Today, for the first time ever, I got inside an STI shifter. A flat bar one, so it's pretty simple; in fact it's only integrated in that it's in one housing with the brake lever, so hardly deserving of the name. After a new cable, cassette, chain and some tinkering, the gears are no longer clinking and clunking. More to the point, the chain's not skipping either. Seems like I probably could have done without the new cassette, it just needed a new chain – the old one was the factory original, I think, which means it was about six years old(!) (but had been in storage for a couple of years) so no complaints. And now I've got a quick link. Why Shimano persist in fitting chains without them, I don't know. And closer ratios, which may or may not be noticed in practice.