You should read up they changed the rules to make everyone ride on a standard bike like Mercyc did in 73???so you knew it was about the rider and not the bike. Ther eis the UCI record and the Best Human effort
It is on the documentary of boardmans attempt about how they had to get the drag value to the same as mercyx’s attempt as well and they had issues with the helmet iirc
in essence there was a hoopla it is just that you dont know about it [ no offence trying to politely give info]
In 1993 and 1994, Graeme Obree, a Scot who built his own bikes, posted two records with his hands tucked under his chest. In 1996, Boardman set a record using another position pioneered by Obree, his arms out in front in a Superman position. Both were considered controversial by the UCI, and while the records were allowed to stand, the positions were banned. Obree and Boardman made several attempts to top the previous record.
With the increasing gap between modern bicycles and what was available at the time of Merckx’s record, the UCI established two records:
the UCI Hour Record (which restricts competitors to roughly the same equipment as Merckx, disallowing time trial helmets, disc or tri-spoke wheels, aerodynamic bars and monocoque frames) and
the Best Human Effort – sometimes termed the UCI “Absolute” Record.
All records since 1972, including Boardman’s 56.375 km (35.030 mi) in 1996 were downgraded to Best Human Effort. In 2000, Boardman attempted the UCI record on a traditional bike, and rode 49.441 km (30.721 mi), topping Merckx by 10 m (32.8 ft) – an improvement of 0.02%.
In 2005 Ond?ej Sosenka improved Boardman’s performance at 49.700 km (30.882 mi) using a 54×13 gear. At 200 cm (6 ft 6¾ in) tall, Sosenka used an unusual saddle position and a small vertical frame height to stay within UCI regulations.[2] Sosenka failed a doping control in 2001 and then again in 2008, the latter resulting in a career ending in suspension which puts in doubt the validity of his record