Didnt expect that you watched it! And yeah, its a bit sad that they initially had a so much better scene in the rain that double diped as to be how the scene in the manga that is based on played. But it was too dangerous to use motorcycles on the wet dirt and probably they didnt feel that using CGI for the rain would be auntethic enough.
the shocker riders fight was a little too dark though i will agree with that (though i'll say this much i think the imagery of the first shocker rider being set alight with the flames visible through their helmet's lenses goes way too hard to only be seen for a split second)