Found: FSA Almost-Standard Chainrings for Compact Cranksets

FSA standard gearing chainrings for 110BCD compact cranksetsWhen 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.

Comments

Poo Joe - 12/28/11 - 6:36pm

this is old. like 2k9 old, maybe older. been on cannondales forever. new-for-2012 is specialized speccing “mid-compact” 52-36 on a lot of sram and sworks cranks.
*snore*

Laadeeda - 12/28/11 - 9:52pm

Specialized did it for 2011 as well. The 52-36 is a broader range than 52-38, I don’t see why FSA wouldn’t offer that combo, although you could just buy a 36. Speaking from experience, front shifting on the 52-36 see’s no loss of crispness when set up correctly compared to a standard set-up. I’ve been running the 52-36 for the past year and absolutely love it. Going to school in the mountains, but calling the coastal plain of North Carolina home, it’s nice to have that much of a range.

kcr - 12/28/11 - 10:07pm

uh SRAM and and FSA have done this for like forever… at least two years. I’ve SRAM red rings on my bike in this size for over two years.

Bike Candy - 12/29/11 - 12:00am

Agree with the other postings. I’ve been running 52/36 FSA rings on my bike since 2006. I’m not sure what the “news” is here.

Johnny Pannini - 12/29/11 - 7:47am

Not all of your readers/fans including myself were aware of the existence of mid-compact rings so thank you for posting this short but informative piece.

Steve - 12/29/11 - 9:59am

Seems like the rings are stiffer than other offerings in the same tooth counts. That is new.

James S - 12/29/11 - 12:51pm

Man, you roadies are serious princesses if you can really detect the difference between 52/38 and 53/39. Wow, I can’t even imagine the awesome sensitivity that allows you to feel that a 53 is just too flexy and a 52 is just right. But then, I can’t really feel any difference between a square taper crank and anything else. I guess I am just an insensitive heathen.

bart - 12/29/11 - 1:42pm

what isn’t news is people making unproductive comments. go ride your bike, I am sure this has enlightened someone out there and they are now stoked because they can get some go fast rings on their compact crank that don’t suck

Steven - 02/08/12 - 8:29pm

I have been running SRAM Red 52/34 on a compact for the last year with a K-Edge chain watcher with great results. Am currently setting up a new bike with the same ratio on a compact K-Force crank.

Phil - 03/08/13 - 12:05pm

The reason the racers are looking for a 52-36 or a 52-38, or whatever “special” combo is all about being able to turn the pedals over to go as fast as they want for a particular race circumstance, have the gear range they need, and have the shifting response they expect, and not sacrifice too much, or preferably anything in any of these areas. Being able to sit and spin on a long climb is a common desire. Spinning also allows you to be able to respond immediately in climbs to changes in speed, like responding to an attack. In spinning, the power output comes principally from the rotational speed, as opposed to the tangential force applied to the pedals. Going over 28 teeth on the rear requires a long cage RD, and also neutral wheel support is not going to have your “special” cassette gear selection on one of their wheels if you flat. A smaller little ring gives you lower gearing and allows you to be normal on everything else. The 52 as opposed to the 53 doesn’t sacrifice much on the top end (only the really powerful pros will push a 53-11, most only spin it) and by reducing the tooth gap from small to big, it improves the up shift on the front.

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