They are by a company called puppetswar. I know these look a bit more like scout bikes than full space marine but it was interesting to see Sci-fi bikes with lances. These lances are bike mounted rather than carried in the hand which I would prefer but they do look quite cool!
I also found these more full marine bikes on their site.
These look really interesting and might make nice alternatives to spice up a bike heavy army, especially the heavy weapon one.