I recently was fitted for a tri bike (using something called a guru dynamic fitting unit if that matters). I’ve ridden on road bike + aero bars for years but want a TT bike now. The fitter told me ideal stack 495-525mm and ideal reach 377-392mm. He translated this to 2 bikes (of course the brands they sell in shop): Felt IA disc 51 cm and BMC Timemachine 01 disc Med-short. Leaning toward felt for aesthetic reasons.
However I wanted to compare to cervelo. I took those numbers to a cervelo retailer (and checked their fit measurements online). The cervelo guy eyeballed me and said “51 cm†for P5 or P-series…. But looking online the P5 reach is way too big and P-series a tad too big… according to numbers none of the cervelo bikes would fit me at all.
I’m not strangely shaped: I’m 5’6†female, 135lb, slightly short torso with 32†floor to crotch height. Is it possible that the cervelo bikes really won’t fit me as well? Or are cervelo bikes measured differently? The cervelo guy said the p-series is really forgiving and can be tailored to any body but I’m wondering if I should still just go with felt since the numbers match better?
I recently was fitted for a tri bike (using something called a guru dynamic fitting unit if that matters). I’ve ridden on road bike + aero bars for years but want a TT bike now. The fitter told me ideal stack 495-525mm and ideal reach 377-392mm. He translated this to 2 bikes (of course the brands they sell in shop): Felt IA disc 51 cm and BMC Timemachine 01 disc Med-short. Leaning toward felt for aesthetic reasons.
However I wanted to compare to cervelo. I took those numbers to a cervelo retailer (and checked their fit measurements online). The cervelo guy eyeballed me and said “51 cm†for P5 or P-series…. But looking online the P5 reach is way too big and P-series a tad too big… according to numbers none of the cervelo bikes would fit me at all.
I’m not strangely shaped: I’m 5’6†female, 135lb, slightly short torso with 32†floor to crotch height. Is it possible that the cervelo bikes really won’t fit me as well? Or are cervelo bikes measured differently? The cervelo guy said the p-series is really forgiving and can be tailored to any body but I’m wondering if I should still just go with felt since the numbers match better?
2 questions:
have you been fitted for a tri bike? or is your fitter using your road fit numbers to make a guess at your likely tri fit coordinates?
do you have a pic, or a video, of your fit session?
beyond that, you can almost certainly fit just fine on a cervelo and, in any case, cervelo’s frames and felt’s tri frames share very similar geometries, so it’s unlikely that you can fit one but not the other.
I wish I had photo/video… hadn’t researched the process before I did it!
That was my gut about cervelo… why do people do a complicated fit before picking a bike if most frames will fit well? The cervelo dealer said that doing a detailed fit before picking a bike is almost like “putting the cart before the horse†but I’ve read conflicting suggestions on approaching new bike purchases…
I wish I had photo/video… hadn’t researched the process before I did it!
That was my gut about cervelo… why do people do a complicated fit before picking a bike if most frames will fit well? The cervelo dealer said that doing a detailed fit before picking a bike is almost like “putting the cart before the horse†but I’ve read conflicting suggestions on approaching new bike purchases…
your fitter was right. in theory. and would be even more right if this was a road fit, because over the past 5 to 10 years tri bikes have become more adjustable and more easy to accommodate all riders, while road bikes have diverged in their geometries and have become less adjustable. in any case, the value of doing the fit on the fit bike - and the guru is the best - is that you can dial in your exact fit coordinates and then transfer them onto the new bike.
now, to get to specifics, here is what your fitter told you: “495-525mm and ideal reach 377-392mm”. great. but those are frame stack/reach numbers and this really won’t help you. what you need are pad x and pad y, aka pad stack and reach. where your pads sit above and in front of the BB. give us these numbers. if you weren’t given these numbers, go back to your fitter and ask for them and report back here.
FWIW, those are very close to my fit coordinates. Stack was 535, reach was 422 to back of pads, so make that 465 to pad center. I had a Felt IA16, 51cm, but swapped the stock stem for the 110mm Dagger stem. The bike shop where I had it put together accidentally add 10mm stack to my bars and it was just fine, so more like 545 and 485 when all was said and done.
I’m also 5’6" and IMO not oddly shaped.
I loved the bike, I recently sold it because of time constraints, and I’d recommend it except for maybe the parts availability and potential for problems with customer service. I don’t think you’ll have those problems with Cervelo, so if Dan etc say you’ll fit on it, I’d consider the option.
Also FWIW, I might shop elsewhere considering that comment about not getting fit before the purchase…seems sketchy.
(EDIT: I reread your post and thought you were referring to pad x/y as Dan asked. My fit numbers above are pad x/y, not frame numbers)
It’s good to hear about your parts/customer service experience with felt. Is your thought about cervelo in regards to cervelo being more compatible with off-the-shelf type products? Or that cervelo is just a bigger company? I recall maybe reading a review somewhere about felt — they were complaining that something on it couldn’t easily be replaced with non-super-pricy felt component but I can’t remember…
Lol I understand about the sketchiness of the fit-after-you-buy comment… BUT!!! the SAME guy put his money where his mouth is and let me ride a new p series 51 cm yesterday on the roads and it fit great!!
Im now thinking with some of these tri bikes that their cockpits are just so darn adjustable that (as long you get the right frame size) it can be fit to any body/aero position.
Im still waiting for my “pad x/y†numbers…
The felt is gonna be about $8500.
The cervelo is gonna be $6800.
The felt guy is the one I’m waiting on for pad coordinates (I’m sensing that if the fitter is potentially fitting you for a brand they don’t sell… well, they may not wanna help…)
I’m now leaning more heavily toward cervelo, but still open to suggestions!
I’m no expert, I just see a lot of people having trouble getting parts from Felt right now. That could change but who knows…plus it depends on the parts. When I bought mine I only bought the frameset so I wasn’t too worried.
You gotta go with the bike that fits you, but you also have to like that bike! Also if the Cervelo is cheaper that’s a big consideration.
“Lol I understand about the sketchiness of the fit-after-you-buy comment… BUT!!! the SAME guy put his money where his mouth is and let me ride a new p series 51 cm yesterday on the roads and it fit great!!”
Good question. I guess it felt comfortable and bike felt responsive and handled nice, but that may be a novice answer! I’ve ridden aero bars but on a road bike for years. Is tthere a way to assess a fit more precisely? (Edited: I mean a formal fit session will do this, but I’m wondering more subjectively as the rider… if I bought the cervelo, I’d get a very formal detailed fit on that bike. But from a rough eyeball fit and test ride it felt like the frame/fit was good)
The formal, detailed fit should be done before buying a bike.
You should at least get the pad x and y from your fitter and see what Dan says about it.
Your fitter should also provide some pictures and video of the fit. It would be a good idea to post them here to see what the real pro fitters have to say.
I really appreciate all your help and comments on this.
Fitter gave me: X/Reach is 440mm, Y/Stack is 710mm, measured to pad center
He feels BMC TM med short is best fit with felt ia 51 another option, but I’m looking into cervelo p series. These number (even with 1-2 cm less for back of pad correction) make it look like the bike won’t fit at all…?
Still no photo/video… I’ve learned my lesson here!
I really appreciate all your help and comments on this.
Fitter gave me: X/Reach is 440mm, Y/Stack is 710mm, measured to pad center
He feels BMC TM med short is best fit with felt ia 51 another option, but I’m looking into cervelo p series. These number (even with 1-2 cm less for back of pad correction) make it look like the bike won’t fit at all…?
Still no photo/video… I’ve learned my lesson here!
there are 2 parts to a fit session:
part 1: establish ideal fit coordinates (saddle height, cockpit length, armrest elevation relative to the saddle, stuff like that);
part 2: find the bike(s) that best match your fit coordinates.
your fitter has done a good job at part 2. the problem is, if you don’t do a good job at part 1, then you precisely match the perfect bike that mates to your shitty bike position. this is what i fear in your case.
this is why we really like to see a pic of you aboard the bike. a pic in profile. aboard the fit bike. better yet 10sec of video. because, in your case, here’s what the video is going to show: you’re pedaling along at 50rpm with almost no pressure on the pedals. that’s not how to fit. that’s like you testing your nutrition plan for an ironman while in your easy chair watching a turner classic movies marathon.
the reason i surmise that this is how your fit was done is because your pads are so high. you have adopted the best position for warching turner classic movies while riding a bike. so…
that 440 is really a 400mm to pad rear, and i don’t have a big problem with that. but how did you end up so high up in the air? why did you not choose a lower position? because you were offered a lower position, is that right? or were you not offered that?
Dan is the man, obviously, and so great you are posting on here before making a potentially incorrect purchase.
Just to add my two cents….Cervelo all the way….(if it fits).
I could make a long list of the reasons why, but in essence there is a reason why they are where they are at in terms of sales volumes etc. No disrespect to Felt (owned one) and BMC (never owned), just think you would be better off long term with a Cervelo versus those two brands.
Still no photo/video… I’ve learned my lesson here!
just, fyi, if you went back to your fitter, it would take no more than 5 minutes to set up the fit bike in your final position. and because it’s a guru make that 1 minute. you hope aboard, the fitter takes your cell phone and captures a 10sec video. you post it here. the only time it takes is to go to the fitter and come back. you might want to consider that exercise bearing in mind everything at stake.
i also think, however, that this revisit to your fitter could be more productive if you kind of went over the fit again. with more resistance. pedaling harder. like, as in race pace. if your saddle height is, say, 70cm, or 71cm, then your bars are higher than your saddle. is that the position you want?
I really appreciate all your help and comments on this.
Fitter gave me: X/Reach is 440mm, Y/Stack is 710mm, measured to pad center
He feels BMC TM med short is best fit with felt ia 51 another option, but I’m looking into cervelo p series. These number (even with 1-2 cm less for back of pad correction) make it look like the bike won’t fit at all…?
Still no photo/video… I’ve learned my lesson here!
Wondering if that stack measurement is a typo from your fitter.
I ride a ‘54’ felt, and have a stack of 64cm, and I think I could only go a max of 1cm higher on this frame. Not sure how a 51 can achieve a pad stack of 71cm!!!
Here is a pic of my 54 felt with the 64cm stack for reference.
At first, I thought surely the 710mm Pad-Y was a typo… but it was not. I called fitter to figure this out, and he said a lot of words including “amateurs” like the “comfort” of the more “upright position” yada… My intent was to be fitted to a more aero bike, not to replicate my road bike +aerobar fit I already have. His plan was to set me up with the BMC or Felt with enormous risers to raise my bars up…
So, Dan/ST community, thank you for saving me from looking pretty darn dumb on a super aero bike in the LEAST aero position possible!!! I mean can you imagine…?!
I’m annoyed with this fitter. I don’t really want to spend the hours driving back to him; I certainly don’t want to give him any more of my money.
Given other ST member’s tips supporting cervelo over felt/BMC, I’m WAY more interested in a cervelo now. Ideally P-series.
Any chance you all could comment on the general frame fit of this P series size 51 my local bike shop let me try? Of course it’s not fitted specifically to me. My plan would be to buy this one (if it generally fits) then take it to a different (Dan-approved) tri bike fitter to set it up more precisely. (And for reference I’m 5’6, saddle height 725 - one measurement from the ‘shitty fit’ that might be correct.) I’m very interested in buying sooner rather than later because ordering new P-series at this point is likely a several (potentially 6+) month wait… hence why I don’t love idea of redoing the fit THEN buying after.
I have a video but not sure how to attach, let me know if that’s needed
