The organisers of a two-wheeled world land speed record attempt by motorcycle racer Guy Martin have said runs will be delayed for a short time while they wait for "absolute perfection" on the course.
Martin, 34, from Grimsby, North East Lincolnshire, was due to begin record runs on the 11-mile course on the Bonneville Salt Flats, in Utah, USA, earlier but attempts have been delayed while the salt dries out.
Triumph Motorcycles have said the conditions of the course must be perfect before the attempt is carried out.
A spokesman for the company said: "There's no motorcycles running this morning while we wait for the course. We're hoping to see some cars go out round about noon and that will give us a chance to look at the course.
"There's some dampness at the top end and setting the land speed record we need the absolute perfect conditions.
"It's a great salt course, it's the best it's been in years, we're just waiting for absolute perfection, we're just waiting for that last little bit of perfection.
"We're hoping to see movement on the track soon, then we'll be out as soon as we can be."
Martin will ride the purpose-built 400mph Triumph Infor Rocket Streamliner as he attempts to break the current record of 376.36mph.
During practice sessions over the summer, the bike became the fastest to be built by Triumph as the TT star achieved a speed of 274.2mph.
The bike was designed by aerodynamic engineer Matt Markstaller.
It features a carbon Kevlar monocoque construction - in which the chassis is integral with the body - with two turbo-charged Triumph Rocket III engines producing a combined 1,000 brake horsepower (bhp) at 9,000 revs per minute (rpm).
The bike is 25.5ft long, 2ft wide and 3ft tall and is powered by methanol fuel.
Martin said: "The Triumph engineers have built an amazing machine, giving us the very best chance to beat the two-wheeled land speed record."
Martin has set speed records in a variety of human and engine-powered vehicles, including world records for fastest speed on a gravity-powered snow sled, fastest speed in a soap box and highest speed on a wall of death, which he set earlier this year.
The current motorcycle land speed world record was set by Rocky Robinson in 2010, riding the Top Oil-Ack Attack Streamliner at 376.36mph.