When I lived in S California we would see these critters on occasion sunny themselves on mountain roads, going up we gave them a wide berth but coming down doing over 45mph we simply ran them over because it was safer to that then to try to swerve. I don't think the bikes would kill them but they didn't like it either because you would here their rattles shaking. First time I experienced I pulled my feet out of the pedals and held them up as high as I could, later I found out we were going to fast for them to strike us.