Quite reguarly we get bikes through our workshop which are brand new but have been bought on the internet and not properly serviced. This week we had a nice carbon MEKK in the workshop which the customer complained their was a knocking noise from the bottom bracket. Once we stripped it down it was obvious that the noise was due to the left hand bottom bracket cup being loose. Although we greased the bottom bracket threads just for 
good measure. Hey presto! No more noise! But this is a something that should be sorted out under warranty from where the bike was originally purchased. However if that is at the other end of the country you’ll probably just end up doing what this customer did, which was pay his local bike shop to fix it.
Next up is a brand new Specialized Tarmac Expert DI2. With 2 small issues which can be quickly resolved by a good bike shop but if the bike was bought on the internet and arrived in a box on your doorstep could quickly turn into a nightmare.
Firstly this bike came with a small scratch on the DI2 brake lever. Now when a bike costs this much, you would be right to expect it to be free from scratches and marks, so we replaced the lever straightaway. Job done. But imagine trying to convince an online retailer that the brake lever is scratched and it was like that when you took it out of the box and built it up yourself?
This bike has internally routed brake cables in the top tube. To make it easier to thread the cable through, the rear cable opening is bigger with an alloy cap held in place by a tiny M3 allen screw. Now usually the screw will screw in no problem, but on this bike the screw threads were a little bit burred at the end so the screw wouldn’t go in straight. Not a problem for us to sort that one out, but it is very easy to try and force the screw in especially when you want to get riding your new bike. Before you know it you’ve one very expensive damaged frame.