Re: speedhub 100Nm limit
are you referring to an internal gear hub? I have an 8-speed internal gear hub on a 26" wheel. I did'nt made any calculations like you did. I just installed and fire away... I don't think the HT engine can ruin the internal gear hub as long as the sprockets are geared properly.
Regardless if it's left or wrong, the opposite is always right.
Caution: This hobby is habit forming.