one thing that goes against Cannondale is that they have proprietrary parts on them. This means that for certain things, you MUST take it to a shop that has the special tools that come from Cannondale. Not just any bike shop. Also means that you can't fix certain things yourself either, or order replacement parts from whomever. Headsest for sure, not sure about other parts, maybe the bottom bracket too.
Irulan
2015 Liv Intrigue 2
Pro Mongoose Titanium Singlespeed
2012 Trek Madone 4.6 Compact SRAM