Advise please, I've a 50/34 at front with 12/23 cassette. Some of the hills round Perthshire are pretty steep. I've only had to get off and push once up part of Glen Quaich but was wondering if I change to a 12/25 (27) will I really notice a difference. Second question bike has Fulcrum 7's thinking of upgrade to 3's or any suggestions.