No worries. Perhaps I'm being overly pedantic because it's unlikely that the OP is compiling on an architecture with 12 bit bytes (it doesn't look like an embedded program which is where you're most likely, these days, to encounter bytes with > 8 bits), but in the future who knows... maybe x86 will decide to have 12 or more bit bytes and the code would have to be rewritten if it was multiplying by 8. FWIW I thought of bytes as 8 bits for a long long time until I was programming a PIC with 12 bit bytes (edit: or maybe it was a 16 bits... can't remember) and I got... bitten (or is that byten or byted?)
Edit 2: It seems that there are de facto and no-so-defacto standards that say a byte is 8 bits (but that's not C's definition)