determinator wrote:
ericMPro wrote:
determinator wrote:
Hi Eric,
I’ve attached my last Tri bike fit. Apologies as the measurements are different to the ones you specify.
Sadly don’t have this anymore so can’t input the x and y coordinates you refer to. Had a look at my road bike but not all that helpful.
It was a 54 P2, I’m 176.5cm and longer torso and shorter legs. Bars were 3T aura pro. I have long arms. Saddle height is 77cm from BB. Looking at pics of me on this I do wonder if it was a bit small as knees and elbows were a bit close.
Interested in a new p series, p3x or p5d, whichever fits best. Mainly olympic distance and 70.3s and potentially IM eventually. Can DM you other fit images with me on it if helpful?
Many thanks.
OK, let me work on this... do you have a picture of you on the bike?
Hi Eric,
Thanks for getting back to me, much appreciated. Please see attached fit photos.
Thanks. I think I get it now...
OK, so before we begin you need to know what my fit philosophy and what my priors and tendencies are, as that knowledge will help you understand what I'm going to tell you and also how I might be different or the same as other fitters.
Generally, I feel like you should always use the right tool for the job, that your bike should work for you and not you for your bike, that you should always get the fastest bike for the purpose (or future purpose!) all things being equal, and finally and most importantly as it relates to fit and orthodoxy I feel that you should always get the longest bike possible that is still able to get low enough for your position (or future position!).
This last part is pertinent because I tend to trend longer than my peers with bike fits, which then leads to clients being on a bike one size bigger than they thought, than their peers thought, or their LBS thought they should be on. IMO, there's no point in a bike that's too small/short! Spacers under stems are not a good idea, unless you are a UCI Pro Tour cyclist doing an ITT in which case I could make the point that smaller is better, for a number of reasons that don't really apply to us and merit passing over here. Too long OTOH, as long as it's low enough, is like having money in the bank for a rainy day in the future. If your position change (and it almost always changes in my direction), your bike will work for your new position. If you get a too small bike, it won't. This reasoning also informs which bike you choose. Your focus is short/medium *now*, but an IM is in your eventual future. Pick the bike that can do all three as functionally and as aerodynamically as possible.
Now, you're admittedly a long torso guy, you thought your bike was a little too small from your perspective, and then finally me looking at your pics I felt the same way. I'd call that good supporting evidence for a decision. You could do with a longer bike. "But you're only 5'9"!" Don't listen to them. The bike works for you, not the other way around. We'll put your contact points in space and bring the bike up to meet them as functionally and as aerodynamically as possible. The size of the bike compared to your height is irrelevant when you're on a well designed well built bike doing triathlon. If it fits it fits.
I'm estimating your current pad stack and reach is 630mm pad stack, 435mm pad reach. I feel like you could be about 50mm longer once you figure your fit out. You need a bike that is able to hit 485mm to back of pad eventually. Your current fit would be a 54cm P5d, but as you add reach you move into the 56cm P5d realm. The minimum reach for a 56cm P5d at your pad stack height is 448mm. I feel very confident that you could handle a sudden 15mm increase in reach if purchasing the P5d as a new bike. I don't feel confident that a 54cm would serve your needs in the future as your fit evolves.
By that rationale, and with those coordinates, you'd fit a size M or size L P3x, and you'd lean toward the size L. Minimum pad reach for the size L P3x is 430mm for you, so already within range, and goes out to a whopping 510mm at your stack height. This is your bike... size L. The P3x would carry and store all your nutrition, hydration, and flat kit stuff for an IM but would be plenty fast and functional for OD or 70.3. Actually, in the times of COVID and what I think racing will look like going forward, the ability to do a half IM self-supported will be useful as well. Self-supported but totally aero storage for the various bottles you'd need to port for a self-supported HIM.
Does all of this make sense? I'm not saying a P5d can't be kitted out to do an IM, just that the P3x would do it as well as the short course stuff just as easy. Same with the sizing recommendations... do those make sense as well? Let me know.
thanks,
Eric
Eric Reid
AeroFit |
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