Review- Wolf Tooth Components 40t Shimano GC Cog

By September 29, 2014 Uncategorized

wolf tooth

As the old saying goes there is more than one way to skin a cat.

Wolf Tooth Components is a small company ouf of Minnesota that has made its name with aftermarket XX1 style chainrings and conversion cogs.  They design and manufacture in-state and support a surprising number of World Cup XC racers who run a 1x Shimano drivetrain with drop stop chainrings and their GC conversion cogs.

The GC cog is basically a way to get the range of the vaunted SRAM 11 speed cassette with an existing 10 speed drivetrain.  It’s an adapted solution, so without adding an extra click you have to remove one of the smaller individual cassette cogs to make it all run.  I opted for the 40t rather than the 42t because it offered smaller gaps between gears and required less B screw tension.  All of that should mean slightly crisper shifts.  To make room for the 40t on my Shimano XT test cassette I had to remove the 15 or the 17, and honestly neither option was appealing as the jump between cogs was huge.  It shifted fine with either removed, but the difference in gear inches under power was hard to handle.

After fiddling around with a few different configurations I ordered Wolf Tooth’s 16t cog which essentially means removing the 15 and 17 so that the 16 sits in the middle.  The difference in spacing is pretty consistent through the range and following instructions for Shimano or SRAM means you can align the shift gates so they work properly.

While the 16t cog works well with either manufacturer the GC cog is specific to SRAM or Shimano and is not compatible with every cassette available (Neither Shimano SLX nor the SRAM 1080 will work) but options from the XT/X9 wheelhouse are both available.  Following these directions Wolf Tooth promises smooth, consistent shifting and after riding this setup for most of the summer I have to say that I fully agree.  If you didn’t know that this setup was installed you would never know from shifting quality or gear spacing that it was anything other than a normal cassette- and I have to say that’s a really good thing.

This ringing endorsement does not however cover all conversion setups.  I also tried a rival company’s conversion and had a miserable experience pushing my bike up usually rideable inclines because the chain would not stay in the lowest gear without jumping every pedal stroke.  Although it shifted consistently in the work stand it did not handle the torque loads of slow, technical climbs out on the trail- and that’s really the only thing it is designed to do.  No adjustment to the rear derailleur could be made to accomodate the new cog, nor did changing the chain have any impact, but the reinstalled Wolf Tooth worked flawlessly without any further adjustment.

Whether this is worth it for you depends on your application.  It works well for fatbikes, trail bikes, and even XC race rigs as long as you can handle your preferred terrain with a 30 or 32t chainring.   The additional chain required to handle the huge 40t means that you can only run this with a single front chainring and not 2x or 3x setups.  Most riders are looking to go to this to remove the additional chainrings so it should be a non-issue, but it’s worth mentioning.

This is a great way to get the same wide range as an 11 speed drivetrain with parts you already have.  It’s not cheap, but it is far more cost effective than an entirely new drivetrain, and as long as you get the additional 16t cog to go with it the whole setup is hard to beat.  With a clutchless rear derailleur, a ~32t narrow/wide chainring like Wolf Tooth’s Drop Stop or the Narrow Wide from RaceFace and the GC cog you’re most of the way there at a fraction of the cost.  That’s assuming you can readily run a 32 chainring on your current crankset and already own a compatible rear derailleur.

For more information visit


By September 26, 2014 Uncategorized

I’m not ready.

My first ‘cross race is this weekend at the Rapha Super Wonder Amazing Cross in Gloucester.  I’m pretty sure that’s the exact name of it, if you want to check me on it.

Joking aside it’s the current iteration of a race that’s been around for a while.  I think I last raced there in…maybe 2008.  Wow.  The bike is still not race-ready, and I’m personally in even worse shape.  I guess my fitness is OK, but I have done zero high intensity work recently and no ‘cross specific skills since 2012.  Definitely a recipe for success if ever there was one.

Work has been downright nuts, and we’re launching a huge project that has been years in the making. I expect it to be total bedlam for the next couple weeks so racing will not be in the cards.  I’ll be riding as much as I can for sanity’s sake and building up my volume again for this last push.

Realistically I’ll be starting in the back, and it’s training if nothing else.  Training on a grand stage, in a huge race where people are really out for blood and gunning for a result.  My goal is to finish on the lead lap and stay upright- that’s it.  From there it’ll be some skill work, training and whatnot to get ready for another round of ‘cross later this fall.

My next target is the Circumburke.  Last year was a bit of a dick show and I was too mad to really write about it, but I realize I have an axe to grind with that race and want to do it again.  I know what I’m in for- and I know how long I’ll be out there.  It’s a little more of an adventure, and even though I’m only planning on doing one 25 mile lap I know it’s going to be tough.  The course has one big climb early but there are really no recovery sections- it’s all on, all day, with not even fire roads to catch your breath.  The track is pretty soft- downright soggy in spots, and last year it was in the low 40′s with light hail.

So after Circumburke I’ll be digging into ‘cross for a few races.  Not all serious like, but just to avoid getting too fat in November.



The Numbers

By September 24, 2014 Uncategorized

photo (38)


I’m not a math guy.

At a certain point I really hated math.  Maybe it was because it required attention to detail in a way that I didn’t like, maybe I found it somehow mentally restrictive.  That sounds dumb, but math is the same thing one way or another every time.  I saw no spontaneity in math, no feel, no soul.  It was just numbers.

With Strava and power meters on both the road and mountain bikes I now have access to a ton of data, and I’ve been geeking out pretty hard on everything I can find.  Most interesting is the lap data for races, specifically that the guys who are killing individual segments or railing the fastest lap times aren’t the winners.  Pacing is key- and I’ve known that for a while, but seeing it recorded with more mid-race insight makes it much more obvious.

As I spin up my training again I’m thinking about all of this and trying to balance some ‘cross-specific training with the desire to give some local mouth breathers the old Strava bitch slap.  I pretty much never go all out on short segments, but at some point here I will.  Not for the sake of a workout, but for the sake of pride, or at least letting some of the locals know that I’m here.

And the numbers say I’m getting faster.