How I read it is that it means is that each item of sporting gear requires 1 piece allowance

If having 1 piece allowance, then a bike will use it up

if travelling with, say, skis and a snowboard, then will need 2 pieces allowance ( 1 for the skis and 1 for the snowboard )

i.e you will need to ensure that you have purchased an allowance such that you have enough for the total number of pieces you plan to check in and that there is no extra allowance for golf clubs etc

If you have an appropriately packed bike that is within weight and size limits and within your baggage allowance , then should have nothing to pay