Some LBS guy is telling me that a tri bike is not a good buy because they can't handle curves and downhills.

Does this sound right to you all?

Broad sweeping generalizations like this one always set off alarms for me.
I've encountered downhills and downhill turns where I have briefly moved my hands from the aerobars to the brakes, but it's quite a stretch from this to an exaggeration like `can't handle downhills and turns.'

Ask Michael Rasmussen - he'd probably agree. But seriously, I don't understand why a salesperson would tell you that. Like Chris said, it's a broad generalization that may or may not apply to a particular rider. If a tri-bike were being purchased for a novice rider to be used on a highly technical course, then perhaps it's not the best bike choice. But my tri-bike (as well as several that I've owned or used extensively) can handle curves and downhills just fine.

I personally think that my Cervelo handles curves very well...almost as well as my roadie. With reference to downhills, I think that's pretty ridiculous. I've gone 45+ mph and felt rock solid.

I would say the biggest reason not to buy a tri bike is if you are planning to ride with people most of the time. The only time I ride my tri bike is when I am by myself because it can be unsafe to ride with others when you are in the aero position.

Thanks, that's what I thought. I'm not likely to do group rides, or at least close drafting rides.

I think the saleman was disturbed because I asked if there was such a thing as a tri bike with disc brakes. I don't know of any, so it looks like I'll have to give up on either disc brakes or a tri bike.

Years ago it might have been a little more true then it is today because of rule changes allows better geometry today. It is still a broad generalization as others have pointed out.

My 2005 tri bike takes turns and downhills great. I can take 90 degree turns at 30 mph and no problems holding a line doing 49 down the mountain at IMLP.

i wonder if the salesperson was referring to using areo bars? even if he was, he should have explained it a lot better.

I presume so. All the bikes I mentioned were like the P3 or Blade which either have or accept something like the HED aerobar. I don't see how one unit aero bar or clamp on aero bar would make any difference. You're still sticking way out front.