DIY Sit Bone Measurement
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DIY Sit Bone Measurement
Anyone have a good method on measuring your sit bones at home? Looking to get a new saddle and just not sure what size I should get. Generally I'd guess I want the most narrow, but I'm just unsure.
Thanks!
Thanks!
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If you have hard bench, and a piece of corrugated cardboard, sit on it while hunching forward as you would on the bike. Don't wear padded shorts. Measure between the centers of the depressions.
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Helps to pull up on the bench or chair surface so that you actually dent the cardboard with your bones.
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Also helps to pull your knees up to your chest which makes the sit bones more prominent.
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I fell for the ass-o-meter, measure your sitz bones theory for finding a comfortable saddle at one time. That was a big fail for me. The most comfortable saddles for me had no correlation at all to the distance between my pelvic bone prominences. In fact, it wasn't even close.
In my opinion, you can't find a comfortable saddle with a ruler. Unfortunate, it is all trial and error. Ebay ended up being my best friend allowing me to try and resell 6-7 different saddles before I found the one that I have now used for 15-20 years.
In my opinion, you can't find a comfortable saddle with a ruler. Unfortunate, it is all trial and error. Ebay ended up being my best friend allowing me to try and resell 6-7 different saddles before I found the one that I have now used for 15-20 years.
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There's the sheet of tinfoil on a stair step method. Kind of a variation of the cardboard method, but I find it makes a more defined ass-print! I don't find this measurement massively useful, but gives some idea of where you "sit" in the overall range. Like if you find that you have much wider than average sit-bones, then a narrow saddle is probably not going to work. But if you have narrow sit-bones, you might still find that you prefer a wider saddle.
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I fell for the ass-o-meter, measure your sitz bones theory for finding a comfortable saddle at one time. That was a big fail for me. The most comfortable saddles for me had no correlation at all to the distance between my pelvic bone prominences. In fact, it wasn't even close.
In my opinion, you can't find a comfortable saddle with a ruler. Unfortunate, it is all trial and error. Ebay ended up being my best friend allowing me to try and resell 6-7 different saddles before I found the one that I have now used for 15-20 years.
In my opinion, you can't find a comfortable saddle with a ruler. Unfortunate, it is all trial and error. Ebay ended up being my best friend allowing me to try and resell 6-7 different saddles before I found the one that I have now used for 15-20 years.
To measure my seat bone distance, I touch each one with the corresponding index finger and asked my wife to measure the distance between my index fingers.
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Yeah I know all butts are different and the sit bones aren't a silver bullet. Just figured it was a decent place to start. Thanks for the tip about ebay though! That's a great idea.
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There's one important thing to realize in fitting a saddle based on "sit bone" width. In this drawing the "sit bones" are labeled "ischial tuberosity." The problem for road cyclists is that one only sits on the sit bones when in an upright riding position and any semi-aggressive posture rotates the rider's weight forward onto the pubic rami, which rapidly narrow. On my bikes, it's basically impossible to weight the sit bones for more than a few seconds while resting.
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A lot of saddles have gone through my shop over the years for me, family and friends. I am with jrobe on this, while my sit bones have not moved my saddles have shifted over the years. Now in my 70s with bars rising my saddles have shifted again and I prefer suspended leather saddles for the first time.
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there's one important thing to realize in fitting a saddle based on "sit bone" width. In this drawing the "sit bones" are labeled "ischial tuberosity." the problem for road cyclists is that one only sits on the sit bones when in an upright riding position and any semi-aggressive posture rotates the rider's weight forward onto the pubic rami, which rapidly narrow. On my bikes, it's basically impossible to weight the sit bones for more than a few seconds while resting.
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There's the sheet of tinfoil on a stair step method. Kind of a variation of the cardboard method, but I find it makes a more defined ass-print! I don't find this measurement massively useful, but gives some idea of where you "sit" in the overall range. Like if you find that you have much wider than average sit-bones, then a narrow saddle is probably not going to work. But if you have narrow sit-bones, you might still find that you prefer a wider saddle.
I agree its just a basic guide and can be very helpful. I purchased my first saddle off this method but wasn't 100% there. Then got a bike fitting and that was a great process and that was the "ah ha" moment for my cycling comfort.
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There's one important thing to realize in fitting a saddle based on "sit bone" width. In this drawing the "sit bones" are labeled "ischial tuberosity." The problem for road cyclists is that one only sits on the sit bones when in an upright riding position and any semi-aggressive posture rotates the rider's weight forward onto the pubic rami, which rapidly narrow. On my bikes, it's basically impossible to weight the sit bones for more than a few seconds while resting.
But I do think that riding posture has more influence on saddle choice than sit bone width and some saddle manufacturers do seem to design their saddles around riding posture, with width as a secondary option e.g. Fizik
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Very good point, but would that not be taken into account by saddle manufacturers in respect of their various width options - sit bone width being merely a convenient reference point? If somebody has narrow sit bones, then it follows that their pubic rami would also be narrow relative to someone with wider sit bones.
But I do think that riding posture has more influence on saddle choice than sit bone width and some saddle manufacturers do seem to design their saddles around riding posture, with width as a secondary option e.g. Fizik
But I do think that riding posture has more influence on saddle choice than sit bone width and some saddle manufacturers do seem to design their saddles around riding posture, with width as a secondary option e.g. Fizik
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DANG, guess there's no more office photo copy machine any longer.
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Thanks so much for the info! I've been using a cheap WTB saddle on my gravel bike and I'm good doing about 50 miles on that. But I've been battling saddle sores with it and I've got a road bike on the way so I want to make sure I can do longer rides more consistently. I'm not racing anyone, so I'm usually in a more upright position but it's still good to know about the taper you mentioned.
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Probably more important than width, unless you're far outside the norm, is shape. I'm pretty inflexible, can't reach beyond mid calf when trying to touch my toes (it's not age, I've never been able to), so I'm most comfortable on "wave" saddles that allow me to rotate my pelvis forward.
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Very good point, but would that not be taken into account by saddle manufacturers in respect of their various width options - sit bone width being merely a convenient reference point? If somebody has narrow sit bones, then it follows that their pubic rami would also be narrow relative to someone with wider sit bones.
But I do think that riding posture has more influence on saddle choice than sit bone width and some saddle manufacturers do seem to design their saddles around riding posture, with width as a secondary option e.g. Fizik
But I do think that riding posture has more influence on saddle choice than sit bone width and some saddle manufacturers do seem to design their saddles around riding posture, with width as a secondary option e.g. Fizik