a buddy of mine just picked up a Giant Propel Advance that is an aero frame. he's gonna set it up for flats with small rollers and use his parlee as a climbing bike.
this got me thinking, why not just get a TT instead of an aero road frame? since using it on the flats.. wouldn't you go faster as compared to the aero road frame?
well, he mentioned that it's hard to maneuver, especially when you tucked in, you hope it's just going straight and no stops.
what's everyone thought on this?
TT or regular aero frame?
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Jmdesignz2
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TT bikes in general have extremely steep geometry and are designed for use with Aero bars. Not really good for all around riding, maneuvers and sprinting in drops. You might be able to make it work but there are too many compromises.
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To add to that, the steering geometry of a tt bike is quite different... Slack head tube angle and lots of trail gives stable straight line performance but terrible in turns compared to a nice road bike. I think the "steep" geometry referred to above is in relation to the seat tube angle which is much steeper than a road bike and puts the rider farther forward to be able to get in that oh so comfortable aero position 
. Don't get a tt bike unless it's dedicated to tt use.
. Don't get a tt bike unless it's dedicated to tt use.Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ
The benefit is that they are aero. There is tons of info on that debate. But the better point made above about the type of riding you do, it matters. You can't do road race or group ride on a tt bike or road bike with aero bars. But if you want to fly solo you can find time trial races to do and some you can even ride on a regular road bike. If you did a legit time trial and had a good fit you should be fastest on the TT bike.
Coming from someone who's spent many a day pouring over geometry charts, especially on TT/Tri bikes, and who has used several TT/Tri bikes for road bikes, I feel like I've got to put in a word about some of the myths here regarding steep angles, unmaneuverable steering characteristics, etc...
First of all, lets assume a size L road bike that is geometry wise very much in the middle of the field. This would be a 73 degree STA, 73 degree HTA, ~380-390mm reach and 43mm fork rake...
Now, just because the Specialized Shiv Tri numbers happens to be handy in my head... A size M with the setback seatpost (that comes with the frame) gets roughly a 74.5 degree STA, has a 72,5 HTA with a 45mm fork rake and a 405mm reach...
This is typical geo of many, many TT/Triathlon-frames and many have the option of more setback seatposts.
So what we are looking at, is half a degree fork angle difference, which is somewhat offset by 2mm more fork rake to give roughly the same trail. And a seat pushed about 15mm further forward, and a very slightly longer reach. And this is compared to a very conservative example standard road bike geometry.
Then again, there is a new crop of TT/Tri bikes out there and many of yesteryear's bikes had terrible handling thru corners. All aero, no stiffness, wet noodle effect.
First of all, lets assume a size L road bike that is geometry wise very much in the middle of the field. This would be a 73 degree STA, 73 degree HTA, ~380-390mm reach and 43mm fork rake...
Now, just because the Specialized Shiv Tri numbers happens to be handy in my head... A size M with the setback seatpost (that comes with the frame) gets roughly a 74.5 degree STA, has a 72,5 HTA with a 45mm fork rake and a 405mm reach...
This is typical geo of many, many TT/Triathlon-frames and many have the option of more setback seatposts.
So what we are looking at, is half a degree fork angle difference, which is somewhat offset by 2mm more fork rake to give roughly the same trail. And a seat pushed about 15mm further forward, and a very slightly longer reach. And this is compared to a very conservative example standard road bike geometry.
Then again, there is a new crop of TT/Tri bikes out there and many of yesteryear's bikes had terrible handling thru corners. All aero, no stiffness, wet noodle effect.
addictR1 wrote:well aero frames are pretty heavy too.. right?
just not sure what's the benefit in getting a aero frame for regular road bike as compared to regular type of road frames.
Errr...no. Lots of aero road frames under 1kg. Very few TT frames under 1.5...
Are the aerodynamics the same too? Apart from the weight difference of an extra half kilo...
Errr... yes. The IA is a tri bike and thus is designed to be faster at higher yaw which the pro peloton just won't see in a sprint. That IA will be a lot slower in a sprint than that (old ass) AR, and it will flex like it just came out of a Jell-O mold.
Ahh... I see... yes, there would definitely be some obvious disadvantages for the everyday-Joe's daily pro peloton rides, no doubt. I was under the misconception that we were talking about casual riders who spend 90% of their saddle time training, either solo or in smaller groups.
And I realize you have spent a great time sprinting out of corners onboard modern TT/Tri-bikes.
Do you actually have experience? Or are you just drawing conclusions upon hearsay?
...TBH, I can admit that pure Tri-frames have one downside, they are built for IM-distances which require a bit of comfort, i.e the old "vertically compliant", which for most of them is in the rear triangle alone. This is not really uncontrolled flex as much as it is a noticeable"softness", think Solace or Roubaix.
It is perfectly detectable in a sprint, but more as the feeling,of an inertia dampener rather than sketchy flexing.
My Shiv has it more than for instance my previous a bit cheaper Planet X Stealth, but on the other hand the Shiv is a way more velvety ride on rougher roads.
But as for cornering confidence and bombing thru hairpins, they're both on rails with very much no influence from flex compromising the handling nor ability for mid-corner line corrections.
So in conclusion, no you won't get Foil or Hi-Mod "snap" or immediate acceleration, but that is about the only downside.
And I realize you have spent a great time sprinting out of corners onboard modern TT/Tri-bikes.
Do you actually have experience? Or are you just drawing conclusions upon hearsay?
...TBH, I can admit that pure Tri-frames have one downside, they are built for IM-distances which require a bit of comfort, i.e the old "vertically compliant", which for most of them is in the rear triangle alone. This is not really uncontrolled flex as much as it is a noticeable"softness", think Solace or Roubaix.
It is perfectly detectable in a sprint, but more as the feeling,of an inertia dampener rather than sketchy flexing.
My Shiv has it more than for instance my previous a bit cheaper Planet X Stealth, but on the other hand the Shiv is a way more velvety ride on rougher roads.
But as for cornering confidence and bombing thru hairpins, they're both on rails with very much no influence from flex compromising the handling nor ability for mid-corner line corrections.
So in conclusion, no you won't get Foil or Hi-Mod "snap" or immediate acceleration, but that is about the only downside.
It's all about geometry and handling. TT frames are just wrong for road racing conditions. It's simple as that.
How do you figure the geometries are all that different, there is usually about 0.5 degree HTA difference which many times a longer rake makes up for, and many times effective STA's can be had within 1-1.5 degrees of what is considered very mainstream road bike geometry. Granted reach will often be just slightly longer. BB drops will generally be about the same.
So please enlighten me, which geometry numbers are you actually talking about?
Sure, there are extremes in both camps, but looking at the current market as a whole, there is a high degree of overlapping. Especially if you look into brands such as Cipollini.
In fact, a Cipollini RB1000 in size small is about 1,5 degrees STA off of a Planet X Stealth TT-Tri frame in size M, the rest of the figures are practically identical. If you move the seat back about 15mm in the rails in the Planet X Stealth, you've got the exact same fit and the same numbers for handling except a few mm change in seat stay length...
So please enlighten me, which geometry numbers are you actually talking about?
Sure, there are extremes in both camps, but looking at the current market as a whole, there is a high degree of overlapping. Especially if you look into brands such as Cipollini.
In fact, a Cipollini RB1000 in size small is about 1,5 degrees STA off of a Planet X Stealth TT-Tri frame in size M, the rest of the figures are practically identical. If you move the seat back about 15mm in the rails in the Planet X Stealth, you've got the exact same fit and the same numbers for handling except a few mm change in seat stay length...
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If you set up your TT rig with a regular road fit and standard road bars than the worst that will happen is your bike will end up in the freaks topic. But if you show up with aero bars and your body perched over the front wheel then don't bother joining my group ride/hammerfest. A total Fred move. Same with aero bars on a road bike. Go train alone like you're supposed to.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.
