For example, if I want to say "the performance of this bike could be affected/influenced by many things", is there a difference between these two words?
My gut feeling is that "affect" sounds better, but I cannot find evidence in dictionaries.
Learn English – the difference between “affect” and “influence”
word-choice
Best Answer
Influence has two main connotations that affect doesn't. The first is that of relation to process rather than state, so that something might affect a rock but rarely would circumstances arise where we could speak of that rock being influenced. The second, and weaker, connotation is of emotive response being involved; this is probably the connotation that makes it feel less appropriate to use in reference to a bike's performance. (We do speak of mechanistic processes being influenced, though, especially complex ones.)