Last year, on my 10 mile commute to work I was unlucky enough to get a double blow out after hitting a pot hole, at speed, in traffic. I pushed it to a bike shop (Cycle surgery, West Hampstead) for them to repair while I continued to work on public transport - 2 buses there then 2 buses back to the shop to collect my bike and get home. I was shocked that 2 inner tubes (£5 each) and fitting cost me £26 total. £8 per wheel to change an inner tube! I want to support bike shops but this is believe to be taking the piss.