Finding the right bike from the bars back
Written by: Dan Empfield
Date: Wed Mar 26 2008
Of course, I could've just slapped the thing on any bike, ridden it, and wrote about it. The problem is, I believe in the ultimate utility of a proper bike fit. The top of my saddle is 79cm from, and its nose even with, the bottom bracket. I hold the ends of the aero bars 80cm from the saddle's nose, and my armrests sit 15cm below the top of my saddle. How can I really determine whether I like this Ventus if it's not on a bike providing me my proper position?
All well and good in theory, but since the stem length and pitch are non-negotiable on the Ventus, and since the elevation between the armrest and the handlebar clamp is fixed (well, the elevation that would be there if there was a handlebar clamp), I have to find the perfectly sized frame for this aero bar.
I have to find a frame such that, when I clamp on this bar, it matches exactly my fit parameters. If I can't find that frame then, yes, I can write about the Ventus, and about how it's got its tannins in check and about its nose of berries and a hint of marzipan, but I'll be blowing smoke up skirts and I'll know it and the most discriminating among you will know it.
So, no, I can't do that. I must find the right frame and obtain it. Then I can road test this bar, and then the test will be valid. But how do I find this frame? I asked myself this very question, scratched my head, and then remembered I had a fit system.
My first task was to determine precisely the parameters of this Ventus bar. What was the stem length? The pitch? Where were the aero bar pads oriented, in both the X and Y axis, relative to where the handlebar clamp would be, if there was one?
I put the handlebar config most closely resembling the Ventus on my fit bike, complete with the same extensions in the same length. Yes, the extensions in this Ventus are not those that come with it. The Ventus I was sent had straight bars, and I don't like straight bars. Fortunately, the one modular aspect of the Ventus is its ability to accept any extension as long as the O.D. is 22.2mm, which seems to be the industry standard by consensus. I slapped some Blackwell Wrist Reliefs in the Ventus, and I can already tell I'm going to like that set up, assuming there's a bike under that bar I can ride that puts me in *my* position.
The Ventus' "stem" is pitched parallel to the horizon, so I put a 100mm minus -17 degree stem on my position simulator, aka my "fit bike." I set up the saddle height, seat angle, cockpit distance, armrest drop, and so forth, to match my fit coordinates. Thusly set up, the "bike" under that simulator is the bike I'm looking for.
Well, sort of. There was one fudge. The Ventus has 5cm of elevation difference between the armrests and the virtual handlebar clamp. My fit bike's Visiontech armrest and clamp system has 3cm of vertical displacement between these points. So, when I divined the mystery bike's stack and reach, I simply subtracted 2cm from the stack of the bike I was searching for, to make up for the 2cm difference in armrest elevation.
It's handy that it came out this way, since the CSC team rides both Cervelo and 3T. But this is not the only bike that works. Actually, a case could be made that the 58cm P3C is the better bike for me, at 53.5cm and 44.5cm. Why? Because this bike will fit assuming I place 15mm of spacers under the Ventus bar, to make up for the 15mm this frame is "too low." Why would I want that? Because our stack and reach tables are quite close, but they may be off by 5mm or 10mm here and there due to user error, and I'd like a little wiggle room. So, that 15mm of spacers is unnecessary if the stack and reach I've calculated is spot on, but if it's not, then the P3C grants me some insurance.
But isn't the P3C 5mm too long, you might ask? No, because the P3C's extra 5mm of reach disappears once you stack the bar up with 15mm of spacers (remember, you don't stack straight up when you put spacers under a stem, you stack up and back at 72 degrees or so of seat angle; you lose reach at a rate 30 percent of the height you stack).
Felt's 58cm bikes have a stack and reach of 54.5cm and 45cm. So, they're a very close fit, just 1cm too long, and if I slide those Wrist Relieve extensions 1cm back the bikes will fit me perfectly, except the armrests will ride 1cm further up my forearm. Of course, I would not be able to ride the Felts with the Bayonet fork, since those have stems integrated into the fork, so we end up with dueling integrated stems trying to put a Ventus on a Bayonet.
Giant's Trinity Alliance in size L has a stack and reach of 54.8cm, and 45cm, that is, this bike in L is almost identical to the Felts in 58cm. So, it would work. A Kestrel Airfoil Pro is, in 59cm, identical to the P2C in 58cm, at 55cm and 44cm of stack and reach. The Kuota Kueen K in size 58cm has the P3C's stack in 58cm, so that would work, but like the Felt and the Giant is about 1cm too long in the reach.
Leader's LD735TT in size 60cm has a stack and reach of 55cm and 44.5cm. QR's Kilo and Tequilo in 58cm is close at 54.5cm and 45.5cm, but those QRs are 15mm too long, for me, with this bar, and that makes these bikes just a little too long for this particular experiment.
This doesn't mean I can't successfully ride the S Works or the Slice. I just couldn't ride them with this bar. I'd probably ride the Slice in its 60cm size because I need that bike's longer reach, but it's also got a taller stack. I'd ride it with a bar that had lower elevation armrests, like the Profile Design Sonic Stryke or the Hed one-piece.
All this is to say that integrated bars like the Ventus take some planning. If you think you'll just buy this sexy bar and ride off into the sunset, well, you can, but then you'll be extolling its virtues to your friends, going on about the smoke and vanilla with overtones of licorice and cassis but in fact you've simply purchased poorly. As good carpenters say, measure twice, cut once. My advice: measure twice, buy once, especially with $1200 bars like the Ventus.
I'm very much looking forward to riding this aero bar, because I love its plush armrests and it seems quite ergonomic. But you won't be reading the road test until I get a bike underneath this bar that'll work for me. I'm further down the road of writing that review, since I now have the list of the bikes in the sizes that will work.
Road testing the 3T Ventus aero bar properly required a bit of trigonometry, a dash of ingenuity, and smidge of creativity, some nerve, and a credit card with room on it. 5.05.08
The Dutch Masters (the bike makers, not the cigar makers) have struck again. The Ventus is a tri bar to be taken seriously: not just as eye candy atop the P3Cs ridden by Cancellara and the CSC team. 5.13.08
In about a month, I'll have two bikes in my garage: a P3 and a Slice. The P3 was an output, that is, it was the result of a process. The Slice was an input: It commenced a process. Confused? Let me explain. 4.27.10
It's an integrated aerobar system with pursuits 30cm apart on center, rather than the typical 40cm or 42cm. This bar is crazy narrow. The importance of the Brezza Nano is less what it is than the paradigm it represents. 1.09.12
We take a look at the new Zipp Vuka Stealth aerobar and their unique fit tool, called Vuka Fit. If you've ever been intimidated by fitting an integrated bar on your bike, this could change your perspective. 4.12.13
Earlier in the decade I wrote an article on how bikes are sized, and the gist was that we ought to be looking at bikes from the point of view of head tubes and top tubes, and that's it. -- no more seat tube sizing. 2.19.03
Our primer on stack & reach continues with the second chapter in the series. We examine how stack and reach enable you to understand how a given bike will, or will not, fit you. 2.19.03
In the final chapter of our stack and reach primer, we compare stack and reach with other ways of remaking sizing nomenclature. 2.19.03
Got Bar, Need New Bike :-)
Reviewed by: Steve, Apr 1 2008 5:46AM
Aero Bar Selection and bikd choice
Reviewed by: Tri Dork, Mar 27 2008 9:12PM
Dan (finally, to get to the alleged point) to me, you are triathlons Peter Schwirtlich! I'm sure you have forgotten more about triathlon than virtually all of us here at ST will ever know. Thank you for your insight and thorough investigation of triathlon related problems..like getting the right bike for your aero bars. I read the article with keen interest and thoroughly enjoyed it. I particularly like the noting of the point that stem spacers don't just raise the bars vertically. I knew that, but I suspect many trigeeks would miss that trap for young players. Keep up the good work. I look forward to your next in depth review of a tri topic.
Swapping parts prior to review
Reviewed by: slowman, Mar 27 2008 7:14AM
Reviewed by: Mark, Mar 27 2008 4:35AM
Is there something missing in the second paragraph
Reviewed by: Dennis, Mar 26 2008 8:20PM
"The top of my saddle is 79cm from, and its nose even with, the bottom bracket."
I don't understand what he is trying to say there.