The new R1 sounds more like a big twin than an inline 4.
Example of how the bike sounds:
Link to original page on YouTube.
For comparison, here's an inline 4 without the cross-plane crankshaft:
Link to original page on YouTube.
Here's an explanation of how the engine works:
Link to original page on YouTube.
I hope that helps a little bit. It made sense to me, but since I couldn't find a similar video for an inline 4 without a cross-plane crankshaft, I'm a little fuzzy on the firing pattern of a typical inline 4.