Keeping modernish (5-15 years old) bikes running and upgrading them is one of the most confusing processes I have gone through. Many times I have gone to purch

Keeping modernish (5-15 years old) bikes running and upgrading them is one of the most confusing processes I have gone through. Many times I have gone to purchase a replacement part or upgrade online, only to put it off 3-5 times because I'm not sure if it fits my bike. Anyone want to work with me on a project with good compatibility guides and affiliate fees?