lousy warranty

After one year my 1200 watt generator only produced 150 volt power. It was supposed to have a 2 year warranty. I brought the generator to Stevens & Co in Montague Gardens Cape Town. After a week I got a quote of 450 rand for the repair although it was still under warranty. The gentleman on the phone said that the voltage regulator did not fall under the warranty. Why the F... not? SO Ryobi warranty is very questionable in addition the relative poor quality compared to other brands.