Alexander Freer's 50cc motorbike was struck by a van in Glasgow's South Side as he went to a grocery store in the middle of the afternoon. He was thrown off his silver and black moped by the impact.
Passers-by rushed to help him and dialled 999.
He was taken to the Victoria Infirmary and was found to have a broken pelvis and injuries to his face and hands.
Police are trying to trace the driver of the white Ford Escort van, which failed to stop.
Mr Freer, from Toryglen, said: "It is upsetting to think someone would just drive off."
The accident happened in Pollokshaws Road at its junction with Kilmarnock Road, next to the Granary pub, in Shawlands on Friday at 1.30pm.
Police are studying CCTV footage and have asked any witnesses to contact them.
Mr Freer said: "I was on my way to Thornliebank because I do my shopping there.
"I was just approaching the pedestrian crossing. I was doing only about 15mph and got an awful smash on the side from a white van.
"He was in the outside lane. I never saw or heard him. I was thrown off my bike. I saw the van disappear and, next thing I knew, people were round me.
"I broke my pelvis and I am covered in cuts and bruises. I am sore all over. There isn't anything doctors can do for a broken pelvis.
"The driver must have seen me because it was an awful bump. It is quite upsetting someone would drive off."
Mr Freer was a van driver before he retired and would go out two or three times a week on his moped for shopping.
But Mr Freer, who has a 102-year-old sister Helen, said he was now too frightened to go back out on his moped.
He said: "I have been driving cars and bikes for 55 years, but I don't think I will be driving any more. I will just take the bus."
Constable James Todd, of Cathcart police office, is appealing for witnesses. He said: "This is a busy junction and there would have been lots of people about who would have seen what happened.
"We are checking CCTV from the businesses nearby, but would appeal to anyone who was in the area or who saw the crash to contact us."
Anyone with information can call Cathcart police office on 0141 532 4900 or Crimestoppers on 0800 555111, where details can be given in confidence.