With a classic trainer, speed and cadence wahoo sensors, when a hill starts, the speed drops very very low, I’ve tried to shift gears to make it more difficult and simulate my way up but I don’t really see zwift showing an improvement with me doing that, it’s there something you recommend to do that works better for climbing with the classic trainer? Thanks.
What cadence are you at during the hill and your w/kg?
Zwift takes the wheel speed broadcast by your speed sensor and the power curve (see below) of the trainer you select on the Pairing Screen and converts that to virtual watts, also known as “zPower”.
Your in-game speed is determined by those watts, the weight and height entered, in-game bike frame used, in-game drafting (Tri and TT bikes get no drafting boost), in-game wheel set, in-game road surface, and in-game virtual elevation changes.
Activating a Power Up such as the Truck (draft boost), Feather (weight reduction), or Helmet (aero boost) can further alter your in-game speed for a short duration.
This is not a real trainer curve, only to demonstrate the concept.
Example: Your wheel turn at 40 km/h then Zwift will use the curve and determine your Power as 200w. Using a set of complex equations taking your weight, height, road incline , rolling resistance and other factors in to account Zwift will calculate your virtual Speed.
So that 200w can be 45km/h on a flat road or 12km/h on a hill.