Wolf Tooth Components GC40/42t
The Giant Cog, You asked for it, WTC made it -- the Wolf Tooth GC is now available in a slightly smaller size! Most of the low gearing from its big brother with improved shifting in the smaller cassette cogs.
We have chosen to make separate cogs for Shimano and SRAM for two reasons: 1) we design each one for the best possible shifting performance instead of a compromise on both and 2) installation is simplified because no extra spacers are needed.
Use of this cassette sprocket requires removal of the 17T or 15T cog & spacer from your cassette.
Note on “B-screw”: WTC has found that a longer screw is almost never needed with SRAM derailleurs and only needed for about 50% of Shimano derailleurs. WTC has added it as a separate item in their accessories category. If you think you might need the longer screw, order one separately (CBO part number 100140788).
You may need a longer chain than what is presently on your bike. Make sure that when shifted to the 40T cog, there is still some amount of forward travel possible with the rear derailleur cage. This is especially important on bikes with rear suspension. WTC has tested with Shimano, KMC & SRAM chains – all function well.
**Note: the GC is not compatible with 2011 or older SRAM rear derailleurs due to the location of the upper jockey wheel. It is difficult or impossible to get satisfactory shifting with the 2011 or older SRAM rear derailleurs so WTC does not recommend using the GC if you have one of these.
The Wolf Tooth Components GC cassette cog is available in two versions: one for Shimano cassettes and one for SRAM cassettes. This Shimano version is compatible with the following models:
- Shimano: XT 11-36t (CS-M771)
- XTR 11-36t (CS-M980)
- SLX HG81 11-36t - Modification required (must drill out rivets holding the 17t to the larger cogs)
- SRAM: PG 1030, 1050, and 1070 - 11-36 and 12-36
- X0 11-36t(XG - 1080) - Remove the 14t rather than the 17t
- Sunrace: 11-36t cassette - note that it was not designed for this cassette but the Shimano GC does work ok