Hi everyone, I'm a newbie here. And I just purchased an older specialized road bike off of craigslist and wanted to get a few new things for it and there is good deals on ebay but how do I know if its compatable with my bike for example I know its a 1" headset and I seen 1" threadless necks do I need a new fork or jus a threadless headset to go with the neck. Also cranks I have all shimano 105 components how do I find out what cranks will work for me. Thanks everyone I appreciate any and all advice.