zacster

That's not right. On a smart trainer in simulation mode all of these are accounted for. While there is no wind, air resistance is built in to the speed calculation. If you get behind someone you'll get a drafting boost. And you certainly will feel the hills. This is in simulation mode. In ERG mode the program sets the wattage output no matter what your cadence or gearing is, so these things are taken out of the equation when it comes to feel, but are still reflected in speed. Even the different gear that you can earn will make a difference, some virtual bikes are faster than others, same with wheels.

How realistic this all will feel is where the trainer and software companies put their money. I did 2 laps of Central Park today in Zwift and it doesn't feel all that different than riding it IRL, except that Harlem and Museum hills both have exaggerated grades, but I think that is because of the intensity setting so they feel realistic. All that setting does is extend your gearing, it makes it feel easier but in reality it is only feels easier because you end up in a lower gear. Your speed is reduced. The problem I've always seen with this though is that I don't care about speed when I'm doing Zwift. But I did have a revelation this weekend when I rented a bike with much lower gearing than my own, 34/34 vs my own 34/26. I was in San Francisco and we know what SF is known for, hills. I'd have never made it up a few hills without that lowest gear, but instead I could spin up. Even a less steep but longer hill up in Marin was made much easier for me with the lower gearing. I'd have made it up with my own bike but it was more relaxed with the rental. Zwift does this for me in the software, and that's a lot cheaper than buying a new cassette and derailleur that will take it.