Oliver Brock made the avian discovery last week, less than a day after he last used his bike.
Mr Brock chose to leave the bird in its nest, and set up a camera so he could watch its progress from his lounge.
Mr Brock said his motorbike is a 2017 Kawasaki Versys 650 SE, with the nest built inside the front fairing where the headlights are.
The Guernseyman said the eggs are visible and they aren’t brooding yet, so he’s expecting a short wait at least before anything hatches.
In the meantime, he will be leaving his motorbike where it is and instead using the bus or walking to and from town for work.