(1) Subject to subsection (2) there is in a contract for sale a warranty by the seller that (a) the title conveyed shall be good, and its transfer rightful; and (b) the goods shall be delivered free from any security interest or other lien or encumbrance of which the buyer at the time of contracting has no knowledge. (2) A warranty under subsection (1) will be excluded or modified only by specific language or by circumstances which give the buyer reason to know that the person selling does not claim