Dunlop died on Thursday evening following an accident during a practice session for Saturday's North West 200 250cc race.
It's believed his bike seized while the Ballymoney rider was approaching Mather's Cross at 160mph, flinging him over the handlebars of his TSR Honda.
"This was an accident which appears at the present time to be machine failure," said Clark of the Course Mervyn White.
"It could have happened anywhere at all, it could have happened on the open road."
Sports Minister Edwin Poots said, "Robert was a much loved respected and talented member of the motorsport community and will be missed by all.
And Liam Beckett, the former Institute FC manager who was Dunlop's long-time mechanic and a close friend, said "I don't know of a more caring and devoted father - he just lived for his family.
"They are a unique and resilient family, and to be honest they were in pieces last night."
He is survived by wife Louise and sons Michael, William and Daniel.
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