Wolf Tooth Components GC 49T Cog and WolfCage Kit for Shimano 11-speed

by Brian Mullin on November 17, 2016


The Wolf Tooth GC49 cassette extender cog allows you to modify your existing Shimano 11-speed 11-42T cassette to create an ultra-wide range 11-49T cassette system, which is close to mimicking the gearing offered by the uber expensive SRAM Eagle 12-speed 10-50T drivetrain. It was optimized and works with various standard freehub body compatible 11-speed 11-42T cassettes, including Shimano XT, XTR and SLX, SRAM NX and SunRace. All Shimano derailleurs require their WolfCage derailleur cage kit to function with the GC49 cog, while SRAM 11-speed derailleurs will work in a stock form with the 11-49T cassette stack with only a few minor tuning alterations. The tested GC49 and WolfCage kit retails for $124.95.

For further information refer to www.wolftoothcomponents.com

Ignoring hub bodies costs, a cassette/derailleur/shifter/chain for Eagle is $800, a XT 11 is $293, add a Wolf Tooth 49T/WolfCage for XT for 11-49T gearing is $418. SRAM has not offered me an Eagle to test/review, and doubtful they will, so I can’t comment on its performance, but I assume it would be excellent.


GC49 Cog

The GC49 kit retails for $89.95 and provides a 49-tooth extended range cog and an 18T replacement cog, and comes in a slew of colors in either a Shimano or SRAM/SunRace version. The Wolf Tooth 49T cog is made from 7075-T6 aluminum and weighs 110 grams and fits at the end of the cassettes and you remove the current cassettes inner 17T and 19T cogs and replace them with the kits included steel 18T cog to create an 11-speed 11-49T system. Wolf Tooth made the decision to use a 49T cog instead of 50T because it allowed them to nearly double the number of shift gates from 4 on a 50t to 7 on a 49t for faster shifting, and the 2% difference between them isn’t significant enough to lose the improved shifting characteristics.


WolfCage Derailleur Cage

The WolfCage is a modified derailleur cage with an eccentric pulley that replaces the stock 11-speed Shimano inner cage and its upper jockey wheel, and the system improves chain wrap and derailleur capacity for the extended 11-49T range setup. It comes in a variety of colors in XT and XTR models in either medium cage GS or long cage SGS versions and retails for $39.95 and is also available as part of the ’49T GC Cog and WolfCage Kit for Shimano 11-speed’ that I tested for $124.95. The WolfCage is made from 6061-T6 aluminum and is only compatible with mechanical (no Di2) Shimano 11-speed rear derailleurs, including SLX, XT, and XTR.


GC49 Cassette Installation

Usually, I would have removed the old cassette off the rear hub to perform the installation, but I was starting with a brand new XT 11-42T cassette, so setup was a tad easier. I removed the 17T and 19T cogs and the accompanying spacers from the stack, and replaced them with the Wolf Tooth 18T cog and one of the original spacers. I then slid on the Wolf Tooth 49T cog onto the freehub body, and then the rest of the newly created XT stack, and cranked down the lockring to specs. I liked that the Wolf Tooth cog had a small white dot pointing at the thin spline, so it made it easy to line everything up on the freehub body. To help prevent the 49T cog from digging into the soft material of most freehub bodies, it has wide tabs by the spline for a better load distribution.

Gearing Comparison:

  • Stock:                 11-13-15-17-19-21-24-28-32-37-42
  • WT GC49 kit:   11-13-15-18-21-24-28-32-37-42-49

By swapping out the old stock 17T and 19T cogs and their spacers with the 18T and adding on the Wolf Tooth 49T, it increased the rebuilt cassettes weight by approximately 89 grams.

Measured Weight:

  • WT GC49T extended range alloy cog – 110 grams
  • WT 18T replacement steel cog – 24 grams
  • Stock spacer – 2 grams
  • Stock 17T & 19T cogs/spacers – 47 grams
  • Total weight gains w/ WT GC49T kit –  89 grams


WolfCage Installation

The WolfCage installation only took me a couple of minutes, and it was even made easier in my case since I was starting with a new Shimano XT SGS long cage derailleur. Using a 3mm hex key remove the bottom derailleur pulley screw from the outside of the derailleur and set aside the jockey wheel and screw, paying attention to the directional orientation of the wheel. Then remove the top derailleur pulley screw from the inside and save the screw. Mesh the eccentric tophat jockey wheel onto the top WolfCage dished pulley location and then insert the original screw into the hole until everything lines up and lightly tighten down. Replace the original lower jockey wheel and it’s screw, making sure it is rotating in the proper direction and tighten down. Once everything looks respectable, torque the upper and lower bolts to 3.5 Nm.


Derailleur Tuning

I had to set the high and low limit screws on my new XT SGS derailleur to match up with the 11-49T cassette stack, and while pushing over the parallelogram to do the Low setting I had to crank out the B-tension screw a couple of turns to get the pulley past the larger upper cogs. Once I got the limit screws adjusted properly, I cut the shifter housing and cable to length, and pulled the slack out of the housing, feed the cable into the clamp and cranked it down to spec. I added a new full length 114 link SRAM PC 1170 chain, which seemed about perfect for my 49T rear cog and elliptical 30T front chainring combination. The shifting was just fine until I got up by the 42T cog and in particular, the 49T, and it required maybe 3-4 full turns of the B-tension screw to get the upper pulley not to rattle against the cogs and for the chain to roll up onto the 49T. After setting the B-tension correctly, I didn’t have to do any fine tuning of the cable at shifter barrel adjuster.



So how does it ride and shift?

It shifted surprisingly well, and the roll up from the 42T to 49T was quick and smooth, without any hesitation, even when done under load. It seemed a touch clunkier dropping back down to the 42T on occasion, though it always provided proper shifting functionality.  After riding for a while, I didn’t notice the shifting differences and was able to move through the gears without any issues. One of the odd sensations was getting the brain used to having the gearing all moved down one step. Meaning when I initially used the second lowest gear for cranking through technical maneuvers, that gear was now down in the third position. I didn’t notice the missing gears in the high range, since now I had an 18T instead of the 17T and 19T pair, and it shifted flawlessly through all the smaller cogs. I was thoroughly surprised how effortlessly and smoothly the chain rolled up onto the massive 49T cog, and I think their use of seven shift ramps or gates on the cog greatly facilitated the shifting along with the assistance of the WolfCage’s pulley realignment.

I enjoyed having the new 49T for my lowest gear, especially on my 27.5+ bikes, and it offered excellent slow speed spinning on steep terrain. Using the 49T cog felt incredible on long, arduous climbs, and I was able to spin at a sweet slow cadence, saving the legs from the usual energy sucking and lung busting predicaments.


I have taken it out for multiple days of riding, and it has shifted flawlessly, in fact; I would be hard-pressed to realize that I had this gearing installed on the bike. I cranked things under heavy loads on some pretty steep terrain, in both loose and smooth conditions, and the shifting and power transfer worked fine. With the big fat wheels on my Ibis Mojo HD3 27.5+, I appreciated having the 49T combined with an elliptical 30T chainring, which provided a very pleasant and useful gear ratio.


Bottom Line

The Wolf Tooth GC 49T and WolfCage kit offered an excellent extended range 11-49T 11-speed gearing, and it’s especially functional for long steep climbs, and 29ers and 27.5+ bikes. The combination of the Shimano XT derailleur and WolfCage inner derailleur cage system worked flawlessly with the large 49T cog. It only works with Shimano SLX/XT/XTR and SRAM NX/SunRace 11-speed 11-42T cassettes, but the 49T cog melds with them like it’s part of their standard gearing. It closely replicates the stock cassettes gearing in the smaller cogs, and it didn’t seem to be problematic replacing the 17T/19T pair with the 18T cog. You can purchase the GC 49T for $89.95, the WolfCage for $39.95 or the entire GC 49T/WolfCage kit for $124.95, and everything was simple to install and only added 89 grams to the stock cassettes weight.

It offered great shifting characteristics throughout the entire gear range, and the 42 to 49 jump was smooth and quick, even under load, while the drop back down occasionally made a clunking noise it never caused any shifting issues. The entire kit only added 89 grams to the drivetrain system, and it was almost invisible in its function and shifting, and outside of the lower gearing, I would be hard pressed to know that the large dinner plate 49T cog was installed on the drivetrain.


  • Wide range 1×11 11-49T gearing
  • Low 49T gearing is ideal on long steep climbs – especially with a 29er and 27.5+ bikes
  • Great shifting characteristics
  • Simple installation
  • WolfCage – flawless 49T shifting


  • Only works with 11-speed 11-42T cassettes that are standard freehub compatible
  • 89-gram weight increase over stock XT 11-42T
  • No 10T for SRAM like lower gearing
  • Shimano drvetrain requires WolfCage kit

{ 6 comments… read them below or add one }

Leonel November 19, 2016 at 4:33 pm

Dear all,

I have a SRAM 10t with X01 dearailleur and X9 shift, is it possible to perform this upgrade?


Brian Mullin November 28, 2016 at 4:40 pm

It will only work with 11-speed non-XD driver body (only SRAM PG-1130), meaning a normal freehub body.


Paul July 9, 2017 at 11:24 pm

I’m running XX1 drive train 11-42, is this compatible?


Brian Mullin July 12, 2017 at 10:54 pm

No, it only works with non-XD Driver freehubs. The closest you can get is their GCX 46T Cog for SRAM XX1/X01 cassette.


tom chong August 9, 2017 at 9:33 am

i m using xx1 10-42 . u have 46t?


Brian Mullin August 16, 2017 at 12:27 am

You could go with one of their ‘GCX 46T Cog for SRAM XX1/X01 cassette’ instead since the 49T system doesn’t work with a SRAM XD driver freehub. The 46T replaces the stock 42T, for a 10-46 range.


Leave a Comment

Previous post:

Next post: