If you got the attention of a potential investor in a random setting you can decide how to use your 2 minutes. One option is the 1-way monologue, where every single one of these precious 120 seconds is filled with information and facts.
The other option is pitch your idea briefly, read someone’s face, interpret a quick question and adjust your story to the concern you see.
I think the second approach is better. Maybe you lose 30 seconds of airtime, but the other 90 seconds are definitely more effective.