26” Hardtail MTB on Saris Fluid2

Hi there. Total noob Zwifter here

I’ve been searching the forum for answers but can’t find what I’m looking for. Apologies if this has been asked many times before

So, I’m a keen mountain biker, riding the trails every weekend. Thought I’d give Zwift a go just to get the legs spinning mid-week. I have an old 26” hardtail gathering dust in my garage so am using that on a Saris Fluid2 trainer with speed sensor attached to the hub

Selected 26 x 2” wheels when connecting to the sensor. Yes they’re nobly tyres and make a horrendous noise

Chose the MTB frame in the Zwift garage because, you know, I ride MTB

Did my first ride this evening and it was one of the hardest rides I’ve ever done!

Only chose a simple 16 minute workout around Richmond. Pedalling like crazy in highest gear would only achieve around 200W and an average speed of 8mph. The game kept pushing me to pedal harder but there was nothing left to give

Also, the avatar kept coming to a standstill even though I was pedalling hard. If I slowed down and built the speed back up again the avatar would start moving. This kept happening throughout the 16 minute ride

Something isn’t right. Ive set up my correct height, age, weight etc, correct wheel size, selected the Saris Fluid2, and have the tyre correctly positioned on the trainer wheel

Any idea what I’m doing wrong and need to do to correct the issue? Thanks


I’m not sure on the lack of forward progress, but when I first started Zwifting with a wheel-on trainer I tried to use one of my retro MTBs and the gearing simply didn’t work. Like you, I was just spinning and spinning and spinning to the point where it wasn’t working.

Had to drag an old road bike out of storage to solve it.

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Thanks for your reply. I’ve ordered a slick tyre, changed my avatars ‘garage’ bike to a road bike rather than MTB, I’ll see if that makes a difference and persevere with the old retro gearing for now :sweat_smile:

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Don’t worry. If you do end up having to use a road bike, you can still stay true to yourself by fitting some black plastic flats on it like I have :smiley:

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Had similar issues when setting up my kid on their mtb, also on a Fluid2.

I ended up playing around with wheel size and the roller pressure against the tire, took a few tries but we found a combo that gave them a realistic speed.

As for the avatar stopping constantly I found they had to pedal a steady speed and smooth pedal stroke, once we solved the power output/avatar speed then this issue pretty much went away.

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Have you started wearing Lycra yet ? :smile:

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I’ll have another fiddle later this evening. I engaged the locking ‘clutch’ tight against the tyre but it takes a massive amount of effort to hold even a steady pace, and the screen shows I’m only giving around 80W (and slowly travelling at 7mph) which is a bit off putting whist I’m bursting lungs and sweating more than a monsoon downpour!

An update …

Did another workout, just a simple 20 minute ride. All over the place again, Sometimes fast, sometimes slow. Hit over 1200W, but going up the slightest incline I was reduced to around 60W and only moved at 2mph

Avatar kept coming to a standstill again even though I was pedalling in highest gear

So, after being annoyed, I downloaded Rouvy to see if the same happened there

Zero issues with Rouvy. Could ride at a nice steady pace, realistic speed, realistic inclines, could keep the pace and ride with the pack. Profile was set up in the same manner, Saris Fluid2 trainer, 26 x 2 wheel, same age / weight / height etc

So, the issue can’t be with the sensors or the gearing of my bike, it must be with the software. Shame