Nope, unfortunately you can not. 

The bike stations at Lysaker and Fornebu appear similar to the ones in Oslo, but the bike system belongs to the Municipality of Bærum. It is not possible to park or unlock a bike from these bike stations.

Stations

You can see the stations you can use as an Oslo City biker in the app and the map on our webpage.

If a bike is parked at a station that belongs to Bærum, it must be picked up by the operating crew from Bærum. This takes a lot of time from us and them, in addition to making the bike unavailable to other city bikers, so we kindly ask you not to do that. If you already have parked a bike in one of their stations we ask you to contact Bærum city bike, they can help you retrieve it. Their contact info can be found here