Frame size, new bike fitting, questions

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calicyclist
Posts: 103
Joined: Fri Dec 02, 2022 5:54 am

by calicyclist

I am on a size 55 Dogma F10. In response to my queries, they've offered an options on a -3.5° which would put the bars 13mm lower or a flat stem which would be 11mm lower. This is why I am planning to mess around with my current setup and see if that really makes a difference in terms of comfort. What in particular about -6° makes that ideal? Argonaut has ability to do lots of frame customization but this is what fits into their "proven geometries" which means I don't have to wait an entire year for the build.
Argonaut RM3 | Pivot Trail 429

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

calicyclist wrote:
Tue Dec 13, 2022 4:35 pm
I am on a size 55 Dogma F10. In response to my queries, they've offered an options on a -3.5° which would put the bars 13mm lower or a flat stem which would be 11mm lower. This is why I am planning to mess around with my current setup and see if that really makes a difference in terms of comfort. What in particular about -6° makes that ideal? Argonaut has ability to do lots of frame customization but this is what fits into their "proven geometries" which means I don't have to wait an entire year for the build.

-6 to -10 is just what I consider aesthetically pleasing with modern sloped TTs.

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pwhee
Posts: 7
Joined: Fri Aug 05, 2022 10:17 am

by pwhee

I'm looking for size advise and opinions. My heigt is 1.87 cm with an inseam of 89.5 cm. My saddle height is somewhere between 78 - 79 cm. I used to sit at 79,5 cm but have been lowering my saddle after a hip injury. I further reduced my setback from approx 9 cm to 8 cm opening my hip and because this felt better after changing to a boost saddle (248 mm).

I've been riding size L Giant TCR's for some years but never felt right on the new geometry of my '21 TCR pro. A short test drive before purchasing this bike on a size ML instantly felt to small. So I went for the L and have been questioning this descision ever since.

I've put my bike fit on both L (58) and ML (56). What would you pick? 58 with a slammed stem or 56 with a couple more spacers and longer stem?

91F1EFFF-458A-4D2B-9A56-849AF0C580EF.jpeg
6742EE07-9BE7-403F-AE6D-71DC2C745DF0.jpeg

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

I would probably go with the M/L if the seatpost is long enough…

Jaisen
Posts: 676
Joined: Fri Oct 07, 2022 2:01 am

by Jaisen

Hi guys, I have a new Tarmac SL7. I transfered my fit from my previous bike onto it. The current fit feels great with no issues, but I noticed I still have a lot of room for further adjustability on the SL7 unlike on my old frame where it was slammed. I am currently using the stock -20mm offset saddle post that the SL7 came with. I am wondering what adjustments should be made if for example, I wanted to slam the saddle forward by using a 0 offset saddle post? All else equal should I increase the stem length/reach by the same 20mm amount to compensate? I have quite a few spacers left still under my stem, and am rather flexible, so I was curious to try lowering my front end. Rather than buying and testing many different stem lengths/angles, I am trying to get a gadge of how the adjustment of one component might effect the other. If I move the saddle forward, do I need to also change the saddle height and angle?

For example, in case it is relevant, the current saddle sits at 805mm with a -2% angle. My stem is 110mm, and I currently have a 20mm stack of spacers. The SL7 is a 58cm.

It is my understanding that as one slides the saddle forward, one can usually accommodate a lower front end (though sometimes this also requires longer stems and shorter cranks?)

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Jaisen wrote:
Thu Jan 12, 2023 11:35 am

It is my understanding that as one slides the saddle forward, one can usually accommodate a lower front end (though sometimes this also requires longer stems and shorter cranks?)
If you move your saddle forward, you’ll also want to move it up. That will naturally increase your saddle-bar drop so I wouldn’t lower your bars. You would want a longer stem though.

Jaisen
Posts: 676
Joined: Fri Oct 07, 2022 2:01 am

by Jaisen

TobinHatesYou wrote:
Thu Jan 12, 2023 12:56 pm
Jaisen wrote:
Thu Jan 12, 2023 11:35 am

It is my understanding that as one slides the saddle forward, one can usually accommodate a lower front end (though sometimes this also requires longer stems and shorter cranks?)
If you move your saddle forward, you’ll also want to move it up. That will naturally increase your saddle-bar drop so I wouldn’t lower your bars. You would want a longer stem though.
Sounds good, thanks for the reply. Would you add the same length to the stem as you moved the saddle forward? Perhaps my best bet would be to just buy a bunch of cheap stems of different lengths though and test it on the trainer before buying a new OEM stem replacement. Also is there a general rule of thumb by how much to increase the saddle for each 10mm it is moved forward?

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

Jaisen wrote:
Thu Jan 12, 2023 3:51 pm

Sounds good, thanks for the reply. Would you add the same length to the stem as you moved the saddle forward? Perhaps my best bet would be to just buy a bunch of cheap stems of different lengths though and test it on the trainer before buying a new OEM stem replacement. Also is there a general rule of thumb by how much to increase the saddle for each 10mm it is moved forward?

For stem length, you’ll more or less want to go 1:1.

For saddle height, it’ll depend on too many variables including your femur length, ankling, cleat position and starting saddle position.

Jaisen
Posts: 676
Joined: Fri Oct 07, 2022 2:01 am

by Jaisen

TobinHatesYou wrote:
Thu Jan 12, 2023 4:04 pm
Jaisen wrote:
Thu Jan 12, 2023 3:51 pm

Sounds good, thanks for the reply. Would you add the same length to the stem as you moved the saddle forward? Perhaps my best bet would be to just buy a bunch of cheap stems of different lengths though and test it on the trainer before buying a new OEM stem replacement. Also is there a general rule of thumb by how much to increase the saddle for each 10mm it is moved forward?

For stem length, you’ll more or less want to go 1:1.

For saddle height, it’ll depend on too many variables including your femur length, ankling, cleat position and starting saddle position.
Sounds good, I'll try the good old fashioned trial and error methods then for the saddle adjustments, and at least I know I can fall back to my current position if I can't get a more optimal position. Cheers.

forklifter
Posts: 108
Joined: Fri Dec 31, 2021 10:13 am

by forklifter

Hello, some fitting / sizing advices gladly requested.

Height: 180cm / 5.9 ft
Inseam: 90cm / 2,95 ft
Long legs, short torso

Last summer I found a very good fit on a Basso Astra in size 53 combined with 100mm stem in -7 degree and 70mm reach handlebar.
This bike will stay for long time. Only in aero position my hips starting to block a litte bit.

Now I built up a R5 from 2012 with Sram Red, tubulars and all the good stuff. This is size 56. No spacers. 70mm reach handlebar. 100mm stem -8 degree.

Personally, I think my position on the Basso Astra is better. I sit very upright on the R5. And a -12 degree 90mm stem is not what I am looking for.
Gained some weight and lost some fitness after Covid, maybe this is part of it. But maybe a 54 in Cervelos range would fit better.

What do you think about it? Opinions highly welcomed.
Attachments
Astra 53.png
Astra 53.png (719.34 KiB) Viewed 5840 times
R5 56.png
R5 56.png (704.27 KiB) Viewed 5840 times

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

forklifter wrote:
Sun Jan 15, 2023 1:03 pm
Hello, some fitting / sizing advices gladly requested.

Height: 180cm / 5.9 ft
Inseam: 90cm / 2,95 ft
Long legs, short torso

Last summer I found a very good fit on a Basso Astra in size 53 combined with 100mm stem in -7 degree and 70mm reach handlebar.
This bike will stay for long time. Only in aero position my hips starting to block a litte bit.

Now I built up a R5 from 2012 with Sram Red, tubulars and all the good stuff. This is size 56. No spacers. 70mm reach handlebar. 100mm stem -8 degree.

Personally, I think my position on the Basso Astra is better. I sit very upright on the R5. And a -12 degree 90mm stem is not what I am looking for.
Gained some weight and lost some fitness after Covid, maybe this is part of it. But maybe a 54 in Cervelos range would fit better.

What do you think about it? Opinions highly welcomed.

Your back is at almost the exact same height but your arm position is slightly more outstretched and maybe 1cm higher on the R5. Your shoulders are dropped a couple cm on the Basso and look more relaxed. Are both bars the same width at the hoods?

Either way, your back angle is quite aggressive in both shots, but I agree the slight differences on the Basso pass the eye test better. Would be better if there were 15 seconds of video for each though.

forklifter
Posts: 108
Joined: Fri Dec 31, 2021 10:13 am

by forklifter

TobinHatesYou wrote:
Sun Jan 15, 2023 4:59 pm
forklifter wrote:
Sun Jan 15, 2023 1:03 pm
Hello, some fitting / sizing advices gladly requested.

Height: 180cm / 5.9 ft
Inseam: 90cm / 2,95 ft
Long legs, short torso

Last summer I found a very good fit on a Basso Astra in size 53 combined with 100mm stem in -7 degree and 70mm reach handlebar.
This bike will stay for long time. Only in aero position my hips starting to block a litte bit.

Now I built up a R5 from 2012 with Sram Red, tubulars and all the good stuff. This is size 56. No spacers. 70mm reach handlebar. 100mm stem -8 degree.

Personally, I think my position on the Basso Astra is better. I sit very upright on the R5. And a -12 degree 90mm stem is not what I am looking for.
Gained some weight and lost some fitness after Covid, maybe this is part of it. But maybe a 54 in Cervelos range would fit better.

What do you think about it? Opinions highly welcomed.

Your back is at almost the exact same height but your arm position is slightly more outstretched and maybe 1cm higher on the R5. Your shoulders are dropped a couple cm on the Basso and look more relaxed. Are both bars the same width at the hoods?

Either way, your back angle is quite aggressive in both shots, but I agree the slight differences on the Basso pass the eye test better. Would be better if there were 15 seconds of video for each though.
Yes both handlebars are 38cm with slighty inward turned hoods.

Here you go:
R5: https://youtu.be/iaciV2oFm4I
Astra: https://youtu.be/eD3SUA3ctgw

TobinHatesYou
Posts: 13038
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

forklifter wrote:
Sun Jan 15, 2023 5:55 pm

Yes both handlebars are 38cm with slighty inward turned hoods.

Here you go:
R5: https://youtu.be/iaciV2oFm4I
Astra: https://youtu.be/eD3SUA3ctgw

Heh interesting. In the videos it almost looks like the 56cm R5 is the better fit in the sphinx/bent-elbow position. Interested to hear others' thoughts.

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

by toshi

I'm not a fitter, but having experienced something similar recently, you look much more stable on the R5. It's subtle, but I can see less pelvic stability when you pedal on the Astra... more lumbar triangle movement. From my uninformed opinion, your reach is 10mm too long on the Astra.

by Weenie


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forklifter
Posts: 108
Joined: Fri Dec 31, 2021 10:13 am

by forklifter

toshi wrote:
Sun Jan 15, 2023 8:27 pm
I'm not a fitter, but having experienced something similar recently, you look much more stable on the R5. It's subtle, but I can see less pelvic stability when you pedal on the Astra... more lumbar triangle movement. From my uninformed opinion, your reach is 10mm too long on the Astra.
TobinHatesYou wrote:
Sun Jan 15, 2023 8:07 pm
forklifter wrote:
Sun Jan 15, 2023 5:55 pm

Yes both handlebars are 38cm with slighty inward turned hoods.

Here you go:
R5: https://youtu.be/iaciV2oFm4I
Astra: https://youtu.be/eD3SUA3ctgw

Heh interesting. In the videos it almost looks like the 56cm R5 is the better fit in the sphinx/bent-elbow position. Interested to hear others' thoughts.
Thank you guys.
I think the height of the 56 R5 (580mm Stack) is generally a good thing for me. In reasons of reach and a standard bike setup I would say the bike might looks too long when set up for me like in the video.

toshi the slightly more movement seems right. Didnt recognized that first. Maybe because of 2,5mm shorter cranks on the R5 but same saddle height like on the Astra?

So you would stay with 56? For this then a shorter stem?

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