Already-thick traffic quickly jammed up after the pileup around 5:15 p.m. in the right local lane of what's known as Christopher Columbus Highway just before the exit for Rochelle Park and Riverview Avenue.
Neither riders sustained life-threatening injuries, responders said.
Moments before the crash, a driver reported the two "cutting in and out and riding between the lanes.
"I’m thinking 'How dangerous...," he said. "A few minutes later I’m passing the same two guys -- but they were on the ground."
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