Police say both men involved in a fatal motorcycle crash near Hamilton on Friday weren't wearing helmets.

34-year old Hamilton man Wayde Thomas died after two motorbikes collided near Temple View, the other motorcyclist is in Waikato Hospital in a serious condition.

Inspector Dana McDonald says neither man was wearing a crash helmet or safety gear.

He says the crash wasn't witnessed by anyone else and it's too early to say if speed or alcohol were involved.

The Serious Crash Unit are investigating.