Rollers + Speed/Cadence sensor

Rollers + Saris Speed/Cadence sensor
I have CycleOps Al rollers and use my mountain bike with 29” 2.25 wheels. I have my correct weight in and have selected unspecified rollers. Yet my rider avatar hardly moves when I ride. I battle to get over 10km/hr and over 30 watts. Please can someone shed some light! It’s really frustrating!

Hi Brandon

Those rollers does not provide a lot of resistance. According to Saris you should get 200w at about 40km/h wheel speed. I don’t thing with MTB gearing you will get 40km/h.

I would assume you should get at least 20km/h and if the resistance is linear you should get 100w.

I don’t know the power curve for the unsupported Zwift trainer.

Is it possible that you have the speed and cadence sensors reversed (either on the bike or on the pairing screen)? If what Zwift thinks is your speed sensor is actually measuring your cadence the RPMs would be far less than your wheel is turning, resulting in lower perceived watts.