Depending on how current you are, you either ascribe to the theory that seat angles are trending forward or backward. From where we sit, the history goes something like this:
Seat angles were, of course, shallow (73 or 74 degrees) prior to the introduction of triathlon-style handlebars in 1987. By 1990 or so, quite a few people were riding forward with seat angles up to and exceeding 80 degrees. In the late '90s many riders started to move their saddles back, or if they were new triathletes they never did move their saddles forward.
Further entrenching that view, at the pro level, was the fact that athletes felt better—felt more powerful—when racing ITU-style races on their shallower road race bikes. They made the assumption that this would translate over to no-draft racing. But the Ironman specialists found out that wasn't the case, and while certain short-coursers showed up at Ironman races with their laid-back bikes, the long-coursers generally outrode them on their steep bikes and then outran them with fresher legs.
On our introductory Kona Survey page we go over the seat angles used by the pros, and this should demonstrate that the best athletes and fastest riders tend toward seat angles at 76 to 79 degrees. Many of these riders rode with a slacker angle back in '99 thru '00 and have gradually steepened their positions. Most of the top finishers—Tim DeBoom, Cam Brown, Peter Reid—have steepened their positions over time. Others, primarily most of the Germans, have always ridden steep.
The trend back toward steep angles has yet to trickle down to the age-group level. In fact, it's gone counter to the trend among the pros, as can be seen in the two graphs above.
It appeared perhaps a good idea for us to demonstrate graphically the difference between the two set-ups. The photo at left is of Spencer Smith at Kona. His position was quite rearward, and there are several notable aspects to this. The angle between his torso and his upper arm is greater than 90-degrees, as is the angle between his upper and lower arms. This is in contrast to what the Slowtwitch site recommends on its tri bike fit page, where right angles are recommended.
Smith rode well enough in Kona—though not overpowering—but immediately struggled on the run and dropped out with leg cramps after several miles. He opted to change his position quite radically for Ironman Florida, the story of which is chronicled elsewhere on Slowtwitch.
The results of his repositioning are shown in the photo at right. The differences are strident. His saddle nose was moved from about 6 cms behind the bottom bracket to even with it, or perhaps 1cm behind it. Moving the saddle forward allowed Smith to move the bars lower in front, although not that much. As can be seen, Smith's new position is not overly aero but is very powerful while being no less aero than he was before. It is easy to see that Smith's hip angle is much more open now than was the case in Kona.
He is much more compact in the "cockpit," and his upper arms now form a right angle with his torso. Smith's forearms point downward, a phenomenon we discuss in our bike fit section. Smith has always ridden that way.
Spencer Smith made the initial decision to ride in a more relaxed set-up because he did not think it would be possible to ride 112 miles with a steeper bike configuration, but he appears to have proven to himself that that is not the case.
It is striking to consider that while Kona's pro field went from two-thirds steep to better than three-fourths steep from last year to this, Kona's age-groupers went from 60 percent steep last year to almost half riding shallow in 2002. There's obviously a significant disconnect between the two groups. Also interesting to note is the trend line among pros over the past few years. In 1998 pros were positioned steep at a rate of 73 percent. That necessarily means that a certain number of them made a decision to ride shallower between '98 and 2000, only to revert to a steeper angle this year.
We suspect the disconnect between the pros and age-groupers is based on the lag time between a tactical reality at the pro level and its incorporation by age-groupers. Perhaps local bike shop experts are a couple of years in arrears in their understanding of the trends, and are communicating their (outdated) understanding to their customers. Maybe it's a function of the mix of bikes, road versus tri, that are getting sold to triathletes. Certainly it is the confusing signals being sent out by triathlon's media.
There is a wide range of accepted bike positions, and Kenny Glah, for example, is one of those 23 percent of pros who rode Kona in a slack angle, and rightly so, for him. Our interest here is not to suggest an angle everybody ought to ride in. There is no "best angle." Rather, we're just reporting in our Kona Survey what we saw, and speculating why it is we saw it.
