Ian Murray deliberately set alight the building at Bilston Glen Industrial Estate, Midlothian, destroying 15 motorbikes and causing damage of around £50,000,
Murray put two bikes on their side and left the fuel caps off before lighting the liquid and leaving the premises, in October 2017.
Smoke was seen pouring from the roof of the building of the specialist motorcycle business and firefighters attended soon after the alarm was sounded.
Officers who entered the building spotted two seats of fire on the upper level before using water to douse the flames and the police were called in to investigate.
Murray, 45, appeared on indictment at Edinburgh Sheriff Court on Wednesday where he admitted deliberately setting fire to his business.
A not guilty plea to attempting to embezzle £115,000 from Allianz insurance company and to embezzling £19,500 from two customers and providing a false statement to police were all accepted by the Crown.
Prosecutor Mark Keane told the court the industrial estate unit was the business of Ian Murray Motorcycles and the two-level property was “full of motorcycles” at the time of the blaze.
Mr Keane said the fire service was notified of smoke pouring from the roof of the building at about 7.30pm on October 22, 2017.
He said: “The fire brigade opened the wooden door at the front and found the fire on an upper level.
“An investigation was carried out and two motorcycles were found on their side with the fuel cap removed and this had been the cause of the fire.
“It had been deliberately set on fire with wood lying next to them [the bikes].”
The court was told Murray was alerted and attended his business at about 10.15pm. He said he had been at the unit earlier that evening and when he locked up everything was fine.
But after viewing CCTV police spotted Murray, of St Albans Road, Edinburgh, leaving and locking the business just two minutes before smoke was seen to come from the roof.
The two seats of fire were said to have come from a BMW and a Yamaha motorbikes which had been left on their side.
Murray subsequently contacted his insurance company and the estimated damage was said to around £50,000.
Defender solicitor Nigel Bruce said he would reserve all mitigation to the sentencing diet.
Sheriff Michael O’Grady QC deferred sentence for the preparation of reports to April 3.
Murray pleaded guilty to wilfully setting fire to a motorcycle whereby numerous bikes were damaged and the roof and walls of the building were damaged at Unit 5 Dryden Place, Bilston Glen Industrial Estate, Loanhead, Midlothian, on October 22, 2017.
Ian Murray Motorcycles was just one of two Royal Enfield franchises in Scotland and also sold Watsonian sidecars and second hand bikes.
The business also specialised in Ducati and operated as a satellite servicing centre main dealer Ducati Glasgow.
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