This was the moment a man riding an electric unicycle on a New Jersey road has to jump for cover after the machine bursts into flames on May 31.

Helmet cam footage shows a group of unicyclists manoeuvring in the road where one of the machines burst into flames.

The rider in question came off the machine with such vigour he broke his leg, while the electric unicycle veered towards a tree.

The filmer told Newsflare: "I usually go up to New York City to ride with the crew but this time I hosted the ride and we rode down the shore.

"The unicycle that caught fire had its original battery swapped out for a larger one by a third party seller.

"We think there was a short in one of the battery cells due to a faulty weld.

"My friend needed an ambulance because he broke his leg stepping off and twisting his knee.

"He then later announced his retirement from EUC[electric unicycle] riding.

"The fire was so violent because the battery was 3108wh or 31 times larger than what the TSA allows on an aeroplane."