It's probably not surprising to learn someone known colloquially as Rhino considers the keirin his favourite event "because it's so lawless''.
It's a fascinating event that sees multiple track cyclists follow a motorised pacer until the final 600m when nerve is as much of an asset as power. Or the bullishness of a rhino.
Simon van Velthooven won bronze in the keirin at the 2012 Olympics, a medal he shared with Teun Mulder of the Netherlands when the two couldn't be separated, and famously invited New Zealand to a party at his house to celebrate.
The 25-year-old will be among the favourites in both the keirin and kilo time trial at the track cycling world championships in Colombia that start tomorrow morning (Thurs NZT). He won silver in the time trial at last year's world championships in Minsk and comes into the event in good form after finishing third in the World Cup rankings.
France's Francois Pervis, who recently broke the world record in the kilo time (56.303 seconds) and is current world champion, will be tough to beat but van Velthooven is predicting good times in Cali.
The track is covered but doesn't have walls which means the elements could play a significant part (it was flooded earlier this week). It also has tight corners and long straights so the potential for crashes is higher.
That risk is part of what van Velthooven enjoys. He likes the time trial (``the kilo is measurable so it tells me where I am at against the best in the world,'' he said) but it's the keirin that excites.
"The keirin is my favourite event because it's so lawless and anything can happen. It's the person with the most grit who does well.''
Van Velthooven learned that when competing in the professional keirin racing league in Japan - a sport that sees huge sums bet on riders competing on heavy, steel bikes and decked out in padded outfits to help protect them when the inevitable crash happens.
It's been lucrative for van Velthooven but he won't look to renew his contract after the upcoming season as he looks to focus on the 2016 Rio Olympics.
Van Velthooven wants back in the New Zealand's team sprint side - Eddie Dawkins, Sam Webster and Ethan Mitchell rode the event in London.
"With my contract in Japan, I can't do heavy lifting in the gym and long blocks of training that specialise on starts,'' he said. ``Starting is one of my downfalls as a sprinter. I am shooting myself in the foot by racing in Japan. From September onwards, I will be fully focused on the team sprint, and keirin as a hobby.''
It will be a little more than that. The keirin will still be on the Olympic programme in Rio and the retirement of Sir Chris Hoy, who won the keirin to claim his sixth Olympic gold overall, has opened things up a little.
Van Velthooven shared a beer with Hoy in a London nightclub after winning his bronze when Hoy offered to be a sounding board if he needed some advice.
"He won his first Olympic medal when he was 24 so he told me to keep at it,'' van Velthooven said. "Everyone says good things take time and it's very true. If you train hard and keep your head down, your turn will come.''
New Zealand will field a 10-strong team in Cali, with Aaron Gate defending champion in the six-event omnium.