RE: I NEED HELP!!!!!!!!
You were taking apart the motor????
Sounds like it's a silicone/rubber o-ring to keep dirt and water out but I have no idea where it would have come from. Best guesses would be: if it's a small diameter then it's probably surrounding a shaft (like a shock or differential o-ring); medium diameter then it may be a bearing seal (just try to press it back in); larger diameter then it's probably used as a gasket to seal cases and/or wiring.