With Shimano 11 speed mountain bike cassettes turning up more in the real world via the workhorse XT 8000 group, and with an SLX 11 version on the way this July, Wolf Tooth decided that it was high time to bring their extended cassette offerings up to 11 speed as well. Optimized for the new Shimano 11-40 cassettes (but also compatible with 11-42) the extra 45T cog of the GC45 will boost your new Shimano 1x to climb some serious steeps. It can even be combined with a double setup, paired with a long cage rear derailleur and proper chain length, for the huge gear ranges…
Just like Wolf Tooth’s 10 speed kits, the new GC45 was designed to provide quality, predictable shifting and durability in the conversion. To get that performance out of such a big cog, Wolf Tooth built in a wider alloy bearing surface on the cassette body, and well thought-out alignment of the new 45 teeth with those of the 11-40 big cog’s teeth (and to a lesser extent the 11-42 as well.) Then to ensure good shifting through the middle of the cluster, Wolf Tooth pulls out the stock 17 & 19 cogs and replaces them with a 18 tooth and the appropriate spacer for consistent ratio steps.
To break down the converted cassette ratios after a GC45 conversion, the 11-40 shifts to a 11-13-15-18-21-24-27-31-35-40-45 progression for a range boost from the stock 364% up to 409%; and the 11-42 transitions to a 11-13-15-18-21-24-28-32-37-42-45 spread improving over the original 382% range. Total weight for the converted XTR 11-40 would be 412g, XT 11-40 at 490g, and XT 11-42 at 510g.
The GC45 is US-made, in Wolf Tooth’s new headquarters in Savage, MN which we actually got a sneak peek of when we were there for a visit. Eagle eyed readers might have noticed that raw GC on the plate was a little larger than their current biggest. The 98g kit with 7075-T6 alloy GC45 cog, steel 18T replacement cog and alloy spacer will set you back $90. The kit is available now in black and red versions, with new blue and silver ones coming within a month.
Wolf Tooth says that their own Goatlink 11 is not needed for the conversion, when used with a long cage 11 speed derailleur, but is said to boost the crispness of shifts. They also hinted to us to keep an eye out this summer for bigger things, so maybe even bigger cogs are on the way, too…
