Riding alone is no guarantee, my only really crash, 9/11/2012, riding alone mid afternoon and literally find myself sitting up on the asphalt, my R collarbone obviously trashed, helmet cracked, and when I tried to get up I couldn't, because my pelvis was fractured. No witnesses and to this day don't know what happened, wasn't going maybe 15 mph, no holes in the road, no dogs(at least that I remember). Worst damage was my beloved Look 585 had bent derailleur hanger which could not be fixed. Week in the hospital, lots of post concussive symptoms, collar bone repair, walker for 10 days, crutch for 2 weeks cane for 4 weeks, 10 weeks off the bike.