John McGuinness achieved his second win at the 2004 TT Races

McGuinness, now on five TT victories overall, won the 400cc race ahead of Steve Lindsell and Mark Parrott to add to his win in Saturday's Formula One.

There was a home winner in the 125 race with Chris Palmer from the Isle of Man winning and Northern Ireland's Robert Dunlop taking second place.

Monday races had been held up because of fog on the mountain course.

The Production race scheduled for Monday was postponed until Tuesday because of the delay.

Runner-up in the 125, Robert Dunlop, said Monday's race was probably his last on the Isle of Man as he was considering retiring at the end of the Northern Ireland road racing season.

"I am disappointed not to have won but my first lap was not good," said the brother of legendary TT record holder Joey Dunlop.

"But I am satisfied to have survived the Isle of Man and getting a podium finish."