On this page we attempt to make available the experience of individual bicycle tourists who have travelled with Jetstar (you can share your experiences here).
Jetstar vs Virgin Blue (Australia) Excess Baggage for Bikes
Having just participated in the Great Tasmanian Bike Ride, we've been able to compare the airline policies and charges for carrying bicycles. Jetstar charges AUD$5 per kilo for EVERY kg of excess over 20kg, with no special allowance for bikes; and no negotiation.
By contrast, Virgin Blue will only count a bike as 5kg of the total allowance, regardless of what it weights, and their excess baggage charges are less, and they were known to waive it for some people. Based on that I know who I will be flying with next time!