While Garmin’s definitely most famous for its nuvi line of in-car navigation devices, the company has lately begun to branch out somewhat. It makes sense, really–with so many factory cars arriving with NAV built in, Garmin better start looking elsewhere for a steady stream of revenue. To that end, the company is teaming up with automotive powerhouse BMW in order to debut the Motorrad Navigator IV.The motorcycle-friendly GPS navigator is based around Garmin’s own zumo 660, and it’s said to take the best of Garmin’s