Can I ride in the mountains with such a cassette without any problems? - This is one of the most common questions we hear when discussing gravel bikes with our customers.
Gearing is a very personal topic and every rider is entitled to his/her opinion. It is impossible to comment on it in any way if we have not tested at least a few options first-hand.
This leads to a lot of consternation at the initial choices. Let us try to clarify the situation a little.
What is the gear ratio on a bicycle?
If you are just starting to ride, to get more comfortable with the topic mentioned above, it would be advisable to find out what such terms as gear ratio, gears or gear range are.
The first issue is easiest to understand using the example of a fixed gear - in this case, we have only one sprocket at the front and one at the back - the bigger the front/ the smaller the rear sprocket, the more revolutions of the wheel we will get with one turn of the crank. It will be harder to pedal, but you will not have to spin as fast.
The other way round is the opposite. The smaller the front/larger the rear sprocket, the lighter it will be, but you will have to pedal faster.
The first variant is bigger/higher gears, which will be useful at high speeds and on descents, and the second is smaller/lower gears, which are useful on ascents.
The key here will be to maintain the right cadence (number of revolutions of the crank per minute), which will be the most comfortable and effective, and this oscillates between 70-90 RPM
In the case of a fixed gear, we have only one gear, therefore it must be versatile enough for us to pedal freely at our typical speeds. You can read more about this issue here.
Gearing on a gravel bike
Let's transfer this concept to gravel bikes. We still use one gear ratio at a time. However, we have many more options to choose from as the cassette consists of not 1 but 9, 10 or 11 sprockets. In addition, drivetrains with several front chainrings, double and, in older models, triple the number of possible combinations (some are repeated, of course). However, most people still worry about 'running out' of high or low gears.
How it used to be - double and triple-chainring drivetrains
Why are people ditching the front derailleur?
While 3X drivetrains used to win with the number of gears, they were plagued by several serious problems. Front derailleurs simply didn't do well with three chainrings. This was of course most noticeable off-road, in more challenging conditions.
The consensus in the road world today is two chainrings, while in the case of gravels, more and more companies are producing models that are only suitable for drives with one front chainring. Why?
- Reliability - fewer sprockets, fewer shifters and less derailleur gearing, results in a more durable drivetrain and better operating performance
- Ease of use - in the field, we often do not have time to think about whether we are cross-chaining. 1x11 solves this problem.
- Precision and chain holding - while modern 2x drives do well on the road, they are lacking when riding off-road. A 1x drivetrain simply ensures that the chain will not fall off. Practically never. Several factors contribute to this - no derailleur, a narrow-wide chainring that holds the chain tighter, and provides more tension on the aforementioned thanks to the clutch.
- Tyre clearance - the front derailleur and many front sprockets effectively limit the clearance for the rear tyre.
You can read more about this issue here.
The possibilities and comfort of using 1x drivetrains, especially off-road, effectively overshadow the issue of gear range, but of course, everyone would like to have the best of both worlds. So what can we do?
Today's gravel bike options - the gear range
The current standard for 1x11 gravel drivetrains is an 11-42t cassette and a 40t or 42t front chainring. This is how it looks in the standard versions of the groupsets proposed by both SRAM and Shimano.
In practice, it turns out that both Shimano GRX and SRAM derailleurs handle up to 11-46t without any problems. This gives us a range of 418% (quotient of the smallest and largest cassette sprocket).
Such a value is sufficient both for most "normal" climbs and descents, in applications typical for gravel bikes. But what if you're riding a loaded bike in the mountains? In such situations, the 46t slowly stops being comfortable.
The obvious solution to this problem is to put on a smaller front chainring, but in this case, our descending capabilities will suffer, and comfortably keeping pace with your friends on the road bikes can be problematic. However, cyclists have also found an answer to this.
Mullet drivetrain - ideal for a gravel bike?
The so-called mullet drivetrain comes to the rescue, in other words, a combination of gravel/road shifters with a cassette and possibly an MTB derailleur. This opens the door to the world of wide-range cassettes. However, in our opinion, such a combination is not ideal, because MTB derailleurs have a different cable pull than road/gravel derailleurs and therefore are not compatible with road shifters.
This means the need for solutions such as Tanpan, which solve this problem. A derailleur extension (Goatlink from Wolftooth) may be needed in this case to fit a wide-range cassette anyway. Another way is to buy an electronic group, such as SRAM AXS, which doesn't care about the problem of different cable pulls. In this case, however, the expense is enormous.
So we have the choice of combining with various add-ons, which do not look ideal and are another component that can fail or spending much more on a wireless groupset. Or maybe there are other possibilities?
How to get a wide range of gears - the best solution
So what will be the most "clean" looking option without costing as much as many bicycles at the same time?
If you prefer two derailleurs, for example, the GRX RX800 2x11 group, a good option would be to use the Roadlink from Wolftooth and an 11-42t cassette. With a 46-30t crankset you get a really powerful combination.
If you want to have only one chainring at the front, in our opinion this course of action will make the most sense:
Replacing the cassette with an 11-46t one - this will give you lower gear ratios, which will help significantly on climbs. If, on the other hand, you are missing heavier gears, putting on a 44t top instead of 42t or 40t will give you a 4.0 gear ratio instead of 3.82 (42t) or 3.64 (40t) while maintaining similarly light gears.
Replacing the hub driver body with SRAM XD and the cassette with 10-46t - the next step if you are not satisfied with option No. 1. In this case, we increase the high gear range even more - a 40t chainring will give us the biggest gear ratio of 4.0 and the smallest of 0.87. Additionally, the SRAM XD system solves the problem of the cassette "biting" into the hub driver body and is slightly lighter.
A cassette with a very large range - 10-50t - in this case, we can either use a derailleur extension and/or MTB derailleurs+Tanpan or (which in our opinion is a better option) use a custom derailleur cage from Garbaruk. This solution skips the whole MTB derailleur fitting operation and will provide precise shifting with normal SRAM Apex/Rival/Force or Shimano GRX drivetrain. In this case, the 44t chainring will give us similar small gearing as the 40t in option 2. The upper range however, will be significantly increased. If we go to even heavier terrain, it is enough to put on a 42t chainring. In this option, we will not lack gears on either side.
Would you like to buy a gravel bike that can cope with all conditions? Write to us!