Measuring chain length
I'm doing my first chain replacement and I'm not certain how to measure the chain length.
The guy at the LBS advised threading the chain and finding a length where
1) when on the largest front&back gears, the derailleur isn't too tight (hitting cogs), and
2) when on the smallest front&back gears, the derailleur isn't too loose.
However, the Sheldon Brown site simply suggests running the chain around the largest gears and using that length. I'm worried that might not be loose enough when threaded around the derailleur, though.
What to do?
Thanks