Speed Tests: Learn How Zwift’s Mountain Bikes Perform

Zwift’s mountain bikes perform better in the dirt than road bikes, thanks to a lower rolling resistance (Crr). But how do the individual mountain bikes perform against each other?

Here are the mountain bikes currently available (not shown: the stock Zwift Mountain bike):

We ran extensive tests to find out how each bike performs on climbs, flats, and on the Jungle Circuit. Here are the results…

Flat Pavement Performance

Here’s how each mountain bike performed over two laps of our Tempus Fugit test segment (300 watts steady, 75kg rider):

1. Scott Spark RC World Cup: 55:40
2. Trek Supercaliber: 55:41
3. Scott Spark RC: 55:43
4. Specialized Epic S-Works: 55:44
5. Canyon Lux: 55:45
6. Zwift Mountain: 55:53

The Spark World Cup just edges out the Supercaliber by a consistent 1 second, so we give it the win in this test.

By comparison, the fastest road bikes complete the test route in 50:25, while the slowest road bikes (Zwift Steel with 32mm carbon wheels) complete it in 51:40. So if you’re riding an all-pavement race, you definitely don’t want to be riding a mountain bike, because mountain bike wheels roll much slower on tarmac than road wheels due to Zwift’s Crr settings.

The fastest gravel bikes complete the test route in 53:47, which is what you would expect: the mountain bikes’ big knobbies and poor aero values make them slower than road or gravel rigs on pavement.

But how do the mountain bikes perform in other settings?

Climb Performance

Here’s how the mountain bikes performed up the big Alpe du Zwift climb:

1. Scott Spark RC World Cup: 55:21
2. Trek Supercaliber: 55:25
3. Scott Spark RC: 55:31
4. Specialized Epic S-Works: 55:36
5. Canyon Lux: 55:42
6. Zwift Mountain: 55:53

Again the Spark RC World Cup comes out on top, well ahead of the competition on climbs. It’s certainly a lightweight rig!

The fastest road bikes climb the Alpe in 48:42, while the slower (Zwift Steel with 32mm carbon wheels) complete it in 49:57. So the heavy mountain bikes are well behind, as they should be. Because mountain bikes are heavy, they roll slower, and physics matter!

Jungle Performance

What about the dirt? This is where knobby tires should excel, and indeed they do. Here’s how the mountain bikes perform on one lap of the Jungle Circuit:

1. Scott Spark RC World Cup: 13:18
2. Trek Supercaliber: 13:18
3. Specialized Epic S-Works: 13:19
4. Canyon Lux: 13:19
5. Scott Spark RC: 13:19
6. Zwift Mountain: 13:21

The four brand-name bikes turn in nearly identical performances, with the stock Zwift Mountain bike a few seconds behind.

The faster road bikes complete a jungle lap in around 13:35, while the gravel bikes do it in 13:20. But our mountain bikes shred some gnar and lay the hurt on all those skinny-tired, rigid-forked rigs!

MTB Conclusions

Zwifters really only ride mountain bikes on dirt routes – unless you’re looking for a good workout in a group ride on the tarmac! So which bike should you choose in the Mayan Jungle?

Clearly the Scott Spark RC World Cup is the standout performer here, as it will outperform the other frames on the crucial uphill portion of the circuit while keeping pace on the flats and descents.

Your Thoughts

Have you tried the new Supercaliber? What’s your go-to MTB rig on Zwift? Share below!