Yes, I know there is a road, been along it lots of times. However, you are staying in Hisaronu (about 20 minutes drive from Fethiye) and you want to hire a bike to ride between Fethiye & Calis. So, unless you are hiring you bike in Hisaronu, you will have to hire it in Fethiye to ride to Calis along the prom road. Fethiye is where the dolmus stops from Hisaronu, then you are a further 5 miles to Calis. The best advise is, do not hire in Hisaronu as you will not manage to ride the bike back. So, you could hire in Fethiye and ride to Calis, or you could get the water taxi from Fethiye to Calis and hire your bike there.