11-speed chains have a narrower external width than 10-speed chains and are therefore sufficiently thin to operate on an Advent X cassette without rubbing against the cogs.
One can argue that the narrowness of the chain could result in a slower response time, but in practice, the difference shouldn’t be perceivable.
Nonetheless, using the original 10-speed chain is still recommended if possible.
10-speed chains are thicker and thus stronger than 11-speed models when all parameters such as materials and quality are equal.
FAQ: What is Advent X?
Advent X is a 1×10 mountain bike groupset produced by microSHIFT. It includes a massive 11-48 cassette that weighs only 424g/14.96oz.
Compatibility Between 11-speed Chains and 10-speed Cassettes
In this case, we are analyzing the compatibility of an 11-speed chain with a 10-speed MTB groupset.
It’s necessary to focus on two elements – the cassette and the potential chainring (the chainring is not part of the group set).
The cassette in question is a 10-speed MTB model with standard spacing matching that of Shimano’s HG 10-speed MTB models.
Normally, a 10-speed chain will be paired with this cassette, but an 11-speed model can work too.
Why?
Chains have two widths – inner and outer.
The inner width is the distance between the inner plates; the outer width is the distance between the external plates (image below).
The inner width of a chain changes very little with each gear increase.
However, the external width of the chain decreases as the number of cogs on a cassette climbs.
This happens because cassette cogs get closer to one another with each gear increase while preserving their thickness.
This “shrinkage” is strategic as it makes one hub compatible with multiple cassettes. For example, it’s possible to install a 10-speed cassette on an 8-speed hub precisely thanks to this engineering.
The chain has to reflect the reduced spacing between the cogs and thus gets thinner as the number of gears grows. If the chain’s dimensions remain the same, the outer plates will rub against the adjacent cogs.
Since the overall thickness of the sprockets remains the same, the only way to make the chain thinner is to thin out the outer plates.
In other words, an 11-speed chain has the same inner width as a 10-speed chain but comes with thinner outer plates and narrower external width.
The table below contains the width of most chains out there:
| Number of Speeds | Inner/Roller Width | Outer width |
| 7 | 2.38mm | 7.3mm (Shimano), 7.1mm (SRAM) |
| 8 | 2.38mm | 7.3mm (Shimano), 7.1mm (SRAM) |
| 9 | 2.18mm | 6.5-7mm |
| 10 | 2.18mm | 5.88-6mm |
| 11 | 2.18mm | 5.5-5.6mm |
| 12 | 2.18mm | 5.3mm |
As you can see, 11 and 10-speed chains have the same inner width (2.18mm) while the outer width differs by approximately 0.2-0.5mm.
The difference is very small, about 6.9%, and is therefore not enough to cause massive latency due to the extra space that the derailleur has to travel to reach it.
The next table shows the cog pitch (center-to-center distance between two cogs) and the sprocket thicknesses of various cassettes.
| Number of Speeds | Cog Pitch | Sprocket Thickness |
| 8 | 4.8mm | 1.85mm |
| 9 | 4.35mm | 1.78mm |
| 10 | 3.95mm | 1.6mm |
| 11 | 3.9mm | 1.6mm |
As you can see, the cog pitch of 10 and 11-speed cassettes is very close. The sprocket thickness is identical.
Chain and Chainring Compatability
The Advent X system is made for a 1x drivetrain. Thus, it’s necessary to combine it with a chainring designed specifically for 1x drivetrains.
The most common option is a narrow-wide chainring.
Narrow-wide chainrings were specifically developed to improve chain retention on 1x drivetrains via teeth of alternating width – one is narrow, and the next is wide.
This pattern is specifically chosen to match the varying width of a chain.
The wide teeth slide between the outer plates whereas the narrow ones go between the inner plates.
As a result, the chain is less likely to drop.
The vast majority of narrow-wide chainrings are designed for 9/10/11/12 as those chains have matching inner widths.
Thus, if you’re using a narrow-wide chainring with the 11-speed chain, the combination will work just fine.
Summary: What You Need To Know
- AdventX is a 10-speed MTB system.
- An 11-speed chain is compatible with 10-speed MTB cassettes. 11-speed chains are slightly narrower than 10-speed models while having the same internal width.
- The downsides of combining an 11-speed chain with a 10-speed cassette are slow shifting (potentially) and a higher chance of chain failure (10-speed chains are thicker and thus can be stronger than 11-speed models.)
