Sit Bone Width Relative to Optimal Saddle Selection

nutdriver

Member
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USA
I wanted to share my recent experience and insights about saddle selection after a disappointing first attempt at picking what I hoped would be a more comfortable option. I would be interested in hearing how this might relate to your own experiences. I am riding a Gazelle, Ultimate T10+ which has a slightly sporty “60 degree“ seating position. My sit bone measurement is 12 cm. Using the Ergon website saddle selector guidance, they recommended that I purchase a Large size Model “ST Core Evo.” After experimenting with different levels of saddle tilt, fore aft saddle position, and altering my reach with an adjustable bike handlebar stem, I have concluded that this is not going to work for me. I start experiencing saddle discomfort and perineal tingling after 10 miles, despite the center pressure relief channel in this saddle model.

Caliper set at 12 cm for my 12 cm sit bones. To my eye, my sit bone will be quite close to the seat edge.
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I decided to compare my sit bone measurement which is 12 cm to the actual size of this saddle. The first photo shows my caliper set to 12 cm and where that falls on my saddle. In the second photo, I have reset my caliper to 14 cm. The general recommendation is to add somewhere between 2 - 4 cm to the sit bone measurement depending on how upright or forward leaning the ride position is. In this case, I added 2 cm. The second photo shows just how close to the edges of my seat my sit bones are positioned.

Calipers set at 14 cm.
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The last photo shows a fairly typical seat profile which is somewhat convex relative to my butt. It strikes me that this saddle shape puts even more unnecessary pressure where it is not helpful.

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Curious if anyone else has made similar measurements and what your conclusions are.
 
You need to become aware that the "relaxed" (yours) or "upright" riding position will place the most of your body weight onto the saddle. Wide and thickly padded "comfortable seats" won't help at all. As I suffered for some years riding in the "relaxed" position using "comfortable saddles", I have completely changed my optics on the matter.

Using long stems on my both e-bikes, I could eventually assume a 45 degree riding position, and that puts some torso weight onto the bars. Manipulating the saddle fore/aft, I found the position that places another part of my body mass on the pedals. Finally, I started using narrow and firm saddles combined with chamois shorts or bibs. All my issues are gone. I can pedal for one hundred kilometres and even do not have a slightest thought of my butt. I do not necessarily ride with my sit-bones on the saddle, it varies over the ride. Sometimes I just sit on the saddle's nose.

I know my own experiences won't help you. You could try a narrower and firm saddle but the best way is to get used to it :)
 
You need to become aware that the "relaxed" (yours) or "upright" riding position will place the most of your body weight onto the saddle. Wide and thickly padded "comfortable seats" won't help at all. As I suffered for some years riding in the "relaxed" position using "comfortable saddles", I have completely changed my optics on the matter.

Using long stems on my both e-bikes, I could eventually assume a 45 degree riding position, and that puts some torso weight onto the bars. Manipulating the saddle fore/aft, I found the position that places another part of my body mass on the pedals. Finally, I started using narrow and firm saddles combined with chamois shorts or bibs. All my issues are gone. I can pedal for one hundred kilometres and even do not have a slightest thought of my butt. I do not necessarily ride with my sit-bones on the saddle, it varies over the ride. Sometimes I just sit on the saddle's nose.

I know my own experiences won't help you. You could try a narrower and firm saddle but the best way is to get used to it :)
I appreciate your input Stefan. It is all a very personal journey. For reference, I am about 6'2" and 185 lbs and will be 70 in another couple of months.

I have tried increasing my forward position to put more pressure on my hands (and less on my seat) but that also resulted in some nerve discomfort in my hands. I also had a rotator cuff repair in my shoulder this past January so my options to add even further pressure is limited somewhat by my recovery from that surgery. After considering some of the past discussions and partially at your recommendation, I did pick up a new pair of grips. That was just yesterday and have not installed those yet. I went with SQLab 702 which should help alleviate some pressure on my hands. If that goes well, I may also add the innerbarends at a later time.

Ultimately, it seems significant that having sit bones positioned almost off the seat is a factor that want to explore further but it does raise the question, that a wider seat may also increase chaffing. It strikes me that the industry needs to get more creative with seat design. SQLabs seems to have done that with their 702/710 grips and looking forward to using those. The grips seem to be a real game changer.

For many years, I rode a recumbent and miss the amazing comfort provided by that style of bike. The load on those bikes is mostly carried through seat and back. I now live in the mountains of Colorado, and recumbent bikes are not at their best in these conditions.
 
Measured my sit bone separation twice at 11 cm on center using the SQLab method, added 4 cm for my almost upright posture per their recommendation, and bought a 15 cm SQLab 602 M-D Active saddle.

The 602 eliminated the perineal pain I was having but added new tailbone pain. Plus too little lateral sit bone support as I pedaled and cornered. Not quite as close to the sides of the saddle as you showed but too close for me.

SQLab support (very helpful) recommended going to a 16 cm saddle with perineal AND tail bone cut-outs. So I tried the 16 cm 610 Ergolux Active 2.1.

Still not perfect, but the extra 1 cm width solved the lateral support issue, and my tail bone's a lot happier. Calling off the costly saddle search for now.

NB: If you buy an SQLab saddle directly from them, they'll take it back after a short trial as long as the cover's still like new, and the rails haven't been marred.
 
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Measured my sit bone separation twice at 11 cm on center using the SQLab method, added 4 cm for my almost upright posture per their recommendation, and bought a 15 cm SQLab 602 M-D Active saddle.

The 602 eliminated the perineal pain I was having but added new tailbone pain. Plus too little lateral sit bone support as I pedaled and cornered. Not quite as close to the sides of the saddle as you showed but too close for me.

SQLab support (very helpful) recommended going to a 16 cm saddle with perineal AND tail bone cut-outs. So I tried the 16 cm 610 Ergolux Active 2.1.

Still not perfect, but the extra 1 cm width solved the lateral support issue, and my tail bone's a lot happier. So calling off the costly saddle search for now.

NB: If you buy an SQLab saddle directly from them, they'll take it back after a short trial as long as the cover's still like new, and the rails haven't been marred.
Thanks for sharing your experience. I just looked at the SQLab 610 Ergolux Active 2.1. I see that they also make this in a 17 cm. I will give that some consideration.
 
People that run bike shops seem to be of the opinion that sitting down is some sort of chemical addiction. They sell mostly blades. I learned to ride in the days of the upright cruiser with a coaster brake, and prefer to sit up to avoid the risk of breaking a neck disk as my Mother did at work with a lunchroom table for a typewriter stand.
My ischea are about 11.5 cm apart.
In my mid sixties all the fat on my hips melted away, to match my bony old man's chin. Unfortunately this makes sitting on my bicycle a trial. Wide is good IMHO, however there needs to be some padding. I cannot try cloud9, the post of my bodaboda is a strange diameter. A seat has to fit the rails.
I found a highly recommended SQlab 621 M-D Active CrMo Rail 240 Saddle to be as hard as a brick. The rocking suspension was also a figment of their sales writer's imagination. It might rock if I weighed double my 160 lb. It was so painful I had to turn around at 10 minutes and go back home. Waste of $110.
Garbage was the wide schwinn seat from the grocery store. The leather of a used brooks from the charity resale shop did nothing for me. The selle royale respiro was tolerable only for rides of 2 hours. Pretty good was the 260x218 mm evo cruiser saddle, okay for 3 hours. A bargain at $32. I rode that for 2 years. Lastest trial is the $69 selle royale explora which seems to be good for 3.7 hours. Selle Royale Explora is about 232 mm wide, with almost adequate padding.
I do not know why vendors will not make a comfortable bicycle seat. The seat on my tinturi exercycle is extremely comfortable, with 2 cm of urethane padding. It is about 34 years old, and is holding up fine. Unfortunately it sits on a rectangular steel post.
Happy shopping and later riding.
 
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People that run bike shops seem to be of the opinion that sitting down is some sort of chemical addiction. They sell mostly blades. I learned to ride in the days of the upright cruiser with a coaster brake, and prefer to sit up to avoid the risk of breaking a neck disk as my Mother did at work with a lunchroom table for a typewriter stand.
My ischea are about 11.5 cm apart.
In my mid sixties all the fat on my hips melted away, to match my bony old man's chin. Unfortunately this makes sitting on my bicycle a trial. Wide is good IMHO, however there needs to be some padding. I cannot try cloud9, the post of my bodaboda is a strange diameter. A seat has to fit the rails.
I found a highly recommended SQlab 621 M-D Active CrMo Rail 240 Saddle to be as hard as a brick. The rocking suspension was also a figment of their sales writer's imagination. It might rock if I weighed double my 160 lb. It was so painful I had to turn around at 10 minutes and go back home. Waste of $110.
Garbage was the wide schwinn seat from the grocery store. The leather of a used brooks from the charity resale shop did nothing for me. The selle royale respiro was tolerable only for rides of 2 hours. Pretty good was the 260x218 mm evo cruiser saddle, okay for 3 hours. A bargain at $32. I rode that for 2 years. Lastest trial is the $69 selle royale explora which seems to be good for 3.7 hours. Selle Royale Explora is about 232 mm wide, with almost adequate padding.
I do not know why vendors will not make a comfortable bicycle seat. The seat on my tinturi exercycle is extremely comfortable, with 2 cm of urethane padding. It is about 34 years old, and is holding up fine. Unfortunately it sits on a rectangular steel post.
Happy shopping and later riding.
Thanks for your note. I am starting to share many of your conclusions.

A couple days ago, I returned the Ergon ST Core Evo seat to REI. Ergon claims that this model is good for up to 12-16 cm sit bones. No way would I agree with that. I am so thankful for the REI return policy and they took it back without complaint. This REI also had a nice selection of seats that I was interested in. After considerable pondering and measurements, I selected the Ergon ST Gel Men's Medium/Large version. The ST Gel is physically wider, and a bit softer. It was also considerably less expensive.

I do have it installed but rain and colder weather where I live has limited my ability to test this out. I will update again once I have a few miles on this saddle.
 
I'm using the 16cm SQLab 610 Ergolux Active 2.1 on one bike, and two others have the 610 Infinergy 2.1, which is a slight upgrade and much bigger bucks. I definitely prefer the Infinergy covering but if I buy another one it will be the Ergolux simply based on cost.

I used to use Ergon ST Core Primes and an ST Core MTB. and I ended up replacing three of them because I had made a bad judgment call on sizing. Actually, what I did worked but it had anatomical consequences. I went down to the small/medium size on bikes where I pedaled at high cadence because I thought it would work better for pedaling. And it does. But my ass suffered for it. The Ergon saddles seem to be better suited to more upright riding, whereas SQLab saddles come in models that handle more of a lean-over position, which is something Ergon seems to lack.


BEFORE: More upright position and Ergon ST Core Prime in Large size (click to embiggen).
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AFTER: Lower handlebars and the Ergon didn't fare well. Swapped in my 16 cm Ergolux from another bike and problem solved (except now I have a bike with no saddle on it). This pic was two days ago.
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Note the different top profiles of both saddles. The SQLab looks angled down but its not. Thats the ischial padding making it look that way. Nose of the saddle is parallel to the ground.
 
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