Join Date: Jun 2002
Location: Central Illinois
Bikes: Colnago CX, Giant Propel, Spec. Roubaix Pro, Co-Motion Supremo
You fall over sideways. I've ridden zillions of miles on rollers and can verify that even at 60 mph, you just fall over sideways if your bike goes off the rollers.
My racing team used to ride rollers in a local mall for charity events and a rider would sprint to 60 mph for a $1.00. It's not very hard to spin that high for a couple of seconds. Anyway, every now and then as the day wore on and every one was getting tired, someone would invariably fall off in the middle of a sprint. The bike would go about 3 inches. It does burn the carpet, though.