OsgoodZ wrote:
Pad Reach X: 472
Pad Stack Y: 680
Handlebar X: 472
Handlebar Y: 625
Stem length: 90
Stem angle: 6
Stem stack: 40
Stem stack: 45
Spacer height: 45
Head angle: 72
Reach: 410
Stack: 537
Saddle X: 130
Saddle Y: 696
Saddle thickness: 56
Seatpost setback: 0
Seat angle: 79.4
Seapost setback: 763
First things first, there is good information here - enough to determine what bikes fit you well. What's not here is any evidence that these measurements were the result of you being in a good position. So let's take this fit at face value and assume your'e in a great position (and judging by your numbers at the contact points - saddle and armpad positions - it's likely your fit isn't bad).
There's one bit of data that makes me skeptical, though:
Spacer height: 45 WHY??????
Doing this means that your frame geometry values are useless, yet that's the data you were planning to use to make a bike purchase.I posted about this phenomenon on the Fit Forum - fitters using spacers on the fit bike when the fit bike exists partially so you don't use spacers!
So again, let's assume that the fit is good but let's get rid of everything under the handlebar x/y. Using your handlebar x/y and running it through our fit database yields lots of great options (albeit on the tall/narrow side of things). Our tool assumes the fit was done with a Profile Design bar with the armpads set in the middle holes (fore-aft), so if the aerobars used during the fit measure reasonably close to profile T4+ extensions mounted as I described, this is what I get:
- Scott Plasma 10 or 20 in a 56 - fits you really great with the stock setup (frame stack 560, frame reach 417 - you'd configure with 15 mm of steerer tube spacers in addition to the stock topcap).
- Felt IA 56 (with 35-40 mm of armpad pedestals)
- Felt B 56 (frame stack 554, frame reach 420 - you'd use 2 cm of steerer tube spacers in addition to the stock topcap)
- Cervelo P2 58 (frame stack 559, frame reach 437 - you'd use 20 mm of steerer tube spacers in addition to the stock topcap and shorten the stem 1 cm from the stock option)
Additionally, all of these options offer easy adjustment if you want to move to a lower cockpit position.
Now in regards to your original post, as there is a lot to unwind there:
Quote:
I'm 48, mostly inflexible, and competed last year, IMMD, on a road bike with aerobars. My stack/reach results in me having about a 22 degree back angle. I was told that idea is somewhere in the 15-17 degrees.
I don't see many athletes at 15-17 degrees, and I'm criticized by my competitors locally for being "too aggressive" with my fits. Most of the elite athletes I fit ride in the 18-22 degree range.
And your flexibility almost certainly has zero impact on your ability to sustain aero. I'm puzzled why that myth hangs on as well as it does.
Quote:
My stack/reach seem to fit a Cervelo P2 (522/411) very closely and the 2018 Blue Elite Triad SP (526/401).
As you can tell from the earlier part of my post, both of these bikes are too small if the position you gave me is a good position.
Quote:
For the Blue Triad, how would one make up the 9mm shortness in reach?
Would this generally be done by moving the pads on the aero bar or would the fitter change the stem to the next longer size?
Would a novice necessarily notice a 9mm/.35 inch difference in reach?
Just for the sake of the exercise (even though I pointed out this option is too small), it's a good question to answer for the exercise.
The fact of the matter is that the frame reach being short doesn't tell you anything about how to bridge the gap, because you don't contact the frame, you contact the armpads. Depending on the aerobars and their ergonomics, there may not be any difference to speak of, or it may be bigger than the 9 mm you outlined.
Assuming that, indeed, the reach to the
armpad is 9 mm short, I'd prefer to bring the saddle forward if possible. If that's not an option, then I'm moving the pads toward the rider. And if that's not an option, then I'd shorten the stem.
Let's say you're completely stuck as you are being fit on your bike and the budget doesn't allow for the purchase of a new bike. And on your bike, you can't move the saddle forward, you can't move the armpads back, and you can't shorten the stem (maybe because there isn't a stem and you're on an integrated setup). If I encounter that scenario as a fitter,then I look for a different saddle that will push the rider more forward than the saddle they're currently on (and it's obviously got to be comfortable and all of that).
To bridge gaps like the one you describe, there are a number of ways a good fitter can make adjustments and still put the rider in an orthodox position.
Trent Nix
Owned and operated Tri Shop
F.I.S.T. Advanced Certified Fitter | Retul Master Certified Fitter (back when those were things)