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Does this seem right?
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Hi Everybody,

I sized up a brand-new cyclist last night for a new bike purchase. Sizing for a new bike is something I honestly haven't done a lot of yet, as I've only been pro for less than two years. I get as nervous as a whore in church on stuff like this - just want to do it right. I followed Dan's protocol for sizing, as he describes here, and I'm scratching my head at the results.

Some background:
- 54-year-old female
- Looking for a road bike
- Has not ridden a bike since they came with banana seats in the 70s
- 30.5" inseam
- 53.5" to sternal notch
- 23.5" arm length
- 5' 4" overall height
- 35cm wide shoulders
- Has a $1000 budget for the bike, not including pedals, helmet, and saddle
- Will start out with flat pedals because she's mainly worried about learning to shift and brake first, and will get a trainer this winter, which will allow her to get practice clipping in and out before doing it outside. I suggested she go for mountain bike shoes and Shimano SPD for their two-sided entry, generous float, and ease of walking in mountain bike shoes when she gets to that point.

I currently use an old LeMond Revmaster spin bike with a SwitchIt, adjustable cranks from High Sierra Cycling Center, and an adapter that my neighbor buddy machined for me to attach regular road bars to it. Call it a poor man's fit bike. It works pretty well.

After measuring her, I put all her numbers into a spreadsheet I use for predicting coordinates, using 5 different saddle height measurements (Lemond, Cobb, 109%, etc.) to get in the window. Got everything in place and got her on the bike. Saddle was way too high for her, brought it down, and continued to make adjustments to get her comfortable. Swapped saddles a couple of times, but she wasn't too offended by anything. A relatively flat Selle Royal Seta tilted down just a hair seemed good. After all was said and done, here were her measurements:

Saddle
Selle Royal Seta
Saddle Angle (degrees)
-1.10 deg
Saddle Height (mm)
653 mm
Saddle Setback (mm)
15 mm
Saddle Tip to Bar Center (mm)
390 mm
Saddle Center to Bar Center (mm)
530 mm
Handlebar Reach (X) (mm)
375 mm
Handlebar Stack (Y) (mm)
610 mm
Crank Arm Length (mm)
165 mm
Handlebar
EIS S5
Handlebar Width (cm)
38 cm
Handlebar Depth (mm)
70 mm
Handlebar Reach (mm)
120 mm

She was comfortable with this, so I said I would gather a list of bikes for her. It didn't take long to realize the options seem limited - she's wanting/needing a pretty sort reach (even after moving the saddle forward a bit - started using Dan's 10% back rule, but ended up moving her forward without having the knee extend past the pedal spindle), with quite a bit of stack. I'm going to double-check my measurements when I get back to the studio, but I'm pretty sure I didn't mess something up here as I was recording. I just realized I have not recorded the handlebar elevation or distance from the saddle to the hoods. I'll record those tonight.

The local bike shop had put her on a Felt ZW-85 for a test spin. She said it was a 54, although Felt's website uses "Petite (43)", "Small (45)", "Medium (47)" and "Tall (50)". Her comment, "it didn't feel very good, but I figured that was just because I don't know what I'm doing." She likes that particular bike, as it is close to her budget, but she's open to anything.

The small ZW-85 using the stock 70mm +17 deg stem, 10 mm of spacers, and 20 mm head set cap would put her at a stack of 613 and reach of 410. That's pretty stretched out.

The petite ZW-85 using the stock 60mm +17 deg stem, 20mm of spacers and 20 mm headset cap would put her at a stack of 598 and reach of 391. Still stretched out and a little low. - The ZW-85, specifically, is a little too long and low. There appear to be other options where the stack is more achievable (BMC Gran Fondo 48, Diamondback Airen 48).

This just doesn't seem right. I'd like to welcome a new member to the cycling community by getting her comfortable, but part of me thinks I have her closer to riding a beach cruiser than a road bike... The shortest bikes in the stack and reach database are still too long. This is what raises red flags for me. I feel like I've done something wrong here, or is this just a case of a very short torso with long legs making things difficult?

Any thoughts are greatly appreciated.

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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OK, just realized what I did. Stack was wrong - should be 405, not 375. I must have bumped the laser at some point and mismeasured.

I think that makes things a bit more realistic.

Thanks for any thoughts!

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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Travis R wrote:
OK, just realized what I did. Stack was wrong - should be 405, not 375. I must have bumped the laser at some point and mismeasured.

Stack? do you mean reach? That would help a lot for finding matching bikes
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Re: Does this seem right? [cyclenutnz] [ In reply to ]
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Doh! Thanks for catching that... Yes, I meant reach. got into too much of a hurry... Stack of 610, reach of 405.


cyclenutnz wrote:
Travis R wrote:
OK, just realized what I did. Stack was wrong - should be 405, not 375. I must have bumped the laser at some point and mismeasured.


Stack? do you mean reach? That would help a lot for finding matching bikes

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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Hello Travis,
Most helpful article: http://www.slowtwitch.com/..._Back_Lady_3609.html

This lady is very close to my size - inseam and torso, though a few inches taller than me. A few years older.
The 35cm shoulders seem a bit tiny for her size....is she 'slumping' her shoulders? How would you describe her posture? Overall physical condition?
What is her weight?

Using the ST Bar Bore calculator, and your HX/HY, I'm not getting the same numbers as you are; with my super secret spreadsheet and your saddle height numbers, I'm calculating her SX at 170 and her SY at 580. That would be perilously close to a 76deg seat angle at 653mm saddle height.

Be very careful about her seat angle - not the frame SA, but how far back she is from the BB. You note "15mm", is that correct? That would put her at a very steep position. A common adoption to rotate smaller riders to solve a reach issue, however, this would be at a loss of balance and function of the major muscle groups. For example, for my 30" inseam, I am 5cm behind the bb center (170 cranks). My saddle height is 660. I'm sitting at approx 75deg SA. You tipped your hand with the 'knee past pedal spindle' comment.

The stack and reach of the ZW bikes do not match up with the S/R that you have calculated. The Tall ZW85 has a reach of 382. A Cervelo S3 in 58cm has a Reach of 396. I'm confused about which bike you are measuring, with what stem/spacer combo. What is her reach, what is her stack, and what bike fits best up underneath her?

I ride a Cervelo S3 51cm with a 90cm stem at plus 6 with 30mm spacers.

longer rants about production bikes available for ladies like this and smaller are also available... haha. Also, Dan can testify how I led everyone into a trap at Down Deep in regards to seat-angle flummery. Similar to the Laid Back Lady, a novice rider can trick you into putting them in a 'bad' position...because they 'don't know what they're doing'.

Pictures would be awesome feel free to pm me. Happy to help out the nervous whores in any church!!

Anne Barnes
ABBikefit, Ltd
FIST/SICI/FIST DOWN DEEP
X/Y Coordinator
abbikefit@gmail.com
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Re: Does this seem right? [ABarnes] [ In reply to ]
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ABarnes wrote:
Hello Travis,
Most helpful article: http://www.slowtwitch.com/..._Back_Lady_3609.html

This lady is very close to my size - inseam and torso, though a few inches taller than me. A few years older.
The 35cm shoulders seem a bit tiny for her size....is she 'slumping' her shoulders? How would you describe her posture? Overall physical condition?
What is her weight?

First off, thank you so much for your thoughts on this. I really appreciate it!

Overall, posture is poor - shoulders are slumped and narrow, and she's overall pear-shaped, with poor muscle tone and poor flexibility. She's a long-time computer person with a desk job. She described herself as someone who has never been an athlete. She took up running only about two years ago, and achilles issues have forced her to spend some time with a PT and take a bit of time off from running. As she put it, the PT suggested she try doing some swimming or cycling while she was unable to run, so she opted for biking because "I royally suck at swimming."

ABarnes wrote:
Using the ST Bar Bore calculator, and your HX/HY, I'm not getting the same numbers as you are; with my super secret spreadsheet and your saddle height numbers, I'm calculating her SX at 170 and her SY at 580. That would be perilously close to a 76deg seat angle at 653mm saddle height.

Be very careful about her seat angle - not the frame SA, but how far back she is from the BB. You note "15mm", is that correct? That would put her at a very steep position. A common adoption to rotate smaller riders to solve a reach issue, however, this would be at a loss of balance and function of the major muscle groups. For example, for my 30" inseam, I am 5cm behind the bb center (170 cranks). My saddle height is 660. I'm sitting at approx 75deg SA. You tipped your hand with the 'knee past pedal spindle' comment.

Somewhere in here, I am starting to get lost, and this is where I get nervous (this is also why I am looking forward to doing F.I.S.T. in early 2016, as soon as Dan announces the next date after November...). My BikeFit training doesn't get into the geometry in nearly this much detail, so I'm dangerously self-taught here. With that said...

That 15mm is the correct net result, and that was concerning to me. I had started out using Dan's technique of setback at 10% of saddle height and a higher saddle height. This is where I'm a bit naive, too - I remember reading the Laid Back Lady article before and thinking, "well, 6 cm back doesn't sound too bad", so there are some details here I need to better understand. Among those, KOPS is another area I constantly question, although it is incorporated into BikeFit. In her case, I used it as a forward limit. Starting there, she surprised me in just how that was way too high for her, so we had to start shrinking things up immediately. Bringing the saddle down and forward eventually netted out to where we are, and as you say that seems to be a steep seat angle.

I hadn't yet done the math on the seat angle, but knew it was steep based on the 15mm setback. The Selle Royal Seta is 280mm long, so using trig and the center of the saddle, I get SX at 155, SY at 634 and SA ends up at 76.27 deg. Very steep. My calculations (especially SY) are quite a bit off of what you got with your supersecret spreadsheet. What did I do wrong here? I don't understand how you got the 170 and 580.

ABarnes wrote:
The stack and reach of the ZW bikes do not match up with the S/R that you have calculated. The Tall ZW85 has a reach of 382. A Cervelo S3 in 58cm has a Reach of 396. I'm confused about which bike you are measuring, with what stem/spacer combo. What is her reach, what is her stack, and what bike fits best up underneath her?

Using the specs from Felt's website, the petite comes with a +/-17 deg 60mm stem and the small comes with a +/-17 deg 70mm stem. They specify a 20mm headset cap and up to 20mm of spacers (thank you, Felt, for putting that info where somebody can actually find it). When her stack seemed a bit high, I calculated based on the +17 deg stem. Because she liked this bike, I made the mistake of trying to force it to happen, although I did tell her I would be giving her a list of better choices.

ABarnes wrote:
I ride a Cervelo S3 51cm with a 90cm stem at plus 6 with 30mm spacers.

longer rants about production bikes available for ladies like this and smaller are also available... haha. Also, Dan can testify how I led everyone into a trap at Down Deep in regards to seat-angle flummery. Similar to the Laid Back Lady, a novice rider can trick you into putting them in a 'bad' position...because they 'don't know what they're doing'.

Pictures would be awesome feel free to pm me. Happy to help out the nervous whores in any church!!

I hear you about the "longer rants about production bikes available for ladies like this and smaller". Having fit a few women in the 4' 11" to 5' 2" range who were sold 700c bikes by local shops, I consider myself very lucky to know that the cycling world revolves around me at 5' 11" and male. I definitely feel a bit "tricked" here - it's a battle between "the customer is always right"/what feels good and bike fit convention. I might be being a little too passive in this case. I worry that if we go with what feels good to her, we're going to be fighting numb fingers and other issues because the position isn't right. I've always been on the receiving end of problems - I don't want to be on the giving end!

Crazy question: With the longer reach after remeasuring, does this give us the ability to essentially slide her back on the horizontal plane (increase SX and decrease HX) to an appropriate seat angle without actually having her come back in?

Thank you again for all the thoughts!

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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If you decrease HX you will have more of a struggle to find a bike that fits.
But it is often possible to increase SX and leave HX thus increasing saddle-bars with no issue. I'd suggest looking at her Pelvic rotation - if she is rotating back the saddle is too far forward - if not, then she is one of the few that can handle a steep road saddle position. But it's more likely that she will end up supporting torso with hands instead of core when sitting that far forward.

As far as bike options for the position you've asked about



I set material as Aluminium to keep cost down, though I doubt the EM AFX will be in budget. Also, had tolerance set as 10mm, so would got with 60mm on the Fuji to narrow the tolerance


Last edited by: cyclenutnz: Aug 18, 15 3:00
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Re: Does this seem right? [cyclenutnz] [ In reply to ]
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Thanks for your thoughts, and the screen shot - I hope everything is going well on that end!

Her pelvic rotation actually looked good with the right saddle, with just a bit of downward tilt. Tilt it up a bit, and the back instantly rounded.

Part of me wonders if there's a bit of a psychological aspect with new cyclists, in that having some weight on the hands feels "good" because it feels like they have more control of the bike, without realizing the negative effects.

Thanks again for the help!
Travis

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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Oh, yes Travis there is a large pysch component to any rider, especially a newbie.

Michael Sylvester said it best: bike fitting is a trust exercise. Establish trust, maintain trust, ENtrust your knowledge to the rider.

This particular rider is coming to you saying she wants a road bike, but is ending up on a unicycle. Somewhere in there she is afraid...afraid of something....bending over? Hurting her grundle?

Forget all the numbers, laser beams, mechanical tools and big data. Listen to the rider, observe the rider. They will have a 'tell', it may not be verbal, but it's on you to get her into the middle of the bell curve of acceptability. ixnay on the outliers-ay.

This message brought to you by the Guild of the Black Arts of Bike Fitting :)

Anne Barnes
ABBikefit, Ltd
FIST/SICI/FIST DOWN DEEP
X/Y Coordinator
abbikefit@gmail.com
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Re: Does this seem right? [ABarnes] [ In reply to ]
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ABarnes wrote:
Oh, yes Travis there is a large pysch component to any rider, especially a newbie.

Michael Sylvester said it best: bike fitting is a trust exercise. Establish trust, maintain trust, ENtrust your knowledge to the rider.

This particular rider is coming to you saying she wants a road bike, but is ending up on a unicycle. Somewhere in there she is afraid...afraid of something....bending over? Hurting her grundle?

Forget all the numbers, laser beams, mechanical tools and big data. Listen to the rider, observe the rider. They will have a 'tell', it may not be verbal, but it's on you to get her into the middle of the bell curve of acceptability. ixnay on the outliers-ay.

This message brought to you by the Guild of the Black Arts of Bike Fitting :)

Well said - great thoughts all around! Part of me wants to change around one sentence: "saying she wants a beach cruiser, but was told she needs to be on a road bike." :)

This is a big step for her and I'm excited to help her with it. Sometimes, I think I err on the side of doing what the customer wants rather than telling them what they want. She'll be a work in progress, but I think she's going to be fine!

Thank you again for your help - I really appreciate it!

Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador
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Re: Does this seem right? [Travis R] [ In reply to ]
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Great info!
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Re: Does this seem right? [suttong] [ In reply to ]
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If you follow the protocall the saddle setback s/b at least 65mm 10%+1 = 75mm not 15mm. Taking the reach back to around 315. What is that saddle angle at 65.5 saddle height?

I think you have her too far forward. She is having to hold herself up with her hands and saddle instead of the pedals. Being too far forward also plants weight on the saddle and bars instead of the pedals. She needs to be bent over enough to load her core to transfer the weight to the pedals.

Redo the fit starting with a 73° saddle angle at the 65.5 height. (It's hard get a small bike saddle and bars back to 72° b/c of keeping a good stem length). The reach will come back to a norm and she will be way more comfortable b/c she can hold her weight up with the pedals.

I don't put women on WSD bikes because it puts them too far forward for the weight transfer to the pedals.
You should point out toe overlap on the small bikes with 73° seat tubes. At slow speeds the front tire will hit the toe when steering. Just teach her to corner with a foot down when going slow.

http://www.mybicyclefit.com
Last edited by: Geeios: Sep 6, 15 22:12
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