After an apprenticeship on short circuits, the teenage Dunlop made his road race debut at the 1979 Temple 100.

Riding an ECM, he averaged 88.57 mph to take the chequered flag ahead of Gary Cowan (EMC) and Noel Hudson (Rotax).

Dunlop notched a double in Ireland's North West 200 and finished third in the F1 Isle of Man TT.

[3] In 1994, Dunlop suffered a major accident on the Isle of Man Formula One TT, when the back wheel of his 750 cm3 Honda RC45 collapsed in a long left turn, just after he took the jump over Ballaugh Bridge.

Many believed that Dunlop's racing career was over, and he was left with severe tendon damage which restricted movement, and a shortened leg from the accident.

Dunlop chose the Cookstown 100 on 20 April 1996, and although still not fully fit, took ninth place in the 125 cm3 race won by brother Joey.

Subject to severe insurance restrictions and costs due to his continual pain and deteriorating condition of his leg, and even questions in the Northern Ireland Assembly,[4] on 16 December 2003 Dunlop announced that he would quit motorcycle racing after the 2004 season.

Dunlop announced that he was hoping to win the Isle of Man TT and North West 200 before he quit, and that he intended to focus on his sons, William and Michael, and pass his motorcycling experience to them.

At the event, Dunlop announced that he was shortly to enter hospital to have his injured leg broken and lengthened, an inevitable conclusion to his 1994 Isle of Man TT accident.

In February 2006, it was announced that Dunlop and his brother Joey were honoured with Honorary Degrees from the University of Ulster, in light of their achievements in the field of motorcycle racing.

On 15 May 2008, Dunlop died after suffering severe chest injuries in a crash during a practice session at the North West 200.