Jonathan Downes, a leading cryptid researcher, released the footage and believes the images could be genuine video of a creature unrecognised by science.
He is convinced the ape-like creature, with human features, could be lurking within southeast Asia, and should be designated as a new species.
Mr Downes, 59, has devoted his life to Cryptozoology, which is the search for evidence of creatures from folklore such as the Yeti, Bigfoot and The Loch Ness Monster.
Cryptids also aim to prove that some animals, that are known to be extinct, are in fact still alive in small numbers.
In the new video, the figure appears to sprint away down a track from a group of bikers.
They pursue the beast, but it again sprints off, and then disappears into undergrowth to the left of the track, Dailystar.co.uk reports.
According to legend, the Orang Pendek inhabit remote, mountainous forests on the island of Sumatra.
Orang Pendek directly translates to “short person” in Indonesian.
Sightings of the animal date back for more than 100 years.
Mr Downes said: “If I were going to put a probability on the existence of it – I would say 99 percent.
“We know so much about it.
“We’ve heard them, we’ve got footprints, and in 2009, two people actually saw one.”
He is the Director of the Centre of Fortean Zoology – an organisation dedicated to uncovering such sightings.
Founded in 1992, by Mr Downes, members of the group regularly attend expeditions in the hope of proving the genuineness of their claims.
He added: “There is no doubt in my mind that this animal exists and I think it is probably a fourth species of Orangutan.
“It is an ape-like animal that has evolved to be able to walk upright, rather than swing through trees.
“This is probably because several hundred years ago Sumatra – where these are found – was hit by an earthquake and the Orang Pendek very quickly evolved to walk upright instead.
The group have a YouTube channel, named CFZtv, who run a series called On The Track – providing updates on what they uncover during each adventure.