I love the skeletons on motorcycles and the Frankenstein's Monster with the chainsaw arm.
I mean, sure, there weren't motorcycles in the mid 19th century, and they wouldn't even come around until about 50 years later--and ones of the caliber seen in CV64 and LOD wouldn't appear until another 20 or 30 years or so--but I don't really care. It's goofy, and I love it. :)
It always made more sense to me for CV64/LOD to take place around WWII.
Speaking of which, when are they gonna make a Castlevania game where the Belmonts slay Nazis? Maybe even Nazi vampires, but then that would be getting into Hellsing territory. But hey, why not? Pay homage to that great manga. Hellsing has a couple chapters titled "Castle vania", so go for it, I say.