Hmm... weird.
It does sound like bones clattering, so it's appropriate, I guess. It doesn't really bother me, since it's quiet. Speaking of, anyone think the voices are unnaturally loud? You're under a bridge, in a go-kart with a motor, a character in another go-kart with another motor that's only kind of close to you, and you can still hear them. That's not really annoying at all, I just think it's barely possible.