What makes a bike a "59?" Or a "58?" Or a "57?" Etc…

[flying]

Originally Posted by Clean39T

If it fits, you must sits.

.
..
.

I took a chance on a Canyon Ultimate CFR with wildly different geometry than anything I've had before - the reach figure is huge for an "XL", almost 420mm, where (for example) a 59.5 Dogma is around 390mm, and the STA is almost 74-deg vs. the 72.5-deg that is the norm for other bikes this size, at least historically. The Canyon has a 596mm TT and 1034mm WB w 70mm drop. And it fits beautifully. Instead of running a 120/130mm stem on a shorter front-center bike (shorter TT, less reach), the Canyon runs a 110mm stem. I used around 15mm setback and sit much further forward on the Canyon than I have on other bikes in recent years. I'm motoring on it. And I don't think it's just the 6.8-kg weight. Plus, it handles better than nearly any other bike I've ridden in recent years, which I chalk up more to how my weight is balanced on the bike than anything else. I don't get speedwobbles or a floaty front end, which has long been my bugaboo. Anyway, it was a step outside of the standard "62cm ST w 59cm TT and 72.5-STA" box I more or less lived in for years, and I love it. So much so that when I finally get a new custom done, I'll probably just ask to copy this geometry and be done with it.

That is very interesting to me especially as I run a lot of setback & have noted many companies switching to steeper STA's
Lately have been wondering about all of this too & asked Standert why even on their Steel frames they were running 74.5 STA on a 54

Their answer was
"we just tend to design our geometry a bit more modern and compact than traditional frames. It gives great handling on the front with a slightly longer stem for that sporty feel but with traditional appearance"

Which made no sense to me as setback & reach are two different things & lack of setback cannot be cured with more stem

So interesting to hear your impressions of the more forward position. Thanks

[robt57]

Originally Posted by flying

That is very interesting to me especially as I run a lot of setback & have noted many companies switching to steeper STA's

Which made no sense to me as setback & reach are two different things & lack of setback cannot be cured with more stem

So interesting to hear your impressions of the more forward position. Thanks

Which is why I used the term fore/aft fit window. And also to me fore/aft CG window. If your weight is out of it you will be doing nose wheelie upon braking or just closer to endos if too forward.

If too rearward, steering response suffers among other handling quirks. Like speed wobbles and shimmy shimmy coco bop et al.

The All Road and Gravel longer WB and CS have a bigger window than a RR geom. I wonder how many riders happen to get in the window on the longer geoms, when out of it on that Nago EP or other RR/geom for all time previously.

[NHAero]

There's a lot to integrate about fit. I feel I learned a lot from the fit I had on my previous custom. When I bought the Firefly from Ari, I got sucked in because it was such a beauty but I thought it was going to be too long in the TT at 549mm. It actually fits great. I pretty much duplicated the contact points of saddle setback, shifter hoods, and BB on the new Strong. Once the frame dimensions are understood, differences in bar shapes and shifter dimensions matter. Shimano shifters added 10mm of reach vs the Campy ones the Firefly came with. The saddle to center of bars dimension on the Strong is 10mm longer on the Strong than the Firefly, because the Zipp SL70 XPLOR bars have a back sweep that moves the hoods back relative to the stem. In the end, my saddle is in the same position relative to the BB and relative to the hoods on both bikes, even though they have some different measurements (FF STA is 73.2 vs 74 on the Strong, for example, but the saddle setback is the same on both bikes). The only exception is that right now the Strong has less bar drop because I had a 0 degree stem around instead of the -6 degree stem it was designed around, but the fit feels good so I haven't messed with it.

Originally Posted by flying

That is very interesting to me especially as I run a lot of setback & have noted many companies switching to steeper STA's
Lately have been wondering about all of this too & asked Standert why even on their Steel frames they were running 74.5 STA on a 54

Their answer was
"we just tend to design our geometry a bit more modern and compact than traditional frames. It gives great handling on the front with a slightly longer stem for that sporty feel but with traditional appearance"

Which made no sense to me as setback & reach are two different things & lack of setback cannot be cured with more stem

So interesting to hear your impressions of the more forward position. Thanks

[Kirk007]

Originally Posted by Clean39T

If it fits, you must sits.

.
..
.

I took a chance on a Canyon Ultimate CFR with wildly different geometry than anything I've had before - the reach figure is huge for an "XL", almost 420mm, where (for example) a 59.5 Dogma is around 390mm, and the STA is almost 74-deg vs. the 72.5-deg that is the norm for other bikes this size, at least historically. The Canyon has a 596mm TT and 1034mm WB w 70mm drop. And it fits beautifully. Instead of running a 120/130mm stem on a shorter front-center bike (shorter TT, less reach), the Canyon runs a 110mm stem. I used around 15mm setback and sit much further forward on the Canyon than I have on other bikes in recent years. I'm motoring on it. And I don't think it's just the 6.8-kg weight. Plus, it handles better than nearly any other bike I've ridden in recent years, which I chalk up more to how my weight is balanced on the bike than anything else. I don't get speedwobbles or a floaty front end, which has long been my bugaboo. Anyway, it was a step outside of the standard "62cm ST w 59cm TT and 72.5-STA" box I more or less lived in for years, and I love it. So much so that when I finally get a new custom done, I'll probably just ask to copy this geometry and be done with it.

I find this intriguing as well having just bought Dan's Kirk, which has a steeper seattube and longer front-center by a couple cms than all my other bikes. It will soon be for sale. I can make it fit, but it just doesn't work for me as well as a slacker seattube, shorter top tube and longer stem. I suspect weight distribution is the big factor here. The Kirk has a phenomenal ride, but for me, it's handling is merely good, not great, and I know I can have great.

[NHAero]

What's interesting to me about your experience here is that first and foremost you've changed your saddle setback, which is the point in space where most fitting begins. What happens if you duplicate that on your other bikes and use a longer stem to get the same reach?

Originally Posted by Clean39T

If it fits, you must sits.

.
..
.

I took a chance on a Canyon Ultimate CFR with wildly different geometry than anything I've had before - the reach figure is huge for an "XL", almost 420mm, where (for example) a 59.5 Dogma is around 390mm, and the STA is almost 74-deg vs. the 72.5-deg that is the norm for other bikes this size, at least historically. The Canyon has a 596mm TT and 1034mm WB w 70mm drop. And it fits beautifully. Instead of running a 120/130mm stem on a shorter front-center bike (shorter TT, less reach), the Canyon runs a 110mm stem. I used around 15mm setback and sit much further forward on the Canyon than I have on other bikes in recent years. I'm motoring on it. And I don't think it's just the 6.8-kg weight. Plus, it handles better than nearly any other bike I've ridden in recent years, which I chalk up more to how my weight is balanced on the bike than anything else. I don't get speedwobbles or a floaty front end, which has long been my bugaboo. Anyway, it was a step outside of the standard "62cm ST w 59cm TT and 72.5-STA" box I more or less lived in for years, and I love it. So much so that when I finally get a new custom done, I'll probably just ask to copy this geometry and be done with it.

[Kirk007]

Originally Posted by NHAero

What's interesting to me about your experience here is that first and foremost you've changed your saddle setback, which is the point in space where most fitting begins. What happens if you duplicate that on your other bikes and use a longer stem to get the same reach?

This reminds me of a statement from (I think) Davis Phinney when he first went to Europe and was counseled to switch to a frame with more setback for stage racing than the frames that he used in the US for mostly crit races. Different positions may well work for the same person depending on use and criteria.

[robt57]

Originally Posted by NHAero

What's interesting to me about your experience here is that first and foremost you've changed your saddle setback, which is the point in space where most fitting begins. What happens if you duplicate that on your other bikes and use a longer stem to get the same reach?

That seems a VG question, color me curious as well.


I just got done telling VoyTirando in eMail [bought my Ti Super] about once hitting a 1/2 mile with 4" of ground off pavement in middle or repaving.

In 2001 in full dweeb fashion the 6 rider group doing the yearly 180 miler was all on LiteSpeeds. Only my only LS was my TT Saber. I threw drop bars and moved the bar cons off the aero bar ends to the drop bars ends for the yearly 180 mile flyer.

Long Story Short, The long Front Center and WB had me flying across the moon surface waiting on the other side for the other riders walking the 1/2 mile. My 10 years of MotoCross may have had a little to do with it as well.

[Clean39T]

Originally Posted by flying

So interesting to hear your impressions of the more forward position. Thanks

My experienced stack/reach - i.e., the shape and proportion of the triangle between my hips, shoulders, and hands - always ends up being about the same regardless the size of the frame. What changes is where my COG/mass is between the wheels and where my hands and hips are. So, I can ride a 56cm Pegoretti with a 130 stem, or a 65cm "Freuler" Colnago Master Light with a 110 stem and have roughly the same "fit" as far as the shape of my body on the bike - but a much different handling experience.

What I really like about the Canyon is that in the XL size because the STA is steep, I don't feel like I'm hanging off the back even with a 15mm setback post. I feel like my weight is in the right place relative to the rear-wheel, even with chainstays that are "only" 415mm.. And because it has a long front center (wheelbase is 1034, which is longer than a Spesh Roubaix), I'm not cramped there and there's no toe-overlap, all while I'm still getting good weight on the front because my saddle is more forward.

I think some of this also has to do with the fact that I carry my extra weight in my thighs/hips, not my belly, and have a scrawny upper body. Which means that my COG/mass is already rearward biased when in a cycling position, relative to someone who may have scrawny legs, a bit of a mid-section, and more normal chest/arms - so, if I take that pre-determined rear-ward bias and add a "traditional" setback for my size, it leads to me being very unbalanced on the bike. I think this is why I've really struggled with handling on bikes with a shorter TT that I've compensated for by having a more rearward bias with a setback post and gaining reach with a longer stem - in that position, I simply don't have enough mass far enough forward to keep the front end from shimmying or being knocked off line by wind.

Or maybe I've just spun a yarn here and its really nothing more than confirmation-bias all the way down.

[robt57]

Originally Posted by Clean39T

And because it has a long front center (wheelbase is 1034, which is longer than a Spesh Roubaix),

Before they messed with the 1039 the SL4s had for the 61CM Roubaix that is.. The 58 SL4 S-Works Roubaix is 1029 FWIW.

I digress, but they shoulda let that be. Spesh needs to just make a RouMac or TarBaix and be done with it. Just saying...

Or maybe I've just spun a yarn here and its really nothing more than confirmation-bias all the way down.

I am sure I am not the only one here watching you jumping from 58-62s wondering where you'd find yourself.

[Clean39T]

Originally Posted by Kirk007

I find this intriguing as well having just bought Dan's Kirk, which has a steeper seattube and longer front-center by a couple cms than all my other bikes. It will soon be for sale. I can make it fit, but it just doesn't work for me as well as a slacker seattube, shorter top tube and longer stem. I suspect weight distribution is the big factor here. The Kirk has a phenomenal ride, but for me, it's handling is merely good, not great, and I know I can have great.

Does your Spectrum have a STA slacker than the Kirk? I figured they were both 72.5 w roughly the same chainstay lengths.. Have you tried the Kirk with a zero offset post and either dropping the stem a bit or putting the longer one on? I'd be curious on how that changed things for you, or if it did.

I rode it in many variations but I think my favorite was with a zero-SB post, a SMP Forma, and no spacers (can't remember if that was with a 120 or 130 on there). I'm also guilty though of always riding solo and hammering, so my desires and preferences for handling may vary from the norm quite heavily.

It's an exceptional bike and I'd hoped it'd work for you (so I could see it again from time to time if nothing else) but if it doesn't and it needs to find a new home, I'm sure it'll make someone else quite happy too.

[Clean39T]

Originally Posted by robt57

Before they messed with the 1039 the SL4s had for the 61CM Roubaix that is.. The 58 SL4 S-Works Roubaix is 1029 FWIW.

I digress, but they shoulda let that be. Spesh needs to just make a RouMac or TarBaix and be done with it. Just saying...

I'm close to trying a 2021 S-Works Roubaix for shigs n' giggs - but the stack on them is monstrous and has me a little spooked. I'm just curious how big of a difference the gizmos would make on long rides on imperfect pavement. But yeah, the new ones are an odd mashup of a Tarmac and an endurance bike - and somehow are still on the portly side (gizmos cost grams) even with top-tier spec.. I'll note that it has a 73.5 STA and roughly the same TT as the Canyon - just 5cm more stack!

[Dave]

Frame reach and overall reach is NOT affected by the STA. That's the beauty of refencing the center of the BB. The only thing that the STA does is affect your choice of saddle setback, as needed to place your body in the same position, relative to the BB. A frame with 74 degree STA might require 25mm more setback than one with a 72 degree STA, but if the frame reach is the same, the overall reach will be the same, using the same stem and bars.

Frame size numbers and letters are meaningless these days. Look at the stack, reach and STA. That should tell you if there will be fit problems. In a rare instance, a seat tube length could be too short for a 350mm post to have 100mm inside the frame.

My Cinelli superstar frames are called XS size. That means absolutely nothing other than it's the smallest size they offer - there's no XXS. With a 46cm seat tube, it's the shortest I've ever owned, but I could fit the smallest Atheos with a 43cm seat tube, too. It's actually got 5mm more stack height.

[mhespenheide]

Originally Posted by robt57

I will add that reach has to have STA accounted for your fit check list.

Reach of 'XX' on a 73^ STA VS 71.8^ where on the latter you will maybe/more likely use a zero offset seatpost negates a portion of the reach unless you are going to ride the frame with more saddle setback. If you aren't, you got a shorter reach than you thought you choose, effectively a shorter TT.

I think of it as the fore/aft fit window on the bike, being I always start with saddle setback.

I will be sitting in said fore/aft window, even if at the front or rear edge of it. I think of this as fore/aft CG window most importantly, being my girth in said window will effect balance rolling 100%.

While I agree with you on the idea of a fore-aft window and setback, reach explicitly does not need to account for seat tube angle. Reach is measured horizontally, the distance from the bottom bracket forwards to the headset. Reach was invented so that the change in the top tube length relative to a changing seat tube angle is taken out of the calculation. Reach should be equal after setback is set equal.

(But reach does change with head tube angle and head tube length...)

[robt57]

Originally Posted by Clean39T

I'm close to trying a 2021 S-Works Roubaix for shigs n' giggs - but the stack on them is monstrous and has me a little spooked. I'm just curious how big of a difference the gizmos would make on long rides on imperfect pavement. But yeah, the new ones are an odd mashup of a Tarmac and an endurance bike - and somehow are still on the portly side (gizmos cost grams) even with top-tier spec.. I'll note that it has a 73.5 STA and roughly the same TT as the Canyon - just 5cm more stack!

Future shock too shocking for me. ;O

Even the SL4 stack for the 61 is nose bleed, now bigger?. I am glad Spesh 58s works for me. Even so I am trying a slammed -12 temeyone sold me that is inbound. The new RouMac 61 has a stack of 665mm, OMG. If you are 6'7" maybe.

You could spy a Flatforce stem to make it tenable maybe?

[robt57]

Originally Posted by mhespenheide

While I agree with you on the idea of a fore-aft window and setback, reach explicitly does not need to account for seat tube angle.

The reason I disagree is where the TT winds up in the window. For me the slack STA means zero offset post, and shorter EFF TT rolling.

Which is OK if longer reach bars/stem for the cockpit I'd need does not move me too forward in the window. Which it has always seemed to. But I got longish femurs, could be why compared to normal proportioned rider/position.