You don't need to take your bike or moto when traveling to Porec, there exist agency for renting it with vast choice of types, according to your preferences.
You can take quick tour of the city riding the bike, find yourself isolated beach outside the town or visit the surroundings of the town.
Trust me, there are alot of things to see and do in the surroundings of Porec.
Definitely great for biking....many, many trails as well as village roads which are beautiful and great for biking.
Look on their website to see more info.