Hi Ian,

Thanks for doing this. My numbers are from a bike fit that is 4 years old. There have been very little changes since then and has been very comfortable up to ironman distances. Will this still work? I will give you all the numbers I have and hope that is what you are looking for. I am considering the X PR or the V PR.

Saddle Height: 780 mm
Saddle Setback: 11 mm
Arm Pad Stack BB: 678 mm
Grip Width: 117 mm
Frame Stack: 539 mm
Frame Reach: 420 mm
Arm Pad Reach: 397 mm
Arm Pad Drop: -92 mm
Arm Pad Reach BB: 407 mm
Grip Reach: 750 mm
Grip Drop: -84 mm
Arm Pad to Grip Reach: 354 mm
BB to Grip Reach: 761 mm
Arm Pad Width: 230 mm

Thank you. Let me know if you need anything else.

Hi Ian,

Thanks for the reply. I am surprised that I am an outlier. There are definitely days that I feel like #5 applies but in regards to the bike fit I'm not sure this is one of them. I think I am average physique. The fitter did recommend that I go from 175 to 170 crank.....I never did. After looking back at some pictures of my fit it does appear that my hips are behind the BB but TBH I'm not sure what I'm looking at.

I have a 2010 Felt B16 size 56. I am 5-11 with an inseam of 31 and my saddle height is 780 mm. If you think it will help I am happy to send you the Retul report (with pictures) to your email listed in your slowtwitch account.

I would also like to get a list of fitters around the Sacramento/SF Bay area, in case I go that direction.

I'm willing to be the numbers I need are in here but I need a reference to A-G.

Ian

Lehrn2lose,

I want type out my thinking step by step because my process might reveal more information that will lead us to success. I need Pad Y and Pad X to prescribe a bike. The Slowtwitch icon you included doesn't have Pad X/Y on it which leads me to believe that it's really old - we live by Pad X/Y now and it's included in all our modern measuring and recording.

Eager to help.

Ian

sfdhoseman,
Well, #6 could have been "your cranks are too long" and that is certainly part of the issue here. If you had just come with morphology (height and long legs) I'd have guessed your Pad Y around 658 (only 20mm diff from your 678) and Pad X near to 460 (a hundred miles away from the 407). I hope you have a pre-fit done and come back to this thread with the numbers to compare.

The fitter you need has to have all three of these elements

1. Educated in the tri position
2. Experienced in fitting the tri position
3. A dynamic fit bike

Your options include..
Terry Gerardo, Sportsbasement Presidio
Gino, Sportsbasement Walnut Creek
Ceaser or Kevin at 3D Bike Fit, SF

The fit should be done on maximum 165mm cranks (prolly best at 160). When the fit is done you'll have two sets of numbers: 1) Pad Y and Pad X. Bring 'em back to me here and I'll prescribe with precision. 2) All your fit coordinates: seat height, set back, pad elevation, pad width, aerobar tilt, cockpit distance, etc. etc. Those numbers are what you are paying for and getting them before you order the bike is the smartest thing anyone can do. When the bike arrives go to a mechanic (or do it yourself) have the bike positioned exactly to your coordinates from the fitter's numbers. Ride it a while - progressivley: 60min, 90min, 2 hours then call the fitter and say either a) it's perfect, thank you or b) I've got a couple of minor issues can I drop in for a quick tweak.

I want to toss out a couple of other tid bits can assure a great fit. 1) DO NOT SETTLE for an "okay" saddle. Make the fitter put seveal under you on the dynamic fit bike so you can find one that feels great when you're sort of perched on the nose of it (see pics HERE and HERE) adn 2) go ready and willing to ride hard for ~7 minutes towards the end of the fit. When you and the fitter think you're close to the perfect spot have them up the resistance (to your 40k race pace effort) and ride there for 7-10min while you feel for changes you might need, they tweak while you're pedaling, and you just say "better" or "worse" til the fine tuning is finished.

Eager to hear back,

Ian

Lehrn2lose,

I want type out my thinking step by step because my process might reveal more information that will lead us to success. I need Pad Y and Pad X to prescribe a bike. The Slowtwitch icon you included doesn't have Pad X/Y on it which leads me to belive that it's really old - we live by Pad X/Y now and it's included in all our modern measuring and recording.

Mathematically.... I can get Pad X by subtracting B and D from C. Let's see what happens...
B is set back and it's 75mm - that's a big number for setback, I find it slightly dubious - but there could be a good explanation: you're on a crazy short saddle (like a BiSaddle) or you're incredibly tall, even taller than an 808 seat height would suggest. There could be a bad exlanation: this is a road bike with a proper road bike/shallow seat tube angle or the fit is created around an unusually (read: out of date) 73ish seat angle or the cranks are very long 175+ and the seat position reflects that or some such thing.
D is the extension length - back of pad to tip of aerobar, it's 405mm

So 75 + 405 = 480. If I subtrack 480 from C (the full cockpit: nose of saddle to tip of aero extension) 851 - I get 371. A Pad X of 371 to the back of pad is too short to be logical. It is a number that is an outlier on THIS GRAPH and no QR bikes (no bikes at all?) go down to 371.

I'm alwasy worried that I've made an error in a process like this so there's a way to double check it. F on the chart is another cockpit measurement (nose of saddle to back of pad) and it's 540mm. If I subtrack the setback of 75mm from 540 I should get Pad X and the same number calculated above: 540-75= 466. Now that's a Pad X nubmer that I can believe in! But I still can't pull a Pad Y off of this that I'd be confident about...I mean I could take seat height of 808 and subtrack pad elevation (E) 120mm and get 688 but there's some noise in that.

I'd like to compare 688/466 to a formula that I use. Please give me some basics: how tall are you, what is your inseam, and do you have any drastic abnormalities? And what bike are these nubmers from, have there been any changes since the fitting that yeilded these numbers, how long are the cranks, and are you happy with the position? Any info in our around that would help guide me.

Eager to help.

Ian

Ian, first thank you for taking the time to respond to my post and please accept my apologies for providing the wrong information but it is still the diagram listed under the “bike fit manager” when I view my profile. I don’t have access to the bike at the moment and the dimensions were provided to me from my fitter 🧐.

I don’t think I have any drastic abnormalities but it really depends on who you ask 🤔. I’m a little bit over 6’1”. I did have a BiSaddle on the previous bike and I think I was happy with the fit until the day of the accident. I had one 70.3 and 140.6 on it. It was a Medium Speedmax with 170mm cranks and I included a photo from Arizona below.

Lehrn2Lose,
The position in your pic looks really good to me. I'd like to presume your Pad Y at ~655 and your Pad X ~500. You could fit on either the 54 or 56 V-PR. I like the 56 better here's the prescription..

Ian

i am not the guy who'll run this process for you in this thread. but....

1. go back to your retul fitter and:
a. have him move you successively forward in the saddle, pushing your aerobars forward the same amount, and lowering your aerobars gradually.
b. if you like each successively forward and lower position better than the last, keep going until you find yourself too forward and too low.
c. the last place you chose, before you went too far forward, take the pad x and y of that position.

2. you'll then find that your proper QR size is a 54cm or at most a 56cm.

3. i take back point #1 above if you already did this process with your retul fitter. and, i assume you did this process on a fit bike, such as a retul or a purely custom or a guru.

4. just going by the numbers, i really question the fit, and a really question the advice on size you were given by QR. the folks at QR should've reacted with the same sort of response i'm giving you here. it's malpractice to sell a 6'1" fellow a 58.5cm PR series frame. i'm 6'1" and i ride a 54cm, though i'm on the border between that and a 56cm. the reason they recommended 58.5cm is because your pads are so high. but a 58.5cm size will be way too long for you.

my instinct is to tell you to go back and get your money's worth from the retul fitter, unless he or she executed the fit properly and there are facts about you of which i'm unaware.

and finally...

you should not have to ask for a photo. you should've been given a video. go back and get one and post it here.