The header is blocking half the page, and the dropdown menus don't show what you can select (manufacturer, type, cc, etc.). Otherwise it's nicely done.

I'm not sure whether most of these are good learners. Especially the entire armada of barely road-legal enduros ;) Many bikes seem to be expensive classics (often with shocking handling, miserable brakes), or stuff for the really dedicated (e.g. the Dnepr, a SU/Ukrainian make that no longer exists, which will teach you more about motorcycle mechanics than you ever wanted to know).

So idk about the selection... are you targeting a specific part of the world?