Need smaller gears on your MTB to go faster?
Upfront is the chainrings. Previously there were 3x and 2x systems. But these days everything is 1x. so you will likely have single chainring upfront. And at the back we refer to the sprockets on the cassette. So, the Smallest sprocket will be around 9,10,11 and the largest one will be a 50,51,52. Depending on whether you use HG or XD (SRAM) or Microspline (Shimano) free bodies. Let’s delve into the details. Because that is where the devil is hiding. Or not.
AT FIRST, on the previous bike for reference
Because we all want to go faster! On my previous MTB (older EPIC comp) it was still a 2x upfront that came with a 22/36T. Which I later swopped for a 24/38T up front. And the cassette at the back was a 11-36t. Which means it had a 38/11=3.4545 ratio in the smallest cog at the back for going fast. And a 22/36=0.61 smallest ratio for climbing. you can easily grab the results from a bike gear calculator tool like bikecalc.com/archives/gear-ratios
NOW, on the 12 speed HG freebody
Enter the new 12spd EPIC with a 1x SRAM NX drivetrain. The single ring up front is a 36T (already bigger than the 32 or 34T of most) and the cassette is a 11-50t at the back. Which means the easiest gear is currently 36/50=0.72 smallest ratio for climbing. Which is already a whopping 18% more difficult than before. And the smallest ratio is down to 36/11=3.2727. And that is about 5-6% slower than before. So yes, the 1x system is neat and such. But in this application, it is slower and harder to climb than what I had before.
NEW, on the 12 speed XD freebody
Now my cycling improved a bit over the years. And I am not concerned about the climbing gears. Confident that I will make it up the hill, despite more power needed to do so. But the ‘fast’ gear is the one that really gets me. And you cannot go lower than an 11 sprocket at the back on the current HG freebody. So that will be changed to a XD driver. Which is newer and simpler and smaller. And allows you to for a smaller sprocket at the back. Typically 10t, but there is also a 9t model on Takelot. Which is what I am going for. Results below.
RESULTS on the new XD driver and DT Swiss Formula freebody from Specialized
So the new setup will still be the same 36T chainring, but with a 9-50t cassette. And that changes the figures to a whopping 36/9=4.00(!) for the fastest gear. Which is an increase of 22% over the current and almost 16% faster than in the old bike example at the top. So I am really looking forward to this one. Climbing stays the same at 36/50=0.72. Which means I have to stay fit.
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And there you have it. Went in today. Can’t wait to feel the result. THEN I will use #bicyclecouriers to send my bicycle off on the next adventure!
