theviens wrote:
Hi Eric,
Thanks for doing this. I enjoy reading your analysis on everyone.
I have been riding the same bike since I got in the sport 6 years ago (QR CD.01). I bought it because it was a good deal and probably not the best fit for me. When I had it fit, the fitter says it was long for me (5'7, 145lbs). I also have a bad lower back. We have it stacked and stemmed up for those issues. Definitely not the most aero. But I feel comfortable on it. I tried the P5D which I loved, except for the base bar. I felt very limited climbing with it that low, it will probably irritate my back, and it does not seem to be able to rise. The P series looks better and more adjustable for me. I tried a 51 and it felt awkward. I may need a 54? Would I be better of just getting the frame and customizing for fit of cockpit and crank lengths for example? I have tried to attach my retul fit and a picture of me riding. What is a remote fit you mention in a few posts? Thanks for the thoughts, time and recommendations. I am ready for a new bike! Todd
When another fitter says says a bike is too long for someone, I usually start salivating at the thought of someone being on a properly sized bike! Let's have a look....
Looking at your bike fit photo, you seem upright and a little slack, IOW you're not taking advantage of the longness and lowness of the QR CD.01. This could be for a number of reasons, not least of which it's an oblique angle photo and not the best perspective, but perhaps it's because you haven't had the postural coaching and saddle choice coaching that would enable you to do what a time trial allows you to do with your body. Even with a bad lower back (which I have as well), you can get into a reasonably orthodox and aero position if you keep your back neutral and roll your pelvis forward instead of bending your lower back to get to where you need to go. This effectively lengthens your upper body, and thus long and low frames come in handy when you have this posture. The key is the saddle, and how the aerobars catch you.
With a Pad Stack of 682mm and a Pad Reach of 411mm, your current Retul fit numbers, you're an odd duck, something is up. Very upright or high Pad Stack for someone of your height. Off the charts high for a 51cm P5d and off the charts high and left (ie. slack) for a 54cm P5d. You're even too high for a 56cm.
I hear you about the lower back issues, and I hear you about the basebar, but I feel like putting a band-aid on those problems is a side issue, and we need to get to the root of the issue, the cause of what's going on. There is no reason why a lower back challenged person (remember, me included) can't have a good TT position with the right saddle choice and sitting and postural coaching. I'm also not buying the theory that the P-Series is more adjustable or more appropriate for you, not for the reasons you're giving. Follow me here...
For example, if you came down 2mm to 680mm and added 22mm (not even an inch) to your current position, you'd hit the very upper very left quadrant of a 56cm P5d. This is very easy to do, just with posture, and if you slid your saddle forward to help out it's even easier.
To hit a 54cm P5d, the very upper left quadrant, you'd need to lower your Pad Stack to 662mm (18mm, again less than an inch), and add 7mm of reach to 418mm, which is barely even noticeable. Between the two options, ie. adding an inch of reach to hit the 56cm P5d or subtracting an inch of stack to hit the 54cm P5d, the reach is an easier as, unless you went with shorter cranks in which case it would be a wash.
At any rate, after my hypothetical adjustments to you here, you're *still* at the very upper very left edge of the fit charts, for either a 54cm or 56cm P5d, and that's not something I would call orthodox. You'll be the same on a P-Series. Let's address your fit first and your orthodoxy and see if we can't crack the code on the saddle in order to get your back in a neutral posture effectively lengthening you and lowering you. The more I think and write about it the more I think short cranks and a saddle intervention and postural coaching are what you need.
(I should add here that a EX10 mono-riser from the P3x is something you certainly should do, it adds some reach flexibility fore and aft as well as a native tilt function, which will help you)
Finally, stay away from a 51cm bike at all costs.
Make sense? Shoot me a PM and we can talk more or I can find you a fitter. If I had to go with my gut I'd say get the 54cm P5d with the EX10 tiltable mono-riser.
Eric
Eric Reid
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