Yogyakarta is truly an affordable paradise for travelers. It's enough with 20$/day: 5$ for bed, 5$ for a motorbike; the rest is for food, sightseeing, and shopping. Here is complete information on motorbike / motorcycle rental in Yogyakarta / Jogja.
YogYES.com (www.yogyes.com) An exceptional website, full of rich content about the city and its culture, with numerous tips for travellers. ~ Lonely Planet
Visit Yogyakarta, http://www.yogyes.com/, is an extremely useful English-language Web site. ~ The Washington Post