Bajaj Auto on Tuesday reported a 35% year-on-year (YoY) rise in profit after tax for the September quarter at Rs 3,354 crore, as strong demand across its domestic and export businesses helped the two-wheeler maker post its highest-ever quarterly revenue.Revenue grew 34% YoY to Rs 20,003 crore for the first time, doubling over the past three years. The company also reported EBITDA exceeding Rs 4,000 crore, a rise of over 37% from the year-ago period.Operating margins remained steady at 20.9% despite higher input costs and volatile commodity prices.