitech ceramic bearings, came out at the beginning of the month to complement their perfectly aligned bottom brackets and reduce friction at the rear of the bike. We just got our hands on a set for Shimano rear mechs to see if they spin as freely as advertised (hint: they do) and add anything to the ride…
The BBinfinite wheels for Shimano 10/11 speed weigh in at 25g for the pair. The stock Ultegra 11-speed wheels are a little lighter at 21g.
First impressions are very good. I gave them the same spin test that BBinfinite showed in their promo video and the results were the same. Based on comments on that post, I held the Shimano wheels as lightly as possible so as to not put any unnecessary pressure on them, but they still managed only a few revolutions. With the same spin force applied by my finger, the BBinfinites spun smoothly for 20 seconds or more. Truly impressive.
The pulleys have a top and bottom specific design, with slanted tooth profiles on the directional lower pulley and a directionless standard tooth profile on the upper.
On the bike, I’m still in need of a long ride to suss them out, but spinning the cranks in the stand and a short ride through the neighborhood suggest they do indeed have a noticeable impact on friction reduction. The drivetrain felt smooth and light. Enough to justify the $120 price tag? That depends. I’d upgrade to their BB first, and then keep the drivetrain clean and lightly lubed. But if you’re already doing all that, then taking a cue from the top pros and upgrading the derailleur pulleys is an easy way to cut hidden drag.
Now it’s time to put several hundred miles on them and see if they still spin as freely and how well the wheels wear…