Frame size, new bike fitting, questions

Back by popular demand, the general all-things Road forum!

Moderator: robbosmans

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

by toshi

forklifter wrote:
Mon Jan 16, 2023 9:02 am

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?
Hey Forklifter, again I'm no expert but I know enough to know there are lots of variables :lol: . Also, only you know your body. My non-expert interpretation of your videos is —
  • Something seems to cause your pelvis to lose stability on your Astra. My non-expert opinion is your more closed hip angle on the Astra reduces pelvic stability on that bike. I suppose your crank length could be a contributor but your stack and reach numbers (at contact points) are worth a look too.
  • (In my recent experience, when my pelvis is not stable, my upper body is not as relaxed because it has to try and compensate for that lack of stability. Then I lose power, because there is energy from that effort to stabilize things.) You might be more upright on the R5, but if you produce more power being slightly more upright because you are more stable, is it a bad thing? Maybe, maybe not. If you're more aero, maybe it compensates for whatever loss in power you experience.
  • I suggested reducing reach, because I think it's an easy way to reduce your hip angle while leaving everything else the same — including your saddle setback, which I assume is identical between Astra + Cervelo.
  • Earlier, you said you thought your position was better on the Astra. My question: can you more comfortably put out more power on the Astra, or the Cervelo? What about at the end of a long ride, or at the end of several weeks of long rides? From the videos, you seem more stable on the Cervelo, so my assumption (big assumption!) is you can produce more power with less effort on the R5, even though you sit a little more upright on the R5
  • To say it another way: your pedaling + position on the R5 looks more effortless. It looks easier and more relaxed on that bike, compared to on the Astra.
So you would stay with 56? For this then a shorter stem?
I think your position on the R5 looks great. I was suggesting a shorter stem on the Astra. Hopefully some other people can share their insights! :beerchug:

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



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

by toshi

PS: interesting conversation on pelvic stability and how it affects on-bike functionality + power: https://podcasts.apple.com/us/podcast/e ... 0469501513

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

by forklifter

toshi wrote:
Tue Jan 17, 2023 2:16 am
forklifter wrote:
Mon Jan 16, 2023 9:02 am

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?
Hey Forklifter, again I'm no expert but I know enough to know there are lots of variables :lol: . Also, only you know your body. My non-expert interpretation of your videos is —
  • Something seems to cause your pelvis to lose stability on your Astra. My non-expert opinion is your more closed hip angle on the Astra reduces pelvic stability on that bike. I suppose your crank length could be a contributor but your stack and reach numbers (at contact points) are worth a look too.
  • (In my recent experience, when my pelvis is not stable, my upper body is not as relaxed because it has to try and compensate for that lack of stability. Then I lose power, because there is energy from that effort to stabilize things.) You might be more upright on the R5, but if you produce more power being slightly more upright because you are more stable, is it a bad thing? Maybe, maybe not. If you're more aero, maybe it compensates for whatever loss in power you experience.
  • I suggested reducing reach, because I think it's an easy way to reduce your hip angle while leaving everything else the same — including your saddle setback, which I assume is identical between Astra + Cervelo.
  • Earlier, you said you thought your position was better on the Astra. My question: can you more comfortably put out more power on the Astra, or the Cervelo? What about at the end of a long ride, or at the end of several weeks of long rides? From the videos, you seem more stable on the Cervelo, so my assumption (big assumption!) is you can produce more power with less effort on the R5, even though you sit a little more upright on the R5
  • To say it another way: your pedaling + position on the R5 looks more effortless. It looks easier and more relaxed on that bike, compared to on the Astra.
So you would stay with 56? For this then a shorter stem?
I think your position on the R5 looks great. I was suggesting a shorter stem on the Astra. Hopefully some other people can share their insights! :beerchug:

Hey toshi, thanks for your effort and the long text you wrote.

I might have to mention that I am struggling with a crooked pelvis. The left side is lower than the right. However, the left leg is about 2cm shorter than the right when I hold my legs side by side while lying or sitting. The pelvis is twisted in on itself and also slightly tilted forward.

I have also thought about cleat stackers for the left foot.
I just made a bargain with 165mm long cranks. I'll try that too, so I can open the hip angle a little.

Thanks also for the podcast tip. I have already listened to 4 different episodes. Super interesting.

thirdsun
Posts: 422
Joined: Fri Aug 06, 2021 3:20 pm

by thirdsun

I’m looking for a new endurance bike for long days in the saddle, bike packing trips and everyday commuting. It should be compact and rather low (for an endurance bike, or relaxed for a race bike). I like my endurance bikes racy (my main bike is an Aeroad CF SLX). However I’m having a hard time finding suitable geometries. I measure 165 cm in height with an inseam of 75 cm.

My old Canyon Endurace CF SL 9 in 2XS is close to my ideal geometry - short and rather low: https://www.canyon.com/en-de/road-bikes ... &history=1

These are the candidates I currently have on my shortlist:

- Look 765 Optimum (XS): https://www.lookcycle.com/de-en/product ... -satin-105 - couldn’t find any information on the weight but the geometry looks fine with a few spacers removed. My local dealer would also change crank length to 165 mm free of charge. Midguard mounts, tidy cable management under the stem, this seems like a very reasonable bike.


- Canyon Endurace CF 7 Di2 (2XS): https://www.canyon.com/en-de/road-bikes ... be=BK%2FBK - Great spec, excellent procing, decent weight once I replace the wheels, 165 mm cranks, narrow handlebars included. Unfortunately 650B wheels in 2XS. I need to find out if it can fit 700C. Otherwise it’s out. I won’t buy a bike with 650B wheels - there aren't any tire options. Looking at the reach+ and stack+ values it’s rather close to my old Endurace.


- Basso Astra 105 Di2 (2023) (45 or 48): https://bassobikes.com/en/bikes/road-bikes/astra - Again no information on weight, looks like a solid option. Sizes 45 and 48 look very similar with the latter featuring a slightly longer top and seat tube. Does anyone have any recommendations on sizing here?

Any thoughts on my shortlist?

Does anyone have any other recommended candidates I might have missed?

I also considered the Cervelo Caledonia but while the geometry seems great this thing is downright heavy. I don’t like paying premium for what seems like a very average bike.
  • Canyon Aeroad CF SLX 8 Di2
  • Cervelo Caledonia Rival eTap AXS
  • Vitus Venon Evo
  • Canyon Grail CF SL 8 Di2

TobinHatesYou
Posts: 13039
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

thirdsun wrote:
Wed Feb 01, 2023 1:48 pm
I’m looking for a new endurance bike for long days in the saddle, bike packing trips and everyday commuting. It should be compact and rather low (for an endurance bike, or relaxed for a race bike). I like my endurance bikes racy (my main bike is an Aeroad CF SLX). However I’m having a hard time finding suitable geometries. I measure 165 cm in height with an inseam of 75 cm.
Go here: https://www.bike-stats.de/en/geometrie_filtern

Select 28”
Enter your desired ranges for reach and stack.
It won’t have a complete list of bikes, but certainly easier than combing through all the different product pages.

thirdsun
Posts: 422
Joined: Fri Aug 06, 2021 3:20 pm

by thirdsun

TobinHatesYou wrote:
Thu Feb 02, 2023 12:37 am
thirdsun wrote:
Wed Feb 01, 2023 1:48 pm
I’m looking for a new endurance bike for long days in the saddle, bike packing trips and everyday commuting. It should be compact and rather low (for an endurance bike, or relaxed for a race bike). I like my endurance bikes racy (my main bike is an Aeroad CF SLX). However I’m having a hard time finding suitable geometries. I measure 165 cm in height with an inseam of 75 cm.
Go here: https://www.bike-stats.de/en/geometrie_filtern

Select 28”
Enter your desired ranges for reach and stack.
It won’t have a complete list of bikes, but certainly easier than combing through all the different product pages.
Thank you. Yes, I'm aware of bike-stats.de and already used it. Well, I took another look and added the Fara F/AR to my shortlist. Interesting bike but sadly little independent information on it.
  • Canyon Aeroad CF SLX 8 Di2
  • Cervelo Caledonia Rival eTap AXS
  • Vitus Venon Evo
  • Canyon Grail CF SL 8 Di2

RoadDonk82
Posts: 82
Joined: Wed Feb 08, 2023 2:43 pm

by RoadDonk82

I am trying to find out if Aethos 49 is going to be suitable for my girlfriend. She is 165cm with longer legs. Her saddle height is 68.5cm, tip of the saddle to handlebar reach 45cm, saddle setback 30mm (with Specialized Power saddle). Saddle to bar drop: 50mm. Those are numbers from a bikefitting session she had some time ago but we are not sure if that's the best position for her and are experimenting with a current bike. It would be nice if there is room to make a saddle setback a bit bigger and a saddle/handlebar drop a bit less if needed. Specialized sizing chart says 52 is her size but it just seems too big with the above mentioned numbers. Anyone around that height with an insight about 49cm frame? Is it going to force a huge saddle to handlebar drop with her saddle height?

thirdsun
Posts: 422
Joined: Fri Aug 06, 2021 3:20 pm

by thirdsun

RoadDonk82 wrote:
Thu Mar 09, 2023 10:35 pm
I am trying to find out if Aethos 49 is going to be suitable for my girlfriend. She is 165cm with longer legs. Her saddle height is 68.5cm, tip of the saddle to handlebar reach 45cm, saddle setback 30mm (with Specialized Power saddle). Saddle to bar drop: 50mm. Those are numbers from a bikefitting session she had some time ago but we are not sure if that's the best position for her and are experimenting with a current bike. It would be nice if there is room to make a saddle setback a bit bigger and a saddle/handlebar drop a bit less if needed. Specialized sizing chart says 52 is her size but it just seems too big with the above mentioned numbers. Anyone around that height with an insight about 49cm frame? Is it going to force a huge saddle to handlebar drop with her saddle height?
I have never ridden an Aethos. However I'm 165 cm with a 75 cm inseam and might be able to add something.

Right, according to Specialized I should ride a size 52, which is surely wrong. The reach is just way too long and I can't imagine your girlfriend would be happy with that size. Even size 49 seems close to the limit of what I could comfortably ride. I own an Canyon Aeroad and an Endurace. The Aeroad is slightly shorter in reach (372) but lower than the Aethos. The Endurace is close to my optimal geometry with a reach of 360 and a stack 510. Both bikes are fine and the Aethos in size 49 would probably work as well but it really shouldn't be any longer. Your girlfriend seems to have a shorter upper body than me - size 49 might work for her too. Size 52 seems out of reach for the both of us.
  • Canyon Aeroad CF SLX 8 Di2
  • Cervelo Caledonia Rival eTap AXS
  • Vitus Venon Evo
  • Canyon Grail CF SL 8 Di2

DaveS
Posts: 3940
Joined: Fri Mar 24, 2006 1:26 pm
Location: Loveland Colorado

by DaveS

Compare the stack and reach of the Atheos to your current bike. A lot depends on your desired saddle to bar drop. I'm taller at 168cm with a 72.5cm saddle height, but the 49 has enough stack for me, because I use an 11.5cm saddle to bar drop. The 75.5 degree STA is too steep, IMO. The reach is also plenty long. If I bought one, I'd get the 52 and slam it with a -17 x 100mm stem. For a smaller rider, I'd look for less reach and no more than a 74.5 degree STA. Stack would depend on the saddle to bar drop.

RoadDonk82
Posts: 82
Joined: Wed Feb 08, 2023 2:43 pm

by RoadDonk82

Right, according to Specialized I should ride a size 52, which is surely wrong. The reach is just way too long and I can't imagine your girlfriend would be happy with that size. Even size 49 seems close to the limit of what I could comfortably ride. I own an Canyon Aeroad and an Endurace.
Thank you for your insight. I thought about Endurace (for both of us actually, I am a bit taller with much longer upper body) but decisions Canyon made for the current models rule it out (smaller wheels is one but integrated cockpit is another, we don't have dialed in fit yet and integrated cockpit is just a huge problem if you want to adjust something).
The 75.5 degree STA is too steep, IMO. The reach is also plenty long. If I bought one, I'd get the 52 and slam it with a -17 x 100mm stem. For a smaller rider, I'd look for less reach and no more than a 74.5 degree STA. Stack would depend on the saddle to bar drop.
This is a good point about STA angle. I missed it. The current bike (kinda random bike tbh) has STA of 73 degrees and the seat is rather forward so maybe it's still ok with much steeper STA. I will need to do some math on it as getting to measure anything (let alone test ride) here is rather hard. When it comes to Aethos size 52 I think it will be perfect for me (171cm, short legs) but surely too long for my GF.
There aren't that many bikes out there which don't have too many proprietary components, are easy to live with when travelling and suit shorter rider with longer legs. Another candidate is Liv Langma which in size S seems to be between Aethos 52 and 49.

thirdsun
Posts: 422
Joined: Fri Aug 06, 2021 3:20 pm

by thirdsun

RoadDonk82 wrote:
Sun Mar 12, 2023 4:32 pm
Thank you for your insight. I thought about Endurace (for both of us actually, I am a bit taller with much longer upper body) but decisions Canyon made for the current models rule it out (smaller wheels is one but integrated cockpit is another, we don't have dialed in fit yet and integrated cockpit is just a huge problem if you want to adjust something).
Thanks for mentioning the 650B wheels Canyon decided to use on most 3XS and 2XS models. I've been complaining to anyone who's willing to listen. As much as I like Canyon and the value of their bikes 650B wheels are an absolute dealbreaker. I understand that they might be necessary for 3XS but there's little excuse to design the 2XS around them. They used to ship that size with 700C. Slightly better handling isn't worth having to rely on such a limited selection of tires...or wheelsets should want to change them.
  • Canyon Aeroad CF SLX 8 Di2
  • Cervelo Caledonia Rival eTap AXS
  • Vitus Venon Evo
  • Canyon Grail CF SL 8 Di2

RoadDonk82
Posts: 82
Joined: Wed Feb 08, 2023 2:43 pm

by RoadDonk82

They used to ship that size with 700C. Slightly better handling isn't worth having to rely on such a limited selection of tires...or wheelsets should want to change them.
It seems to me their strategy is to sell to people who like the whole package and won't change anything. In this context it makes sense to make the best bike they think they can make. For me integrated cockpits are even worse than small wheels. You can still get get Conti's gp5000 for those wheels in both 25 and 28 but if you need to change the stem or bar width you are out of luck (only a few combinations available on their website, god knows how long it takes to ship and if you need some other combination there is nothing you can do, they are also like 350-400E a piece). If something breaks when travelling you will be stuck without a bike because of cheap piece of plastic no one has stocked locally.

I agree that wheels make things more difficult as well. You will always need to have your supply of tubes, spokes and tires as no one will have those to share/sell to you if needed.

thirdsun
Posts: 422
Joined: Fri Aug 06, 2021 3:20 pm

by thirdsun

RoadDonk82 wrote:
Sun Mar 12, 2023 6:21 pm
You can still get get Conti's gp5000 for those wheels in both 25 and 28
Not if you want to ride tubeless. The GP 5000 S TR in 650B only starts at 30 mm.

In 28 mm / tubeless / 650B you're down to the Schwalbe Pro One. In other words you're one discontinued product away from not having a suitable tire for your bike.
  • Canyon Aeroad CF SLX 8 Di2
  • Cervelo Caledonia Rival eTap AXS
  • Vitus Venon Evo
  • Canyon Grail CF SL 8 Di2

User avatar
bomber
Posts: 260
Joined: Tue May 29, 2007 8:53 pm
Location: L'Australie

by bomber

In need of advice before I make a possible costly mistake. I'm updating bikes mid year and the new bike in the same size is slightly shorter in reach (5mm) but more crucially higher in stack (10mm) putting in between two sizes coming from my old bike.

Am I better to size down, starting with 5-8mm more spacers with a longer stem (110mm vs 100mm) to achieve the same fit? Sizing down would give me better standover clearance as well.
Carb loading since the 90's


My ex ride
My old rides

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

www.starbike.com



tourniquet
Posts: 16
Joined: Fri Dec 20, 2019 11:33 pm

by tourniquet

Hey, I need a new bike frame and I was wondering if you have some ideas.

Background:
In 2018 I bought a Hongfu FM008 in Size 50 and built my first real road bike. I'm 170cm tall (short, lol) and have 81cm inseam (relatively long legs for being short).
In order to look cool I cut the steerer (too) short and now the geometry is just too agressive for my body dimensions. Can't really ride in the drops.

Yes, the FM008 is sometimes marketed as an Endurance frame, but in the small sizes the headtube is rather short... maybe the linear scaling of stack and reach throughout the sizes is not that good... but that's another topic.

long story short: Either I buy handlebars with +2cm rise (meh) or I swap the frame.

Any recommendations for a small rim brake frame with relaxed geometry that doesn't look super ugly?
  • I am open to open mold as well as western brands.
  • 28mm tire clearance would be cool (the FM008 even struggles with 25mm)
  • Standard 27mm seatpost would be cool (because I need 0 offset)
Geometry-wise the Emonda ALR with H2 geometry seems like something that could suit me, but it's alloy, relatively expensive, the sloping in small sizes looks extreme, and requires Direct Mount Brakes.

Post Reply