I have a 4300D and I plan to upgrade the frame to a slightly used 8 series alu frame (most of the components I have already upgraded so I can use them). I have some questions:
- Apart from the paint work are there major differences (e.g. geometry) between the comparable frames from different years (not decades, naturally, but for example will a 2012 frame be much different then a 2009)?
- Is a 19.5 size 8 series frame is equivalent to a 19.5 size 4 series frame?
- Is there any difference in the frame between a Trek 8000 and 8500?
- Would you prefer above the top tube or below the top tube cable routing (the only visible difference between frames from 2009 and 2010)

Thanks for any help.