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):
- Scott Spark RC World Cup: 55:40
- Trek Supercaliber: 55:41
- Scott Spark RC: 55:43
- Specialized Epic S-Works: 55:44
- Canyon Lux: 55:45
- 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:
- Scott Spark RC World Cup: 55:21
- Trek Supercaliber: 55:25
- Scott Spark RC: 55:31
- Specialized Epic S-Works: 55:36
- Canyon Lux: 55:42
- 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:
- Scott Spark RC World Cup: 13:55
- Trek Supercaliber: 13:55
- Specialized Epic S-Works: 13:56
- Canyon Lux: 13:56
- Scott Spark RC: 13:56
- Zwift Mountain: 13:58
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 15 minutes flat, while the gravel bikes do it in 14:11. 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!
Awesome review, and posted quickly! Supercaliber was only released days ago and I was curious about its performance! Thanks for the review, looks like it will be added to my shop shortly!
I hope it doesn’t gain weight, lose aero, and increase in price at the next Zwift update though (cough Canyon cough). 🙂
Like Kyle said, I wouldn’t purchase it straight away in case Specialized crack the sads again.
It will be the best mtb in the game…. for 2 months. Then get nerfed like all the other bike releases. 🙂 Zwift keeping the speed test updates busy for Eric.
How do mountain bikes perform on the cobbles?
I’d been wondering about this, so thanks for the work as ever!
What is the point of including the gravel bikes if they’re not even fastest on the dirt though? In the real world the only time a mountain bike is faster than a gravel bike is in deep wet mud.
A question we’ve all asked, for sure…
not quite true-on rough bumpy/rocky/rooty terrain a full-susser is faster than a gravel bike, and it doesnt take much mud for some wide knobblys with a fast centre tred to have an advantage. Gravel bikes are good for dirt tracks and switching terrain. Horses for courses!
Not sure they have differentiated these enough. So there’s only one place u should use an MTB and there’s only 3 seconds between them – why spend the drops on an ‘occasional’ bike.
I’m keeping mine for kit I will use more and will make more difference.
This is my feeling. If you don’t ride the jungle circuit often, it’s probably not worth spending drops on expensive MTBs for a few seconds of speed.
Great review though Eric, I wanted something to tell me if it was worth investing for the Monday night dirt iTT I have started doing. This answers that.
Can you ride MTB trails without the steering pad?
You have to steer on Repack Ridge. But you don’t need a smart plate. Or even a plate really. You can use the companion app mounted on your handlebars to handle the communication between your bike and Zwift app. I use an old iPhone5 and it works pretty good. You have to be able to turn the front wheel though. I don’t have a plate so I just use my wheel on a towel on hardwood floor and it works fine.
Great, thanks
Hi Eric, thank you for all your work. Do you and Ben have any plans to adjust the jungle segments on Veloviewer to remove times from when road bikes hooned round at silly paces?
With TdZ Stage 7 on The Jungle Circuit, is the best set up to go gravel from the start for the 2km lead in or road then MTB change when you hit the dirt?
Hi Eric, I am wondering the same. But I think the lead in is 5.7 km long. Bike choice or ?bike switch? could make a significant difference in that stage. What do you think?
Nah, bike switch isn’t worth it. You’ve only get a couple km of tarmac before the dirt begins. Not worth losing 10s or more switching bikes.
The Bambino Fondo, though, has its middle third on the Jungle dirt. There, I presume, a smart rider would switch bikes. What would you recommend?
If you’re goign to switch, use your fastest road bike on the road, and pretty much any MTB on the gravel. If I were doing that route, I doub’t I’d bother switching. If you are ‘competing’, it probably isn’t worth the time you’ll lose (10-20 seconds, depending on how fast you move around in your garage). If you aren’t competing, just relax and enjoy the ride on whatever bike you like to ride.
I just checked the route – only 8km of the 33km Bambino route is on the gravel roads. Personally, I wouldn’t switch. If I were to switch I’d use the fastest MTB you have unlocked for that section, and the fastest road bike you have for the rest. Keep in mind, you have to switch twice – so 20-40 seconds of stopped time is going to be significant (if you are trying to be competitive in terms of finish time).
FYI I switched (just for fun) from road to MTB at the Jungle (posn 318) came out the Jungle at posn 253. Then switched back to road & finished at posn 248. Read into this what you will. I counted only 10 MTB in the Jungle that I saw!!
I changed to MTB in the Jungle today too and gained about 50 positions total be the end of the ride after switching back to road bike = juice was worth the squeeze!
I did that with a gravel bike yesterday… went from 250th to 170th. But I was just doing a Z2 ride…
I was about to spend some drops on the Spark RC, since I’m riding one of those IRL, but now Scott has launched a new version IRL. Has anyone heard any rumours about if we’re getting the new version in Zwift as well?
Haven’t heard any rumors. But that new internal rear shock looks pretty sweet!
Compared TdZ stage 4 (Jan, 2022), Serpentine 8 route, one on road bike, one on mountain bike:
Canyon Aeroroad + Zipp 808 = 49:28 https://zwiftpower.com/events.php?zid=2556831
Zwift Mountain Bike = 43:19 https://zwiftpower.com/events.php?zid=2556791
The road bike event had fewer riders, so possibly some drag considerations, but otherwise rides (power) were identical.
I’m not planning to ride a mtn bike on a road bike course and on dirt, 3 second advantage for the Trek not worth the drops in my opinion.