FARES on the Mass Transit Railway will go up by an average of 7.1 per cent on May 1, the Executive Council agreed yesterday, and more commuters will pay less if they travel before or after the crowded morning rush hour. But the fare rise looks likely to receive a stormy reception. United Democrat transport spokesman Lau Chin-shek called for a price freeze, saying the increase was inflationary and unnecessary. From May 1, the MTR will remove the 80 cent discount for travelling through the Eastern Harbour Crossing between 8 am to 9 am because of the increasingly large crowds piling up at Quarry Bay station, pushing that station close to its safety limits. The change will mean it will cost the same to travel to work across the harbour on either the Tsuen Wan line or the Kwun Tong line. The 80 cent discount for travelling down the Nathan road corridor before 8 am or between 9 am and 9.30 am is set to be extended. The aim is to encourage people to change their travel habits so that the MTR can cope during peak hours. Commuters from four more stations - Lam Tin, Kwun Tong, Ngau Tau Kok and Kowloon Bay - will be added to the discount travel zone so people setting out for work from any station in Kowloon to travel into the business district will get a reduced fare. The average increase is below last year's inflation rate of 8.5 per cent and below the 12.9 per cent rise granted to Kowloon Motor Bus last week, but the MTR is not expecting a big switch to the MTR even though the price difference with bus fares will begreater than last year. This year's fare rise will be scrutinised even more carefully by the public and legislators after the Kowloon Canton Railway announced last month it had made so much profit it was freezing fares for a year as a gesture to its customers. Mr Lau was quick to condemn the MTR's fare increase. He said the MTR's profits had risen by 82 per cent last year from $403 million in 1992 to $735 million in 1993, while the corporation had only forecast a modest rise to $461 million. ''It has the ability and indeed the responsibility to freeze its fares,'' Mr Lau said. ''What saddens me is the MTR has in its habitual manner put fares up in line with inflation without any regard to people's livelihood,'' Mr Lau said. Mr Lau also opposed the lifting of the Eastern Harbour Crossing discount, saying the MTR had encouraged people to change the way they travelled and them left them high and dry. He repeated his call for the MTR Ordinance to be changed so that the Legislative Council had the power of veto over MTR fare increases.