He dismisses the notion of risks as no greater than normal boxing because of the shorter rounds, taking less punches over a shorter timeframe, and gloves doing more to protect hands than heads.
But the smaller ring space is just another factor why there are more fights ended by knockout or technical knockout than standard boxing, not to mention a greater risk of cuts. A concern for some, an appeal to others.
“It’s stripped back, the truest form of fighting,” he says. “And I’ve got something to prove.”
Put to him that holding a world title suggests he doesn’t, he replies: “Yeah, but I had pillows on my hands.”
He’s yet to try and pillow-less punch on an opponent but says pad work suggests his punches are “so much faster, so much cleaner”.
He’s yet, either, to receive a bareknuckle punch and admits his sister worries. His father – who he calls “a boxing purist” – wants nothing to do with the venture.
But brother and fellow boxer, 2012 Olympian Andrew Selby, has joined him in making the switch into the three-sided ring known as the Trigon.
“I’ve had huge success as an amateur and won the British title in the pros. Now, joining my brother Lee in BKB is a dream,” said Andrew.
“Bare knuckle is the original, no-excuses version of the sport we love. I’m bringing my speed, timing, and heart to the Trigon – and we’re both coming for world titles.”
Lee Selby’s only live experience of it to date has been coaching one previous fight but he’s been studying and notes that the venue sizes are growing.
And just as he knows the risks, Selby is equally clear on his aim.
“The plan is my debut which I don’t want to look past,” he says. “But, if I was to look ahead, I’d like another fight and then to fight for the world title, defend it and retire a two-time world champion.
“World champion with and without the gloves and the best fighting man from Wales.”