Can anyone tell me what part or set this round Technic piece goes to? I bought a large lot of LEGO and need help identifying this piece and or its set.
That's not the best picture in the world, but it appears to be a Wheel 31mm D. x 15mm Technic, either dark red or reddish-brown.  The dark red variation has appeared in a half-dozen Star Wars sets and two other sets, while the reddish-brown version has appeared in just one set.