Frame size, new bike fitting, questions

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TobinHatesYou
Posts: 12456
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

toshi wrote:
Sun Jan 23, 2022 12:01 am
I'm currently on a 51cm Ritchey Road Logic (geo), and going to a 52cm Factor o2 (geo):
  • • Stack is identical across these bikes, but the Factor has 11mm less reach.
  • • The Ritchey has a 74.5° STA, the Factor = 73° STA.
:?: On the Ritchey, I run a 20mm stem. Would I run a 130mm stem (same angle) on the Factor o2, after adjusting for saddle setback? Thanks!

Your saddle X/Y is relative to the BB and shouldn't change just because you move to a bike with a different STA. You'd simply move the saddle along its rails and/or switch between a setback seatpost or a zero setback one.

The same goes for your bar X/Y. You are aiming to achieve the same position relative to the BB. Since the Factor has less reach at the same stack, If you use a longer -6deg stem, it will actually make the Factor "bar stack" a few millimeters higher than the Ritchey at the equivalent "bar reach." If you're running 10mm in spacers on the Ritchey, then I would run 5mm in spacers on the Factor with the longer stem.

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toshi
Posts: 268
Joined: Tue Jul 04, 2006 1:32 am

by toshi

Thanks Tobin. Exactly — so, taking into account what you said, let me ask another way: assuming I replicate saddle position relative to BB on the Factor, does my stem lengthen, or shorten, on the Factor?

Edit: reading your reply once more, it seems you're alluding to a longer stem, since you mention reducing headset height. 8)

TobinHatesYou
Posts: 12456
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

toshi wrote:
Sun Jan 23, 2022 2:35 am
Thanks Tobin. Exactly — so, taking into account what you said, let me ask another way: assuming I replicate saddle position relative to BB on the Factor, does my stem lengthen, or shorten, on the Factor?

Edit: reading your reply once more, it seems you're alluding to a longer stem, since you mention reducing headset height. 8)

If you use a 10mm longer -6deg stem on a bike with a 73deg HTA, the bar stack will increase by about 2mm. I said reduce the spacer stack by 5mm, but really it's more like 3mm for roughly the same fit. Either way it's not a whole lot and you will probably be fine being within +/-5mm in any direction.

paulpongco
Posts: 24
Joined: Wed Sep 16, 2020 1:59 am

by paulpongco

osw000 wrote:
Fri Jan 21, 2022 1:26 pm
paulpongco wrote:
Thu Jan 20, 2022 7:23 am
I have the 2020 Venge at size 56. I was professionally fitted with the current configuration at 100mm -6 deg stem and zero spacers under the stem (except for the required upper and lower transition caps which I think would be adding roughly 15mm).

I am considering getting an Aethos and am on the fence if I should stick with 56 or size down to a 54.

Comparing Stack and Reach
Venge 56: Stack 555 Reach 398
Aethos 54: Stack 544 Reach 384 (11mm lower and 14mm shorter)
Aethos 56: Stack 565 Reach 395 (10mm higher and 3mm shorter)

My height is 182.6cm and inseam of 86.6.

Based on the stack and reach, it seems that I can make the Aethos 54 with 110mm stem and 10mm spacer (or 20mm if I take the transition caps into consideration). Is it that simple to map or am I missing anything?

My seat post height in the venge is 71cm so this can be accommodated by the Aethos 54.

Appreciate feedback.

Thanks.
If you have been fitted properly, and measured the seat height correctly, with a such a low 71cm seat height for your height, I would say that either because of poor flexibility or extreme seatback you will be ok with an smaller size.
Thanks..on my previous Giant TCR, seat height was at 75cm..the low seat height of 71cm took time for me to adapt my feels better..i am not that flexible but this slow seat height on the venge seems to be allowing for downsizing to a 54 on the aethos...

Roadbiker10
Posts: 495
Joined: Fri Apr 30, 2021 8:22 am

by Roadbiker10

To replicate the fit exactly as my previous bike, I would need another cm longer stem, on my Addict RC. The stack is the same. I have a couple of months until I start riding the bike. What I would like to know is, if I go with 1cm shorter reach, how much lower does my stack need to be to kind of replicate the torso angle? Is it possible to calculate this?

How much would these changes affect hydraulic cable length? Like 1cm longer or lower, would that require longer/shorter cables?

The bike is going to the shop soon for a handlebar change. Going from 42 to 38. So they will need to shorten the cables, but is it possible to leave a bit more cable length in case I decide to switch to a 120mm stem. Right now I have a 110mm.
Scott Addict RC 20 2021
Ridley Kanzo Adventure 2022

Roadbiker10
Posts: 495
Joined: Fri Apr 30, 2021 8:22 am

by Roadbiker10

Just curious. What saddle height are people running respective to their inseam? I have an idea that mine is low but I'm not sure. My inseam is about 86cm. I'm 180-182cm tall. Right now I'm running 75,5cm. On my bikefit they set it at 76cm, but I have had some issues with tight hamstring on my right side when in an aero position. So I lowered it a little amd tilted the saddle forward a bit. I'm not sure though if that's what caused it.

I have had many issues all on my right side. Knee, foot, glute and hamstring.
Scott Addict RC 20 2021
Ridley Kanzo Adventure 2022

gorkypl
Posts: 529
Joined: Fri Sep 21, 2018 9:31 am
Location: Poland

by gorkypl

Roadbiker10 wrote:
Tue Jan 25, 2022 8:20 pm
Just curious. What saddle height are people running respective to their inseam? I have an idea that mine is low but I'm not sure. My inseam is about 86cm. I'm 180-182cm tall.
For your height inseam minus 9 cm is a common starting point. I'm 182cm, 88cm inseam, and have 79cm saddle height.

Fuji Cross 1.5 - Shimano 105 5800 | Cinelli Superstar Disc - Record 12s | Custom steel Karamba - Ekar 13s

TobinHatesYou
Posts: 12456
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

It turns out everyone is slightly different. 178cm tall, 815mm inseam. 714mm saddle height, 66mm setback (with a 240mm saddle,) 165mm cranks, EU44.5 feet. I am also hyperflexible in all the right places and require an extra long reach.

mikethewhite
Posts: 3
Joined: Wed Feb 02, 2022 5:17 am

by mikethewhite

Hey everyone, looking for a gut check on a Pinarello Dogma F size.

Height: 178.5cm
Inseam 83.5cm
Saddle: 74cm

I currently mostly ride a 56 Cervelo C3, with a 120m -17 stem, 74cm saddle. Have made a few modifications to make the geometry less endurnace-y (new fork with different rake, etc.), but it's still an endurance frame and there is no escaping that, it's fun for long relaxed rides on crappy roads but not very exciting. I also wish it was a 54, which is part of what I am looking to solve here.

For the F I've been recommended 3 sizes: 530, 540, and 550. The 550 seems like it will just be too large, so I am leaning towards 530 and 540, but wanted the feedback from some smarter people on this forum.

survivor
Posts: 557
Joined: Tue Apr 28, 2015 5:08 pm

by survivor

mikethewhite wrote:
Wed Feb 02, 2022 5:26 pm
Hey everyone, looking for a gut check on a Pinarello Dogma F size.

Height: 178.5cm
Inseam 83.5cm
Saddle: 74cm

I currently mostly ride a 56 Cervelo C3, with a 120m -17 stem, 74cm saddle. Have made a few modifications to make the geometry less endurnace-y (new fork with different rake, etc.), but it's still an endurance frame and there is no escaping that, it's fun for long relaxed rides on crappy roads but not very exciting. I also wish it was a 54, which is part of what I am looking to solve here.

For the F I've been recommended 3 sizes: 530, 540, and 550. The 550 seems like it will just be too large, so I am leaning towards 530 and 540, but wanted the feedback from some smarter people on this forum.
If you have not already, I would recommend checking out velogitfit. Their web tool has a pretty comprehensive comparison between your current bike setup to the potential new setup.

https://www.velogicfit.com/frame-comparison/

TobinHatesYou
Posts: 12456
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

mikethewhite wrote:
Wed Feb 02, 2022 5:26 pm
Hey everyone, looking for a gut check on a Pinarello Dogma F size.

Height: 178.5cm
Inseam 83.5cm
Saddle: 74cm

I currently mostly ride a 56 Cervelo C3, with a 120m -17 stem, 74cm saddle. Have made a few modifications to make the geometry less endurnace-y (new fork with different rake, etc.), but it's still an endurance frame and there is no escaping that, it's fun for long relaxed rides on crappy roads but not very exciting. I also wish it was a 54, which is part of what I am looking to solve here.

For the F I've been recommended 3 sizes: 530, 540, and 550. The 550 seems like it will just be too large, so I am leaning towards 530 and 540, but wanted the feedback from some smarter people on this forum.

Are you slammed on the C3?

If you go with the "55cm" you might be between a 100mm or 110mm/-6deg bar/stem, nearly slammed.

If you go with the "54cm" you might still need to drop down to the 110mm stem, but you have room for spacers.

I do not think the "53cm" would be a good option unless you want to go significantly lower than your current setup.

mikethewhite
Posts: 3
Joined: Wed Feb 02, 2022 5:17 am

by mikethewhite

TobinHatesYou wrote:
Fri Feb 04, 2022 2:37 am
mikethewhite wrote:
Wed Feb 02, 2022 5:26 pm
Hey everyone, looking for a gut check on a Pinarello Dogma F size.

Height: 178.5cm
Inseam 83.5cm
Saddle: 74cm

I currently mostly ride a 56 Cervelo C3, with a 120m -17 stem, 74cm saddle. Have made a few modifications to make the geometry less endurnace-y (new fork with different rake, etc.), but it's still an endurance frame and there is no escaping that, it's fun for long relaxed rides on crappy roads but not very exciting. I also wish it was a 54, which is part of what I am looking to solve here.

For the F I've been recommended 3 sizes: 530, 540, and 550. The 550 seems like it will just be too large, so I am leaning towards 530 and 540, but wanted the feedback from some smarter people on this forum.

Are you slammed on the C3?

If you go with the "55cm" you might be between a 100mm or 110mm/-6deg bar/stem, nearly slammed.

If you go with the "54cm" you might still need to drop down to the 110mm stem, but you have room for spacers.

I do not think the "53cm" would be a good option unless you want to go significantly lower than your current setup.
I am slammed on the C3. I don't think going lower is too huge an huge issue as the C3 geometry is overly relaxed, which is why I have -17 degrees on there now.

TobinHatesYou
Posts: 12456
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

mikethewhite wrote:
Fri Feb 04, 2022 8:36 pm

I am slammed on the C3. I don't think going lower is too huge an huge issue as the C3 geometry is overly relaxed, which is why I have -17 degrees on there now.

Either the 54cm or 53cm then. Depends whether you want to slam the 54cm or maybe have a 1cm spacer on the 53cm, both with. -6deg stems.

dsk28
Posts: 50
Joined: Mon Jan 04, 2021 8:10 am

by dsk28

mendieta wrote:
Thu Jun 10, 2021 12:20 pm
Im 166,5 cm, inseam 78 cm, saddle height 68,3 cm and got offer for Pinarello Dogma F10 size 50. Anyone here with my height what size Dogma do you have ? Maybe i should find 46.5 size as it has shorter top tube 51.5 cm)
I'm 175cm with 82cm inseam and I ride the 51.5
I think you're better off with the 46.5, better get a bike fit or try test riding the size 50 (if possible)

*wrong reply to an earlier post - mod pls delete
Last edited by dsk28 on Sun Feb 20, 2022 2:42 am, edited 1 time in total.

dsk28
Posts: 50
Joined: Mon Jan 04, 2021 8:10 am

by dsk28

mikethewhite wrote:
Wed Feb 02, 2022 5:26 pm
Hey everyone, looking for a gut check on a Pinarello Dogma F size.

Height: 178.5cm
Inseam 83.5cm
Saddle: 74cm

I currently mostly ride a 56 Cervelo C3, with a 120m -17 stem, 74cm saddle. Have made a few modifications to make the geometry less endurnace-y (new fork with different rake, etc.), but it's still an endurance frame and there is no escaping that, it's fun for long relaxed rides on crappy roads but not very exciting. I also wish it was a 54, which is part of what I am looking to solve here.

For the F I've been recommended 3 sizes: 530, 540, and 550. The 550 seems like it will just be too large, so I am leaning towards 530 and 540, but wanted the feedback from some smarter people on this forum.
I'm riding on the 515 Dogma F with my height & inseam:

Height: 175cm
Inseam 82cm
Saddle: 72cm

I feel you would do good on the 530. For reference I usually ride a size 54 on other bikes.

by Weenie


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Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

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