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Zelda_K
06-28-2010, 08:57 PM
this may be a stupid question: but how do you measure the distance between your sit bones? is there a good and easy technique to do this?

rubywagon
06-29-2010, 05:07 AM
Fill a one or two gallon ziploc with flour (not crammed full). Place it on a hard kitchen chair. Sit on the bag and lean forward, with a straight back until your elbows touch your knees. You can put your feet on a stool to elevate them a bit as well. Your sit bones should leave an indent in the flour. It works with play-doh too, apparently. :)

OakLeaf
06-29-2010, 05:29 AM
I highly recommend making a tracing. The simplest way to do this is to make your butt-print on a piece of paper to begin with (you will still have to outline the indentations, since the indentations will fade with time), but you can trace the indentations on whatever else you use, also. With a tracing, you have a permanent, portable record of the size and shape of your sitbones that you can lay over any saddle.

Gowest
06-29-2010, 05:34 AM
This is nuts - but it works! Find some SECLUDED pavement (like your patio) - take a piece of white paper (like you would put in a copier) - get naked and sit on the paper. Voila - you will see your sit bones on the paper - and you can measure the distance. just be discreet!!

Trek420
06-29-2010, 05:54 AM
Just do what I did: sit nekid on the company xerox machine. ;) You get a picture you can take with you to the LBS and ... ;) Just kidding, TE. Seriously you can also use a close and trusted friend and a tape measure. :) Just don't walk up to complete strangers with the tape measure. :)

Gowest
06-29-2010, 06:10 AM
I like the sit on the copier idea - then you can even shrink it down without diet and exercise!!!! hmmmmmm

Trek420
06-29-2010, 07:02 AM
Yes, but I think your sit bones have nothing to do with weight or height or .... :) You can have wide sit bones with narrow hips or vice versa. :cool: It's just bones. :cool: Just like you can be tall with small feet or short with big feet .... it's just bones.

Trek420
06-29-2010, 10:06 AM
Oooh, and with Play dough you could use newsprint instead of aluminum foil. That way you get the sit bones measurment on the Sunday Funnies. ;) Just kidding.

PamNY
06-29-2010, 10:58 AM
Here's a recipe for edible chocolate Play Doh (http://www.instructables.com/id/edible-chocolate-play-dough/).

rubywagon
06-29-2010, 11:14 AM
Haha! Oh that is clever. A play-doh you can measure your butt with, and then eat. How versatile.

OakLeaf
06-29-2010, 11:42 AM
Yuk! :eek: :p

pinkbikes
06-29-2010, 03:13 PM
I used the yoga mat method. Put a yoga mat on the bottom or second bottom step of some (preferably wooden) stairs. Sit on it. After a few minutes your sit bones will leave an imprint in the mat. Measure it.

No cooking required!:)

No eating required!:eek:

PS: Don't wear your knicks -the padding distorts the result. Naked would probably be best but only if the stairs are inside!:o And if it's a thin mat - fold it a couple of thicknesses to speed up the result.

pinkbikes
06-29-2010, 03:16 PM
this may be a stupid question: but how do you measure the distance between your sit bones? is there a good and easy technique to do this?

And so Zelda - do you notice any difference in comfort between your two different widths of Ariel seats? I also have the 143 (came on my Era) and absolutely love it but am unsure whether it is predominantly the width or shape that does it for me and how transferable that is to another Spesh seat.

I'm not as happy with the seats I have on my roadies and would like to try a Jett or similar but am reluctant to shell out the dollars if it is going to be a disaster.

macski
06-29-2010, 04:00 PM
Or you could go into your LBS - they will have some special memory foam that is designed to measure your sit bones as well as a size chart about what that means ;)

Chicken Little
06-29-2010, 04:03 PM
I think you need a CT scan to do this right. I tried all of the suggestions mentioned above, and came up with this obscure measurement that matched a giraffe pelvis in the third trimester.

Maybe the bike shop is the best source.

Catrin
06-29-2010, 04:09 PM
Not all bike shops have the memory foam, or agree with it...

PamNY
06-29-2010, 06:07 PM
Not all bike shops have the memory foam, or agree with it...

Don't agree with it -- meaning they don't think it gives an accurate or usable measurement?

I had great results with the yoga mat method, but that could just be luck.

tiva
06-30-2010, 11:31 AM
It's a great question! I've tried sitting on wet paper (bad idea) and then sitting on dry paper with a ballpoint pen in my hand, trying to trace (worse idea--my husband was really puzzled by how I ended up with ink all over my bottom). Playdoh, a bag of flour, or the yoga mat never occurred to me!

malkin
06-30-2010, 12:48 PM
How do you measure any other part of your body?

Use a cloth (or plastic) measure. Use one hand to hold the 0 end on one butt point and use the other hand to pinch the part of the tape over your other butt point.

KnottedYet
06-30-2010, 01:34 PM
I think you need a CT scan to do this right. I tried all of the suggestions mentioned above, and came up with this obscure measurement that matched a giraffe pelvis in the third trimester.



If you got the same measurement again and again with all the suggested methods, maybe you just have sitbones that match a giraffe pelvis in the third trimester?

(mine are 170-190mm, and my hips themselves are not very wide. Sit bone width and hip width don't have much to do with each other)

DebbieOSablada
06-30-2010, 03:50 PM
ahhhh.. i wonder if painting my butt lightly with my daughter's washable paints, and then sitting on paper (a la stamping) will work... :rolleyes:

GLC1968
06-30-2010, 04:08 PM
How do you measure any other part of your body?

Use a cloth (or plastic) measure. Use one hand to hold the 0 end on one butt point and use the other hand to pinch the part of the tape over your other butt point.

Ditto this.

Hold a fabric measuring tape in one hand. Lie on your back and flip your legs into the air (kind of over your head but you don't need to go that far). Feel for the sit bones and then hold the tape at each bone point. Flip upright without letting go of the tape and read your measurement. Voila!

I never had luck with the sitting on gel-like things as I have way to much butt padding to get a good reading.

I was surprised at how narrow my sit bones were. I always thought that being a big bottomed girl meant that I had wide hips. Not so much (which explains why my thighs will ALWAYS touch no matter how thin I get!). :p

zoom-zoom
06-30-2010, 05:21 PM
Ditto this.

Hold a fabric measuring tape in one hand. Lie on your back and flip your legs into the air (kind of over your head but you don't need to go that far). Feel for the sit bones and then hold the tape at each bone point. Flip upright without letting go of the tape and read your measurement. Voila!

I never had luck with the sitting on gel-like things as I have way to much butt padding to get a good reading.

I was surprised at how narrow my sit bones were. I always thought that being a big bottomed girl meant that I had wide hips. Not so much (which explains why my thighs will ALWAYS touch no matter how thin I get!). :p

Ditto...all of it. Even when I was a size 2 (by modern sizing) in HS I wore the inner thighs of my jeans out fast. At the time I was all of 115#s at 5'3"ish.

OakLeaf
06-30-2010, 07:20 PM
I think making an impression is better than using a tape measure, because the sitbones aren't parallel to the sagittal plane. An impression gives you not only the inside and outside measurements, but the angle.

And I think the inner thigh rub has to do with Q-angle and adductor development. It's an issue for me and my moderately wide bones, too.

Chicken Little
06-30-2010, 08:29 PM
I am thinking the water base paint thing might work. I'm trying it this weekend.

Zelda_K
07-02-2010, 10:42 PM
And so Zelda - do you notice any difference in comfort between your two different widths of Ariel seats? I also have the 143 (came on my Era) and absolutely love it but am unsure whether it is predominantly the width or shape that does it for me and how transferable that is to another Spesh seat.

I'm not as happy with the seats I have on my roadies and would like to try a Jett or similar but am reluctant to shell out the dollars if it is going to be a disaster.

I tried the yoga mat method, but it didn't work for me. maybe i should have been sitting there a bit longer, will try again.

as for my 2 Ariel saddles, I don't notice much difference. But then they are on my mountainbikes, where I spend more time standing on the pedals or just leaning my legs against the saddle, not really sitting on it like on the road bike. And I rarely spend more than 2 hours on my mountainbikes (unlike the road which I use for much longer trips).

lph
07-02-2010, 11:55 PM
(mine are 170-190mm, and my hips themselves are not very wide. Sit bone width and hip width don't have much to do with each other)

Just wanted to ditto this - there really is very little correlation. I have narrow hips but quite wide sitbones. Yesterday I saw a rare pic of me biking taken from behind and it was actually visible, both the wide "seating" and the thigh bone that seemingly goes straight down.

malkin
07-03-2010, 05:13 AM
Me too with the wide sit/narrow hip.
In fact, it feels like the distance between my sit bones is wider than the distance from either one of them to the outside world on the side.

ny biker
07-03-2010, 07:33 AM
[QUOTE=Zelda_K;518406]I tried the yoga mat method, but it didn't work for me. maybe i should have been sitting there a bit longer, will try again./QUOTE]

I was semi-successful using a mat. I folded it in fourths and put it on my dining room table, which has a marble top. The impressions don't last for long but I was able to get a outside to outside measurement that is similar to what I got when I just took a tape measure to my up-ended butt.

It looks like I'm measuring around 130-135 mm. My current saddle is 155 (or maybe 160?) and it's comfortable for me, so that makes sense.

BTW my current saddle is pretty close to perfect, but is wearing out (cover is cracking) so I need a new one. Sadly they don't make the one I have anymore, so I'm going to post pics of it in a separate thread in the hopes that someone can point me towards a new one with a similar shape.

OakLeaf
07-03-2010, 11:00 AM
Yoga mats tend to be thin and rather firm. I had good luck with a floorwork mat that's maybe 8 mm - 1 cm thick.

Remember to sit low enough (or elevate your feet enough) that your femurs and thigh flesh aren't keeping your sitbones from making a good impression.