Friction of the bike on the smart trainer in Zwift.
1. Pedal bearings, bearing quality
2. Bottom bracket, bearing quality
3. Derailleur pulleys, use ball bearings
4. Size of the chainrings and cassette, more teeth reduces chain friction
5. Chain, quality (Dura Ace) + lubrication

HE'S BACK!!!!!!!

You’re back 🎉

Excellent video!

Good tips!

Great tips but Zwift won’t fulfill my order so I can implement them. 😂

102kg is my problem

Not the legs, HR gets too high.

A small nuance to your commentary about never starting a climb at the front and that  "sag climbing absolutely doesn't work in Zwift"

Agreed  - don't put your nose in the wind before the climb and instead make sure you carry draft speed into the bottom BUT . . . if it's a large somewhat strung out group, there is absolutely value in being 2nd, 3rd, 4th wheel at the front when the climb begins and then slowly sagging to the back of the group over the duration of the climb.  Once at the top, you can then drafting back into the blob on the descent.  Being able to drift from from the front to the back can keep the overall effort to stay attached to the group much lower than someone who starts at the back and tries to hold on.  Sag climbing absolutely does work in Zwift . . . when done correctly.

Outside of that quibble, good overall advice. 👍