thm-clavicula-crank-and-bottom-bracketIf you are like me, you sometimes fantasize about exotic, high-end products. I long for a Ferrari F12 Berlinetta or an Aston Martin Vanquish, neither of which I could ever afford.  I drool over articles about high-end audio components, imagining how I could possibly fit a pair of Magico Q5 in my living room. Like the cars, I’ll never have the speakers either.  In the cycling world, I think about things like a set of Lightweight Gipfelsturm or Reynolds RZR wheels. But one great thing about the bike world is that I may be able to actually get some of my dream products!  The THM Clavicula crankset is another piece of very functional cycling industrial art and one that is very worth drooling over.

While not a household name, if you have been a long-time reader of our posts you may remember mention of the THM-Carbones Clavicula crankset we installed on a very lightweight Guru Photon several years ago.  We’ve installed these cranks on a few bikes since and most recently on a client’s Parlee Z-Zero adventure bike.

Just How Light is the THM Clavicula Crankset?

What is so special about the Clavicula SE carbon crankset?   This crank is giggle-inducing light.  Honestly, I broke into a broad grin when I picked up this crank, followed by an audible chuckle.  The compact crank (110 mm bolt circle) with 170mm crank arms, without chainrings, comes in at 295 grams, (10.4 ounces).  As recommended by THM-Carbones, we mated the crank with a set of PraxisWorks  50/34 cold-forged chainrings, some of the best after-market chainrings you can get.  The combination weighs 435 grams, or 15.4 ounces.   That is incredibly light for a component that must stand up to the stresses of a crank, and it is the lightest crankset that I am aware of, from any manufacturer.  By comparison, the Shimano Dura Ace 9000 crankset, with chainrings, far from being a boat anchor, weighs 698 grams and a Campagnolo Super Record crankset comes in at 678 grams.  That’s over half a pound of weight savings on a component that is rotational mass (more meaningful than non-rotational mass)!

THM Clavicula Crankset Rider Weight Limit

So, what is the compromise? A crank this light must be flexible, wimpy, not very stiff.  Au contraire.  This crank rivals the stiffness of many of the top cranksets on the market, and when looking at the stiffness to weight ratio it is unchallenged.  It feels that way when you ride it – almost instantaneous response.  What is the compromise?  Well, for a product this light, there is a very realistic maximum of 120 kg, or 264 pounds, for rider and bike.

THM Clavicula Crankset Bottom Bracket Options

The THM Clavicula crankset requires the use of THM’s proprietary bottom bracket, in the case of the Parlee the PF30 version.  The THM bottom bracket is also light, weighing in at 100 grams and it works in the same manner as the Enduro TorqTite design, where the two halves of the bottom bracket thread into each other, pinching the frame between them.  This is one of the better ways to design a press fit bottom bracket when it comes to alignment in the frame and minimizing the chances of friction creak. The bearing design on the THM bottom bracket are external, meaning that they are outside of the frame rather than being squeezed inside the frame. This brings the bearings out to the very ends of the crank axle, for increased support of the axle and increased axle stiffness.

The whole THM Clavicula crank and bottom bracket package with the PraxisWorks chainrings is built to the highest standards, as you might expect, and performs equally well.  The crank is stiff with no noticeable flex, and of course PraxisWorks chainrings work really well. The bottom bracket spins freely, and is very smooth. The crank and bottom bracket are available to fit any frame with a standard 68mm BSA  or Italian threaded shell, BB30, Pressfit30, Shimano Pressfit (BB86/92), BB386 EVO, and Cervelo BBright-Pressfit, so the design is very versatile and will thus fit in most frames.  THM-Carbones makes the Clavicula SE crankset in 130 and 110 BCD for standard and compact chainring configurations.

Other THM Bicycle Components

THM makes other carbon fiber components as well. These include four versions of the Scapula carbon fiber fork and the very impressive THM Fibula caliper brakes that we use when folks are looking for ultralight weight while still maintaining powerful braking performance. I am not engaging in hyperbole when I say that I have never felt a set of caliper brakes with the stiffness, feel and power as the Fibulas and they weigh about half of a set of Dura Ace. I fantasize about getting a set of the Fibula brakes!

If you are looking to make your bike as light as you can without compromising stiffness and performance in the process, the THM Clavicula SE crankset is a “must have” component.  The best products are rarely the least expensive and the Clavicula SE crankset is no exception as it lists for $1,190. With a set of Praxis Works chainrings, Shimano Dura Ace chainring bolts, and the mandatory THM bottom bracket, the total is a bit north of $1,500. However, putting it all in perspective, unlike the aforementioned cars and stereo equipment, the Clavicula SE is actually a dream component that can be within reasonable reach for most folks with a little judicious planning.  Tonight, lying in bed before I go to sleep, I will probably be doing some math in my head…

Contact us for more information on the THM Clavicular SE crankset or to order.

About Jim

After almost thirty years as an attorney, Jim became the service manager at Fit Werx in Vermont. He held this post for almost ten years. Having retired in 2019, Jim still likes riding, working on and writing about bikes and bike equipment.


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