Originally Posted by creonte

Sounds seriously like you should get a road bike.

Originally Posted by a1penguin

If you want to get maximum speed gain, a road bike will give you more speed. Why? The riding position is more bent over and you have smaller profile and lower wind resistance. Road bike provide several hand positions and are more comfortable because you can change your riding position. Second, road bike generally have better and often narrower wheels. Road bikes are 23 or 25 mm wheels, while hybrids will often be 28mm or wider. And the wheel rims will be lighter and you need less energy to accelerate. The gearing on a mountain bike is very different that typical road bikes.

As you pointed out, hybrids are generally less expensive than road bikes. Perhaps you could put narrower slicks on your mountain bike and call it a day. I think that slicks on MTB should be comparable to hybrid, but a road bike might be faster. Do a few rides on your MTB, and then put some slicks on it and compare the speeds. If you think you are going to want a road bike in 6 months, a hybrid is a waste of money, unless you can find a used one that you could resell.

Originally Posted by pierce

for randonneuring (brevets), I'd be looking at a road bike like a surly long haul trucker something with longer wheel base relaxed geometry, and lugs to hold racks for the gear you need to travel with on long trips. the majority of modern road bikes are totally setup as race bikes, for speed in a peloton or time trial sprinting, and not as long distance bikes. one cue to look for at a road touring bike is how much room between the rear wheel and the seat tube, the race bike will have the bakc wheel right up against the seat post, while the touring frame will have 2-3 inches of clearance.. also a touring-oriented bike like the long haul trucker will let you mount a bigger tire, a lot of race oriented frames barely have room for a 25mm, and for randonneurring, you want a 28 or 32, but a /good/ one like a Continental Gatorskin, or a Vittoria Randonneur or Randonneur Hyper.

absolutely for sure get a proper fitting at the bike shop, find a fitter familiar with randonneur riding where you're riding for 2-3 days all day in a row, proper fit is critical.