Is your bike bluetooth enabled at all? Might be working checking out if it’s compatible with this app: https://www.qzfitness.com/ which could then send the metrics to Startona
It's not, no - it has a rinky-dink little computer with a simple 7-segment LCD, which is connected to whatever in the bike is measuring rotations via a 3.5mm jack. I did experiment with seeing if I could read a signal from it via a mic input so I could hack together a more advanced display but didn't have any luck.
I've just had a look for ways to adapt it though, and found BitGym [0] which doesn't require a connection to the bike at all - you just place it on the handlebars and it measures your cadence with the front-facing camera somehow. That would be a neat feature for Startona. Maybe you could even measure it via the accelerometer? FFT the lateral motion of the device to find the frequency of movement? Maybe it wouldn't be strong enough but it would be an interesting experiment
It should be fairly straightforward to measure the cadence in the way you describe, but you would still need a way to measure input speed. Startona uses a physics simulation to calculate the player's speed based on the power input since this gives the most accurate results. In case power is not available, the game uses speed as a fallback. Although, it would be fun to add a way to connect an Arduino-based solution via USB so people can homebrew their own speed measuring systems (with hall sensors or similar). I am open to adding that option if enough people ask for it.
You could try to use a Bluetooth speed sensor like the "Wahoo RPM Speed Sensor" if your home trainer somehow allows you to fasten it to it's flywheel - if not, you would still have the option to put your bike on a cheap roller. That way the game would work, but you would only get a limited experience since only the high-end rollers support erg mode. At that point, you have come full circle and it may be cheaper to opt for an entry-level hub trainer like an Elite Suito.
