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Best sitbone measurement done at home

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Best sitbone measurement done at home

Old 05-08-19, 08:19 PM
  #1  
acorn54
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Best sitbone measurement done at home

while experimenting sizing my sit bones for a brooks on my bike, i came up with an idea that i'll pass along. the image one gets is remarkably similar to what i have seen
on the internet in x-ray images.:

light coat shaving foam on toilet seat cover

without undergarments on, of course sit on shaving foam.

the resultant image easily defines the sit bone structure for you to measure.
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Old 05-08-19, 09:53 PM
  #2  
texbiker
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Years ago I wrote this on my blog:
Saddles are a very personal fit item. If you are like me this is probably the bicyclist’s equivalent of the search for the Holy Grail. To me the important part is getting the seat cushion part to line up with my sit-bones. How do you do this? My thought is to take a piece of rather soft styrofoam about 3/4″ thick as a template to capture your sit-bone size, position and width. Here is how to do it:

* place the foam on a hard surface where you can sit as you would on your bike
* sit on the foam, being sure to make the sit-bones produce an impression into the foam
* now you can get fancy if you like, make a plaster-of-Paris casting of the impression
* take this casting or sheet of foam with you when inspecting saddles at your bike shop to compare your position versus the saddle positions.
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Old 05-08-19, 10:32 PM
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Bmach
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You are making it to complex. Just go to a bike shop and have them measure it. When you decide on a correctly fitted saddle ride it for a couple of hundred miles let your butt get used to it. I think to many people do not give their body time to adjust the a saddle before changing it out for another. Then the body has to adjust to another saddle and the cycle starts all over again. Just 2 cents worth.
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Old 05-09-19, 05:29 AM
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What do you do with the sit bone measurements when you have them? I have never measured my sit bones, but I have ridden a lot of different saddles and have not personally observed much correlation between saddle width and comfort.
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Old 05-09-19, 06:57 AM
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USN
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i just bought a foam cover at walmart and bought the riding shorts with the foam in them, Im good.
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Old 05-09-19, 11:01 AM
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Iride01
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Originally Posted by USN View Post
i just bought a foam cover at walmart and bought the riding shorts with the foam in them, Im good.
Let us know how that works after a four hour ride. If you are only doing a 20 minute ride, I'm sure it's quite comfy.

Oh.... welcome to the forums. You gotta take the flak... It's forum life.
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Old 05-09-19, 11:18 AM
  #7  
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I too have noticed little correlation between measurement and published saddle width. But for sure, don't get too narrow a saddle. I don't know the formula but it's probably something like add 40mm to measured width.
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Old 05-09-19, 12:22 PM
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sheet of foam core and a wooden chair? lay down the foam core-paper piece and sit on it. ?
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Old 05-09-19, 09:36 PM
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Originally Posted by USN View Post
i just bought a foam cover at walmart and bought the riding shorts with the foam in them, Im good.
No, actually, not being mean, you are not good. Piling foam on foam is not going to be comfortable. Just the opposite.

I have sat on the newspaper in my Speedo (or sans Speedo as the case might be) and gotten my sit bone number. I purchased my Specialized (Avatar) saddles using that number and am very pleased with the results. I have a somewhat wider than average (for a male) sit bone width, fairly wide. No, I am not fat, 5-10+, 29 inch waist and 154 pounds. The point being for many perhaps it does not matter but for a person who is outside of the norm for their gender, it could make a big difference.

Last edited by Loose Chain; 05-09-19 at 09:40 PM.
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Old 05-10-19, 01:38 PM
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Fill a large 1 or 2 gallon ziplock baggie with enough flour to make a thin flour mat after you evacuate all the air from the bag. Place it on a toilet lid and sit down slowly and carefully whilst bending forward into an aero posture. You should get two very distinct points where the bones jut out.
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Old 05-10-19, 03:58 PM
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Talking

Maybe someone should sell some casting kits tailor made for getting an impression of our butt. We could then take the mold and make an actual casting of our buts. Then we could take them with us to the LBS and see with our own eyes how we fit to a potential new purchase. <grin>

Not certain if I'm serious or jesting. Maybe both.
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Old 05-10-19, 05:57 PM
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I've used aluminum foil and a semi-firm cushion (ottoman or wide couch arm) with good results. Checked against measurements from an actual site bone measuring device it all matched up.
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Old 05-15-19, 09:21 AM
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My mom always does the measuring for me.
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Old 05-20-19, 12:55 PM
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Short rides only, maybe 2 to 10 miles with some rest stops, yep my bottom is ok,,,no long rides for us, mostly weekend warriors, simple stuff..
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Old 07-03-19, 04:20 PM
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If your home printer has a copy function make the copy of your butt. Just don't post here. On the other hand, it you are kinky, think of the image as wall art.
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Old 07-24-19, 09:03 PM
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Originally Posted by The_Joe View Post
I've used aluminum foil and a semi-firm cushion (ottoman or wide couch arm) with good results. Checked against measurements from an actual site bone measuring device it all matched up.
I used this method but with the foil on a carpeted stair in my house. It worked amazingly well. I had no idea what my sit bones looked like...
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Old 08-07-19, 02:23 PM
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Originally Posted by TXBDan View Post
I used this method but with the foil on a carpeted stair in my house. It worked amazingly well. I had no idea what my sit bones looked like...
Me too, it worked great. You have to make sure you get a perfectly unrumpled piece of foil, you can't yank it off and tear it on the built in cutter. You have to carefully unroll it and cut it with scissors. I got 115 but my left is slightly aft of my right. Do you measure in a straight line between them if they're off axis or extend a line and measure the actual lateral difference, which is going to be a tad shorter.
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