Jason Richards, 40, who is understood to be from Rogerstone, was riding home from a bar in Kamala, on the holiday island of Phuket, when the accident happened in the early hours of Wednesday.
Just weeks earlier Mr Richards comforted the family of his school friend, Newport Royal Marine Steven Thomas, who was left fighting for his life after being involved in a separate scooter accident elsewhere on the island in September.
Mr Thomas, 39, is now recovering well at Newport’s Royal Gwent Hospital, and his stepfather Allan Gardiner said the family were shocked and saddened by the news of Mr Richards’ death.
He said: “He was a great support to us. He was Steven’s mate and came to the hospital to try to chivvy him up. It’s just really sad.”
Mr Gardiner said the former Bassaleg School pupils were close and his step-son acted as Mr Richards’ protector as he recovered from a serious accident aged 14, which landed him in a coma.
Tributes and message of support have have flooded in via a Facebook group set up to support Mr Thomas after his accident.
They include one from Angie McCulley, secretary of the Royal Marines Association Phuket, who met Mr Richards when he visited Mr Thomas.
She wrote: “Was only talking to Jason in our local Tesco (he lived in the same village as me) on Monday and he was saying how happy he was here in Kamala and life couldn’t be any better for him.
“He was saying how he wanted to go back next year to visit Steven and couldn’t wait for Steven to be fit enough to travel back out here. Such a lovely young man with a heart of gold. Very sad RIP Jason.”
A friend, Katie Wellington, wrote: “I have had the pleasure of meeting two of the most loveable guys here in Phuket – one now is rebuilding his life back in Wales and the other will be taken back home to eternal rest – both will remain with fondest memories in my heart.”
Thai newspaper Phuket News reported Mr Richards had been living in Udon Thani, in Thailand’s north-east, for the past three years.
He only went to Phuket when he learned of Mr Thomas’ accident after reading it in the news and decided to start a new life there.
A Foreign and Commonwealth Office spokesman said it had been informed of the death of a British national in Phuket on November 23, and were providing assistance to the family.