Any difference between a TT and Tri bike?
 

Any major difference between a TT and Tri bike? Some brands seem geared more toward TT's (Trek TTX), and other seem to focus on the Tri market (Quintana Roo). Any thoughts on selecting a TT bike?

while they're often interchangeable, a true TT bike will not be as comfortable for a longer triathlon. The position the top TT'ers ride is great for what they do, and will work fine in a sprint or olympic distance tri, but when you get into longer tris comfort comes in to play.

TT bikes generally have a more aggressive position ie with handlebars further down
this is because if you stiffen up your back by riding in a more aggressive position in the bike part the transition to running will be much harder, slower and less smooth
TT:
http://www.roadbikeaction.com/imagef...bikeaction.jpg
TRI:
http://www.getactivetampa.com/Bike.jpg

Tri bikes don't have to comply with UCI regs. One of the more noteable one's regards the positioning of the front of the saddle in relation to the bottom bracket.

Also a bike optimized for triathlon takes into consideration the fact that you have to run when you get off the bike.

Without the constraints of UCI regs, the seat can be further forward, and a steeper seat tube angle, making it easier to run when you get off the bike leg.

However, unless you're looking at the definition of a UCI legal TT bike, there really is no clear distinction between a TT and a Tri bike.

Tons of triatheletes for example ride Cervelo P3's, which is also used in many TT's.

The bike I TT on, a Griffen Vulcan, was marketed mostly to the triathlon crowd, but it certainly used by people in TT's.

Incorrect.

This is because Tom Boonen has a better aero position than some recreation triathlete in Tampa.

Take a look at Mark Allen.

http://bleacherreport.com/images_roo...play_image.jpg

Also, in theory the seat angles are slightly different so you can come off the bike a little fresher on the running muscles. I know the Colnago Flight is sold with two seatposts, to put you at two different angles for either a TT (74 degree seat angle) or Tri (77 degree) fit.

http://www.colnago.com/flightENG.html

^ the 74 degree seat angle is going to facilitate a UCI legal set up. The 77 degree is going to open up your hip angle a bit, facilitating the run transition.

They're the same bikes. The difference is how they can be set up. Look at guys like Sindballe or Macca or Normann.....all very aggressive, probably close to a pro cyclist.

Age groupers tend to be a little more comfort oriented, because, well....they're not super human like the pros are.

Same bike... potentially different setup... I love how the pic of Boonen on a TRANSITION is used as an example of a "TT bike". The name Transition comes from triathlons.

Again with the UCI/non-UCI differences, but since Tri bikes don't have to conform, there are a lot more possible frame combinations.

A Kestrel Airfoil
http://i572.photobucket.com/albums/s...l-pro-se-1.jpg

A Softride
http://i572.photobucket.com/albums/s...img1_large.jpg

Plenty of pro triathletes and some age-groupers ride their bikes in very, very good aero positions:
Torbjorn Sindballe, Craig Alexander, Norman Stadler... see some examples here.
While I wouldn't want to think what would happen to me if I tried to race some of those positions for 100+ miles at a time, that isn't to say that there aren't athletes who do amazing things on the bike.
However- The thing to keep in mind during a tri... "bike for flash, run for cash"
It always comes down to the run, if you can't run after the bike than you can't win- and that is what drives some bikes to be setup with a little more comfort in mind. Most bikes can be used in a huge range of positions- your hard-points and personal preferences are what make the difference.

And swim not to drown...

Yes. A TT bike is powered by a cyclist. A Tri bike is powered by a... uh, never mind. :innocent:

A lot of folks run the 78-degree STA in UCI events, but force their bike into the rules by chopping the nose off the saddle and/or riding waaaaay forward on the nose.

Here's Zabriskie, with his old P3 set up in the 78-degree configuration, AND riding on the nose:

http://upload.wikimedia.org/wikipedi...Time_Trial.jpg

For all practical purposes there is no difference between TT and Tri bikes. There are some differences in setup depending on the length of the event in Tri, but the bikes are ultimately the same.

And if you're a regular old USAC cat racer, the UCI rules don't apply to you anyway.

Skinsuit

Vs. Panties


http://www.dkimages.com/discover/pre...844/810401.JPG

Any thoughts on sizing, I ride a 60 Trek Madone, that roughly translates to a 58 for many other bikes. I 've read to go small, but bigger (58/60) TT/Tri bikes are a bit rare around here so often difficult to test ride. Especially if I wanted a Cervelo, or something other then a Trek TTX.

IN GENERAL, people usually end up on a smaller frame for TT/Tri than their road frame. Most of it has to do with the shorter top tubes on the TT/Tri bikes-- My road bike has a 58cm top tube, and my P2C is 54cm IIRC. Makes sense if you think about it, since you're basically putting your elbows where your hands go on a regular roadie. I'm a rare case, though, and ride a 58cm CAAD8 and a 58cm Cervelo P2C.

If you use Competitive Cyclist's fit calculator, there's a TT/Tri calculator that you can link to from the main fit calculator page. Remember to be very precise in your measurements. That'll get you into the ballpark.

funny thing- the swim is the part I'm enjoying the most over the last few weeks... :innocent:

I'll step out before this gets bloody (and before I change my mind and feed the fire ;)... but anyway- If you aren't sure, the UCI rules don't apply to you. Ride whatever you want. All the bikes are higher-end than I'll ever be (and this includes my spec' allez)

Definitely go smaller. I ride a 54 road bike and the 51 P2C is perrrrrrfect.

Oh dear God.

That makes me very happy for the invention of the tri suit.