That seems oversimplified for the ht, what is the difference in SURFACE AREA, not the narrowest point?
It is oversimplified and I’ve tried to think of a simple way to get a better measurement. Unfortunately when I first started measuring frames I didn’t think to get the width at the bearing on all of them (I did for noticeably waisted ones like trek). Also when you’re in specializeds booth at eurobike it is hard to take exhaustive measurements. Besides which, is surface area direct frontal area or taking curves/nosecones into account).
I don’t think “fits” have been done using standover height as a guide in a couple decades. Since when is standover an issue on a “medium” frame?
That’s exactly my point. The issue is more one of reach but having the sloping top tube gives people a bit more range of possible frame sizes (thus options for reach) especially for people with shorter legs compared to torso or who prefer positions that use up a lot of ‘top tube’ length.
With regards to sloping top tubes, in my experience the only thing it gives you is more frontal area.
That depends on how they are incorporated in the design. Not an issue in this case.
With the variable position posts, that won’t accomadate different sized riders, only a wider range of seat angle preference.
It’s all part of the puzzle. I don’t think you will any experienced fitters who will argue that having more options for position is a detriment to helping a variety of riders achieve a variety of fits and position preferences.
For example, I wouldn’t ride a large size if I rode slack, I’d ride a medium (yes, at 6’2"). The large couldn’t be made to fit just because I could ride it at 73, 76, 79, or 82 degrees.
That’s exactly my point. The issue is more one of reach but having the sloping top tube gives people a bit more range of possible frame sizes (thus options for reach) especially for people with shorter legs compared to >torso or who prefer positions that use up a lot of ‘top tube’ length.
The reason there is no standover issue is the short HTs, the midpoint of the top tube won’t vary in height much thanks to the slope, especially when there is that hump up the front. 4 sizes suggest that they’re not looking at people being able to have multiple options.
It’s all part of the puzzle. I don’t think you will any experienced fitters who will argue that having more options for position is a detriment to helping a variety of riders achieve a variety of fits and position preferences.
Actually I often argue that giving people too many options is bad. While it is good to have the facility for a wide range of setback it will allow poor fitters (they far outnumber the good ones) to “make it fit”
For example, I wouldn’t ride a large size if I rode slack, I’d ride a medium (yes, at 6’2"). The large couldn’t be made to fit just because I could ride it at 73, 76, 79, or 82 degrees.
Well, good thing you work for Felt then!
My issue with the large would be the cross headset meaning I couldn’t get the bars low enough. To me that is a part of the puzzle they overlooked when coming up with those nifty brakes.
A good unbiased opinion from a Specialized sponsored athlete.
Yes, actually you’re right. I gave a bunch of basic unbiased facts that apply to all bikes, not just Specialized. I hope they help.
the P3 is likely to be somewhat soon replaced by the P4
Have any hard evidence of a P4 any time soon? Waiting for a bike that may be up to 11 months away (assuming it is even that close) seems foolish if you want a bike THIS SEASON.
A sloping top tube, gives a front surface to a tube that doesn’t need to have one. When it is horizontal, looking at the bike from the front, the front end of the top tube is behind the head tube. When it is sloping, the bottom side of the top tube now has a frontal area for wind to hit that it need not have.
I know a sloped tube is going to present more frontal area on its own, but if the toptube is sloping it is behind the headtube, and if it slopes enough, the downtube. Beyond that, it is still going to be in dirty air from the front of the bike and the rider’s legs. I’m sure its been studied ad nauseum, but it is interesting that one company is featuring it, while the majority are not. What did they see different in development? (or is that assuming too much?)
Honestly, I like Specialized bikes a lot. Does the frontal area of the top tube make a big difference? Certainly not. Does it make some difference? I would guess yes.
Why did Specialized do it? Probably so the looks of the Transition are similar to the looks of the road bikes, the Tarmac, Roubaix, etc.
A sloping top tube, gives a front surface to a tube that doesn’t need to have one. When it is horizontal, looking at the bike from the front, the front end of the top tube is behind the head tube. When it is sloping, the bottom side of the top tube now has a frontal area for wind to hit that it need not have.
That frontal area is otherwise taken up by the seat tube. It’s essentially a wash. Especially they way Specialized designed it. Don’t forget, to a large degree this bike was designed ‘in the tunnel’ with help from aero experts like Cote et al.
No, it’s not really a wash because while you have less seattube due to the sloping top tube, you end up with more seat post.
So the amount of frontal area on the seattube + seatpost area will always be the same. All they did was give a frontal surface to a tube that doesn’t need one.
Like I said, I like the bike and it’s certainly not a huge difference, but it is a difference.
In fact, funnily enough, it was superdave who said it himself. Since the seatpost does not have to conform to the UCI 3:1 rule, the seatpost can be designed to a >3:1 chord ratio to be even more aero.
No, it’s not really a wash because while you have less seattube due to the sloping top tube, you end up with more seat post.
So the amount of frontal area on the seattube + seatpost area will always be the same. All they did was give a frontal surface to a tube that doesn’t need one.
Like I said, I like the bike and it’s certainly not a huge difference, but it is a difference.
I hear what you’re saying but I don’t think you’ve really thought this one through…
I guess I can say the same to you and we can agree to disagree
I’ll stand by the simple argument that it’s a nice bike, but they gave a frontal surface to a tube that doesn’t need one. And if you ask me why they did it, I would tell you because they wanted the lines of the bike to look like the Tarmacs and other bikes.
The problem is most of the top bikes were designed “in the tunnel”. They are all pretty damn good, but the tunnel is only a tool and if the designers used that tool perfectly all of the top bikes would be shaped exactly the same.
Hey 44
I was thing on this as I have one of the older Aluminum transitions
What I think we have is like an aircraft wing, if you have two wings of the same length and one is slopped back, you have less frontal area for the same length wing by slopping it back, and it is also a faster wing then a straight wing
So you would think that the same is true for the sloping top tube of the transitions, you’re exchanging seat tube/seat post area for top tube area but by sloping the top tube and you have less over all frontal area.
Dan…
