'There were audible gasps' – is this the unbreakable record?

As community buildings go, Hirwaun village hall, in South Wales (UK), is nothing special. Its modern and inoffensive brick exterior, complete with solar panels on the roof, sits within the perimeter of a slightly forbidding galvanised steel fence.

The hall hosts the usual variety of community goings-on. Short-mat bowls on Mondays are followed on Tuesdays by a Welsh-language craft club, while Thursdays see practical sewing and Weight Watchers.

Weekends in Hirwaun are set aside for "birthday parties and events" – and it was at one such event, here at this innocuous little venue in early May 2018, where one of the greatest time trial performances in history was announced to the world.

The event in question was the Welsh CA Championship 25, which fell in early summer, the season only just beginning to swing and the weather as yet so-so.

Remembering the post-race scene, event organiser Martyn Heritage-Owen tells me that only a few cars were left in the hall's small car park at the rear and a smattering of riders left inside as he received news of the momentous result.

"I was getting WhatsApp messages from [timekeeper] Robin Field at the finish," says Heritage-Owen. "I'd been filling in my spreadsheet for the CTT [Cycling Time Trials] website later that day and writing them up on the results board. There was a small crowd of people that had stayed on round the result board and I deliberately wrote everybody's time up, other than the winner's." 

His delaying strategy having heightened anticipation, the race organiser finally wrote up the winner’s time. "There were audible gasps,” Heritage-Owen recalls. “From a room that had been relatively quiet, it suddenly got quite animated."

The time was 42.58, ridden by Somerset-based Pole, Marcin Białobłocki – beating his own previous record by 1.06. The record before that was Alex Dowsett's 44.29, meaning that Białobłocki had now gone 1.31 faster than anybody else for the distance. Białobłocki's average speed on the day was a blistering 34.91mph (56.18kph) – a respectable enough top speed to achieve on a descent, let alone to average on the flat for nearly three-quarters of an hour.

Aged 34 at the time, the Polish rider had not long stepped down from the ProConti ranks – three years earlier, in 2015, he had won the Polish national champs TT as well as a stage of the Tour of Poland.

There was no questioning his pedigree. His ‘25’ record has stood for more than five years now, with few riders getting anywhere near it. What's more, time trialling is suffering a slow drip of lost courses, as roads become busier, or new interchanges pop up.

The Glynneath course where Białobłocki went so outrageously fast – officially listed as R25/3H and well known in time trial circles as being one of, if not the fastest '25' course in existence – is currently out of action due to roadworks, not expected to return until 2025.

It all leads to the inevitable question: is Białobłocki's record literally unbreakable? A glance at his Strava file for the activity shows a thigh-busting average weighted power of 429 watts – impressive even for a man of Białobłocki's 6ft 4in (193cm), 80kg frame.

And what made his ride all the more impressive was the fact that this was no 'float' day – those perfect conditions that are a time trialling holy grail and may only occur once every year or two for any one rider.

"It wasn't a great day," says Heritage-Owen. "I seem to remember it was sunny, but the conditions weren't ideal, being an early-season event."

Aerodynamics guru Dr Xavier Disley was working with Białobłocki at the time of the record, having developed some of the equipment the Pole was using that season. Disley tells me how Białobłocki's reserved nature meant he was a bit of a dark horse for many.

"He knew his stuff, way more than people really realised," says the aerodynamicist. "He was very considered in his equipment choices and he was doing his own aero testing. But I don't think anyone really realised it because, you know, he wasn't shouting about it."

Disley describes Białobłocki's ride as "pretty remarkable", but nevertheless believes it to be beatable. "Not just from an 'all records can be beaten' perspective," Disley clarifies. "If you break down the numbers, then yeah, someone could have it. You'd need to be very, very good, and obviously we know of a certain British-born time triallist who is exceptionally good these days," he adds, in a less-than-oblique reference to Josh Tarling – the 19-year-old Ineos Grenadiers rider who claimed a World Championship time trial bronze medal in September, his first outing in the senior event.

Cycling Weekly columnist Michael Hutchinson – a former 25-mile comp record holder himself – agrees wholeheartedly with Disley's view. "The thing is, there are riders around with the power and the CdA who could do it – on the right day, on the right course," Hutchinson says. "I think Josh Tarling could certainly do it. Guys like John Archibald could do it on the right day, on the right course. If young [Alex] Dowsett got his act together next year, he would be in a shout of getting it, on the right course, on the right day," he continues.

The bigger question, Hutchinson points out, might be whether a rider of the right calibre is likely to turn up at the right event, on the right day.

"If you take it to one extreme, you could say Remco Evenepoel wouldn't have too much trouble with it. But he's never going to do it. With Josh Tarling, who maybe does it [a 25-mile TT] in two years, does that work? I mean, I broke the 25 record, but it took me quite a lot of 25s to get there," he adds.

The other major issue – and one which could one day become the biggest stumbling block when it comes to breaking comp records – is course availability. The 'right' course is key, as Hutchinson has emphasised, but there are only a few.

The 'right' course – for 'right' read 'fastest' – has a few key ingredients: plenty of traffic to help drag the rider along (but not so much it's dangerous); few roundabouts; and as flat a profile as possible.

The Glynneath course where Białobłocki set his record features a 'gift' hill – one that you get to ride down but don't need to ride back up. Białobłocki reached 55mph on this descent, according to Strava, although Hutchinson is happy to put that in the shade with the 70mph he reached with Sean Yates in one event they rode on the tandem on that course. In short, it's a very quick course – but it's also one that is currently out of action.

For speed, it has few rivals. Off the cuff, Disley lists them: "You've got the E2/25 [near Cambridge], you've got the A25/11 [Etwall course, near Derby]... and there's the J5/8, which has a quick start to it. That might work, and there's the P883 near Guildford. That's pretty good."

Try not to feel bamboozled by the time trialling course code speak. Instead focus on the fact that, out of the scores and scores of 25-mile courses in Britain, there are only four that might witness a successful record attempt.

Also pertinent is the fact there were five – roadworks stopping play is a common theme in time trialling. Courses are slowly being lost, ruled out by traffic lights springing up, or excessive traffic levels making them unusable, or new housing and business developments seeing them re-engineered.

Were there many more than four courses with record potential in the sport’s golden days? "I think it's always been that kind of number," qualifies Disley, "but it's just when you take out the top couple, you jump down to the next rung – you lose a few minutes here and there."

Courses have been disappearing throughout his career, Hutchinson says, but new ones have been created too – he points out that the very fast aforementioned E2/25 did not exist when he began racing.

"Fast courses have always come and gone," he adds. Hutchinson echoes Disley's view that no record is safe on the shelf forever: "If the [Glynneath] course is back in action in 2025 I would expect somebody either to break it or get close enough to it to make it perfectly clear that breaking it was feasible."

SIMMONDS'S SIZZLER

The closest we have to a truly unbreakable record may be Hayley Simmonds's 10-mile record – 18.36 – which is eight years’ old this summer, having been set back in 2016 on the now-defunct V718 course at South Cave near Hull.

Xavier Disley puts the achievement into context: "Her record is obscene, and with the death of the V718, yes, obviously someone can beat it – because all records can be beaten – but no one's got close. It would be a decent ride for someone to take it any time soon."

Simmonds, who is riding for the Doltcini O'Shea team in 2024, went 32 seconds faster than previous holder Anna Turvey when she took the record, and since then only two riders have got within a minute of her and no one has beaten 19 minutes – huge margins over such a distance.

"I think that will be one of the ones that really stands the test of time until we see another step change," adds Disley.