Although 90 kilometres may seem a bit of a stretch, this ride is almost completely flat and, with a tail wind, can be completed in a single day. The first leg of this trip takes you along state highway 2; busy, but safe enough, with mostly wide road margins through to Te Puke (a pleasant service town with camping, supermarket & cafés).
Soon after Te Puke the Tauranga/Rotorua traffic turns off onto highway 33 while you continue along the now considerably quieter highway 2. Here you wind your way a further 20 or so kilometres through farm land till you reach the coast. There are several camping options along the coast, at Pikowai, Matatā (store, café) and Thornton.
Whakatāne is a large-ish town and has everything you need. The campground here (there is only one) is very pleasant indeed - set in a reserve along the banks of the Whakatāne River and just a few minutes from town.
About 50 km off-shore from Whakatāne is Whakaari / White Island one of New Zealand's most active volcanos and the scene of a devastating 2019 eruption which tragically claimed 22 lives. The island is visible right along the cape, often covered in a plume of smoke.