This seems to me to be a bit of a grey area as I "aquired" a workshop CD for my BMW but I'm sure that Beemer themselves hold the copyright. ..... To me it's piracy, pure and simple. I'd not put it in the public domain. Just my tuppence worth, no offence intended.
There is no grey area, if Yamaha or BMW hold the copyright they can pursue the people doing the copying, the people hosting the website and possibly even the buyers. Ford lost something around the £50,000 mark using Mirror Group text and pictures in a training manual without permission (and the stupid thing is, if their advertising buyer had asked they'd have been given permission). The company I was working for at the time was invited to join the action as they'd used our stuff too, but you don't sue your big customers unless they can't buy elsewhere. Big publishers employ web searches to keep their legal departments profitable. You'll now find every photocopier in every vehicle plant in the country has a notice saying you may not copy copyrighted material.
US law is (I believe) different, vehicle repair information has to be available outside the dealer network. If the manual has a US address or number on it, ot may be in the public domain, in which case there is not copywrite.
Now, the chances of Yamaha or BMW going after the club or shedbrewed or the people selling on e-bay, is probably quite small, but would you bet your house on it?
Andy
A