The Yamaha YBR125 is a great learner bike or commuter bike for anybody. But with winter use the the standard exhaust will rot very quickly. There are plenty of cheap mild steel versions available from China that can be bought from ebay for around £100.00 but they won't last even as long as the original. They are in many cases utter rubbish. The GPR stainless system will last and last.
Yamaha YBR125 stainless exhaust system