Originally Posted by
baribari
No, it isn't... you have to get new brakes, shifters, and cables, and that's only if your crank, rear cassette, chain, and hub are compatible...
A lot of flat-bar bikes are essentially just mountain bikes with road wheels... even down to the drive train.
You're wrong about this. There are plenty of flatbar shifters and brake levers compatible with road components - I know because I've built several bikes like that.
If you buy or build a ROAD BIKE WITH FLATBARS all you need to switch to drop bars is bars, brifters, and new cables if the old ones are too short. Maybe a new stem and a couple of spacers if you want to raise the bars. That's all.
If you buy a MOUNTAIN BIKE or some of that hybrid crap, then you're not going to change it over. But we're not talking mountain bikes, we're talking road bikes.