Found: FSA Almost-Standard Chainrings for Compact Cranksets
When buying a bike or upgrading to a high end crankset, many of us are stuck with the decision between standard and compact. And it can be a tough decision, locking you into smaller or bigger gears that may be right for one situation but not others.
FSA feels your pain..
First, a quick primer. Standard cranksets use a 130 BCD (bolt circle diameter) to mount the chainrings. Compact uses a 110 BCD. The smaller BCD allows for smaller rings on the compact, and the larger Standard BCD puts the bolts further out to keep the rings stiff under power and shifting. For most brands, a Standard crankset comes stock with a 53/39 ring combo and Compact comes with 50/34 (which is what’s actually shown here).
Assuming you found some with a 110 BCD, you could put Standard tooth count rings on a Compact, but FSA’s Matt VanEnkevort says the rings would start to flex under power, particularly the big ring, and performance and shifting would suffer. Their solution? A 52/38 chainring combo for 110 BCD Compact cranksets, which he says gets it close enough to Standard for most riders without degrading shifting performance.
As someone who routinely wishes for just a slightly easier gear than what a Standard 53/39 crankset allows (even with one of the larger cassette ranges installed) but spins out of a Compact too quickly, this is pretty appealing. In fact, we have a set in the office that’ll start seeing some miles soon for a review.
They’re available as a stock option their Vision TriMax Pro in both MegaExo and BB30. They’re also available aftermarket in both Pro and Super trim levels. Both are machined from 4mm AL7075/T6. The Pro rings have machined tooth profiles. The Super rings get that plus a larger surface area with extensive machining on the back and front sides to reduce weight while maintaining stiffness. The Super rings are what’s found on their top of the line K-Force cranksets.
Prices for the Super rings are $79.99 (52T) and $54.99 (38T). Pro rings are $54.99 and $38.99.