First Look – FSA Comet Fatbike Crank


Puck started having shifting issues on a recent Full Moon Beach Ride owing to the worn out status of the drivetrain on his Tatanka. One ting we don’t need around FB.c World Headquarters is an ornery Puck because his bike isn’t working so we set about remedying the situation. After getting a new SRAM Chain and SRAM 11-34 rear cassette we were on the hunt for a suitable new crank to get a fresh set of teeth on the front. Low and behold there it was sitting right on the product photo table here at FB.c WHQ; an FSA Comet Fat-bike Cranks and FSA 100mm MegaExo bottom Bracket that FSA had recently sent us to get a look at and to install on a fat-bike for some real-world testing. So, on to the Thrash Master General’s bike went the Comet.

For a couple of years FSA has had some cranks that are compatible with 100mm BBs by using a 100mm ISIS setup with the crank arms separate from the BB but the new Comet is an integrated design made specifically for fat-bikes with the spindle attached to the drive-side crank arm and the non-drive crank arm attaching to a splined spindle on left side of the bike using FSAs “No Pinch Bolt Design”. At well under 1000g for the complete crankset and BB, the Comet is significantly lighter than previous ISIS cranks.


Installation was pretty much a breeze. We used the 2.5mm E-type mount and another 2.5mm BB spacer on the external cups and that put us pretty much right where we needed to be for the width. Torque it down to specs and the crank spun freely with no play found.


Initial rides have shown that the crank does what it is supposed to do. Spins ‘round when you mash on the pedals, shifts well with the 2x 36/22 chainrings giving plenty of fat-bike gear range and, in general gets out of the way and lets you enjoy the ride.

FSA Comet 100mm Fatbike Crank Details

  • Fat / snow bike crankset compatible with the 100mm BB standard
  • Forged alloy crankarms
  • All 2X Comet chainrings available (Our test version has stamped alloy 36/22 chainrings)
  • Cr-Mo steel chainring bolts
  • NBD (No Pinch Bolt Design)
  • Compatible 10 speed System MTB
  • Q-factor: 209mm
  • 170 / 175mm crank arm lengths (175mm on the test set)
  • Counter sunk MegaExo spindle
  • 878g (175mm)

FSA MegaExo 100mm External Bottom Bracket

  • 24mm Spindle Diameter
  • Aluminum Inner Spindle cover
  • 119g

The above 2 parts are sold together and retail for $165.00

Here comes the rest of the story…


So, to install the new crank, Puck first had to remove his old crank that was a Hussefelt fat-bike crank from a couple years back when it was the only in-stock fat-bike crank around. It is a super strong, bomber crank but we knew that it was a bit on the portly side. Weighing it on the same scale as we weighed the Comet it came in at 1420g. Yes it is very strong and the weight shows it. The new FSA Comet is basically a full pound lighter than the Hussefelt/GigaPipe BB combo!

Here is a reminder to check out your BB Shell once in a while, especially when you ride your bike year 'round, in and out of lakes!

Here is a reminder to check out your BB Shell once in a while, especially when you ride your bike year ’round, in and out of lakes!

Saving a pound on a fat-bike is a great thing! I’d expect to see this crank specced on a lot of mid-level complete fat-bikes for the 2015 model year and, if you are still running an older crank or have a heavy OE crank, at an MSRP of $165.00, the Comet is a great way to get that new shift feel back while shaving some weight off your rig. Dig!

FSA Comet and BB = 990g

FSA Comet and BB = 990g


Hussefelt Crank and BB = 1420g

FSA sent us a selection of Afterburner cockpit components as well and we will have a look at those in a few days!

Disclaimer: FSA provided the Comet fat-bike crank for review. However, regardless of how we get test products, for review from a manufacturer, bought with our own $$$ or borrowed from friends, our reviews will always give our honest opinion and real-world experience!

2 Responses to First Look – FSA Comet Fatbike Crank

  1. Puck February 25, 2014 at 11:26 am #

    I really like the way these cranks rode, first ride was pretty hilly and and fast, didn’t notice any flex at all!!
    I was also able to take out the two sets of pedal spacers needed on the old cranks so my Wolvehammers wouldn’t hit the crank arm!

  2. Thepugmasher August 8, 2014 at 4:27 am #

    Do you know what the chainline is for this crankset, I need a 72mm for my pugsley necromancer.

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