I have created an online shop for bikes. They do not have an offline (brick & mortal) shop.
Can I use the Schema.org type
Bikestore (e.g. in Microdata:
itemscope itemtype="http://schema.org/Bikestore") or is it just for local businesses?
https://schema.org/BikeStore (with a capital S) is defined in the following hierarchies:
Thing > Place > LocalBusiness > Store > BikeStore
Thing > Organization > LocalBusiness > Store > BikeStore
The definition of
A particular physical business or branch of an organization. Examples of LocalBusiness include a restaurant, a particular branch of a restaurant chain, a branch of a bank, a medical practice, a club, a bowling alley, etc.
So, no, it would not be appropriate to use that particular
itemtype for an online-only store.
Other Microsoft data from schema.org might be appropriate though.