Barcode: 735201959009



Sram Eagle users rejoice! Now you can enjoy the supreme shifting and performance of a Kolossos oversized rear derailleur with your Sram XX1 Eagle AXS rear derailleur. Our new Sram Eagle Kolossos works with all mechanical and AXS versions of XX1 Eagle, X01 Eagle and GX Eagle.

About our Kolossos Oversized Derailleur Cage

Kolossos is the Greek word for a statue, much larger than the original subject. Sounds appropriate for replacing your 12 and 14-tooth stock pulleys with a 18-tooth narrow-wide bottom and a 14-tooth top pulley, built on our stiffest Kolossos cage yet.

Kolossos cages are built for reduced friction with shifting accuracy and chain retention in mind; something near and dear to all XC, marathon and enduro riders.

Ground clearance is not a concern as overall length is within 2mm of your stock cage, but doesn't hang lower. And, your Kolossos ships with our road seals for best efficiency, but can be swapped to cross seals for wet riding environments.


This Kolossos only fits Sram mechanical and AXS versions of XX1 Eagle, X01 Eagle and GX Eagle rear derailleurs. Does not fit non-eagle (i.e. 11 speed) or T-Type eagle derailleurs. For Transmission type Eagle derailleurs look here

**Kolossos is a component upgrade for existing rear derailleur. Derailleur not included**

Level up with Kolossos
Customer reviews
Customer reviews
I’ve been using the Kolosos, and BB for an year now, they still perform as it they were brand new!!! Shifting improved and going downhill with other people is where you will really see the ceramic bearings do their thing!!!
— Tincholeyes
Customer reviews
The Kolossos is definitely my favorite upgrade on my Orbea Occam. It shifts a lot smoother and it looks RAD! I went with a black cage, gold pulleys, & oil slick bolts. It's really cool how you can customize it to your bike. Highly recommend!
— Jkrawczyk71
Customer reviews
The setup has worked so well for me, it’s almost shocking. The hike is a hardtail, and despite this, I’m able to run the derailleur with the clutch off for all my off-road riding, without chain drops. So I get extra drag reduction! I also have to powershift a lot on my local terrain, and it always works. The claimed stiffness is real. Love it!
— Msurch
Customer reviews
Much stiffer than my stock cage and looks way better!
— Dwgreen27

Experience a silky smooth drivetrain

No amount of chain lube or coating can eliminate your rear derailleur's inherent design limitations. The path a chain takes during each revolution requires passing through a chicane of derailleur cage pulleys diminishing your return on each pedal stroke. It's a drag on all geared bikes and why your stock rear derailleur will never perform as efficiently as one with an oversized derailleur cage.




Installation is easy, but does require disassembly of the stock cage.

The process takes roughly 20 minutes, including minor adjustments to the B-screw and limit screws to fine tune placement on the bike.

Frequently asked questions

How hard is it to install an Oversized Derailleur cage?

Installing an oversized derailleur cage is best left to expert level mechanics. Derailleur manufacturers do not support disassembly of the derailleur. For this reason online instructions will be limited.

The installation procedure is also different for each model. Some types are straight forward, with some types you need to disassemble the entire cage and use proprietary tools for the installation. With others you run the risk of having to rebuild the clutch if the parts pop out while you’re happily tooling away. Derailleur failures are typically expensive: the chances of breaking a wheel or a seat stay are probably not worth the risk.

Kogel recommends leaving the installation to a professional.

Will my existing chain work?

It depends on the model. Typically Kolossos for road derailleurs require a slightly longer chain than the stock cage.  If your derailleur was built for a 1x setup, typically the upper pulley is off set from the pivot point and we can design it in such a way that you can use the same chain length.

Will I notice a difference in performance?

Yes and No. Kolossos has been designed to shift just as accurate as your stock derailleur cage. You will notice reduced drive train friction. Upgrading to an oversized derailleur cage is one step in the eternal search to go faster with less energy.

Are Oversized Derailleur cages loud?

The only sound you will hear is from using aluminum wheels instead of plastic. Aluminum wheels are stiffer and more durable than their plastic counterparts at the expense of a faint rattle when the chain runs across the cogs. We like to call it the sound of speed.

What are the downsides to an oversized derailleur cage?
  • Some installation requires a new chain
  • Slight reduction of ground clearance on road bikes. Gravel and MTB Kolossos are the same length as the stock cage
  • Your friends will envy you