I am extremely new to cycling. I currently just bought my first bike since I was around 13 (I'm 27 now.) I purchased a Cannondale CAADX 105 from my LBS beginning of the week and will be picking it up Saturday. I've been reading recently about different crank sets and was curious what everyone has to say. The CAADX 105 currently has a 46/36 crank set and a 12-28. A friend of mine has a synapse which has the same rear but a 50/34 crank set. We are both at about the same fitness level. Am I going to have problems keeping up? If so would it be possible to put some sort of 50 or 53/46/34 crankset on the CAADX or Is that just a newbie question? I read a post about a 50x11 being 123 gear inches (not sure what that is in MPH?) would changing the rear cassette to something with an 11 tooth chain ring be more beneficial? Possibly a 50 or 53 big ring in front with an 11 in back? I'm more curious how much more speed I would be getting or is it just splitting hairs? How much faster could the same person get going with a 53x11 vs the 46x12. I suppose my real question is how much will I be held back by the lower gearing. If it's a significant amount what can I do to fix that mechanically on the bike. I am also curious about how big of a difference there is with the gear ratios of say 46x12, 50x12 and 53x12 and how much an 11 tooth chain ring would help. Tons of questions and I may have just puked them out all at once. Lol thanks to anyone that decides to tackle this tangled web of questions! Brent