Quote Originally Posted by smilingcat View Post
So there it was two sets of cogs just dangling on the skewer... It turns out he never rode in the smallest of cogs. The four lowest gears were fine. Top two was unusable in that state.
This reminds me of the time I was working on my bike outside, and one of neighbours comes along with a worried look and asks shyly if I can take a look at her son's bike, because "it doesn't work".

Apart from the flat, which I offered to help her fix a day I had a bit more time, it turns out that whoever had put the bike together - I'm assuming some bargain store - had just attached the derailleur cable at the shifter end, found out it was really really long, and instead of adjusting it to the right length and cutting off the slack had wrapped it around the frame until it was "short enough".

"Hey, he has a derailleur! He doesn't need to actually USE it!"