question about width of SI diva gel flow

[Trek420]

I'd bet it's on the verge of being too narrow, but the bigger problem might be that it is too pear-shaped for you. The motion of your hip joints might require a saddle that is more T-shaped.

Center-to-center on my SI Ldy is about 4 inches, and the over-all width is about 6 inches. My center-to-center on my sit bones is about 3 1/2 inches. I have Selle Italia saddles on two of my bikes, I looove the Selle Italia saddles more than any other.

[Grits]

I think you are right, Trek. Too narrow AND too pear shaped. It is hard to find something wider and T-shaped! Suggestions welcome!

[KnottedYet]

I think you are right, Trek. Too narrow AND too pear shaped. It is hard to find something wider and T-shaped! Suggestions welcome!

Brooks B68/B67 is pretty much the ultimate wide (210mm) and T-shaped saddle. Very sexy, very classic. I have 3.

[Veronica]

Brooks B68/B67 is pretty much the ultimate wide (210mm) and T-shaped saddle. Very sexy, very classic. I have 3.

But if Grits' sit bones measure 152 mm won't she have issues with too wide of a saddle?

Veronica

[KnottedYet]

But if Grits' sit bones measure 152 mm won't she have issues with too wide of a saddle?

Veronica

As I said, it's the ultimate wide and T-shaped saddle, she said she didn't know of one wider and more t-shaped than what she had. Knowledge is power. At least she knows it exists now. The B67/B68 is the Jolly Green Giant of wide and T-shape. There are many others. She asked for suggestions. C'mon, kids, chip in with some more saddle names!

You do not insert a saddle. You perch ON it. Perching on something too wide should not be a problem. I can perch my sit bones on the center of a bench and the added width doesn't irritate me. Damm bench is a good 3 feet too wide on either side.

People forget the hip joint is FORWARD of the ischial tuberosities. If there is more saddle to the sides of the tuberosities it doesn't matter. It's wasted space, but it doesn't interfere with anything.

However, if there is too much saddle in front of the tuberosites (where the transition is, the ol' pear vs. T) where the hip joint needs room to move, yeah, BIG problem!

Looking at Trek420's Selle Italia saddle, that sucker is mighty pear-shaped compared to my B68 right next to it. The angles of her pubic rami and hip joints are happy with that pear, which would kill me (if they made it wide enough for me in the first place). I get chafing exactly as Grits describes when I ride a Serfas Niva. It is one of the very few saddles out there that is wide enough for me, but it is too pear shaped. My Brooks is T shaped (and a bit wider), and all is good.

In Grits' case, it's more likely the saddle is too pear shaped than that it is too narrow.

Chafing where the butt meets the leg is the hip motion dragging the skin along the saddle forward of the sit bones.

The ischial tuberosities don't move, that's why we sit on them.

Hip joints do move, that's why saddles get narrow, to get out of the way. If the saddle doesn't get narrow fast enough, it gets in the way and the moving femur drags tissue against the saddle transition zone.

LBS and saddle companies are starting to get the idea about sit bone width. I have faith that soon pear/T will spring to the forefront of the minds of shop clerks when a woman walks in with a chafing problem.

Bits chafe when they need to move and something gets in their way. Bits hurt and go numb when they are getting squished.

If I ever design saddles, I think I'll name my company "Bits"....

[Veronica]

However, if there is too much saddle in front of the tuberosites (where the transition is, the ol' pear vs. T) where the hip joint needs room to move, yeah, BIG problem!

I'm afraid I still don't get it. Just perching no problem, (I'd like to see you pedal on that bench. ) but when you start to move won't that too wide saddle still get in the way? Your saddle is like two inches bigger than mine. That extra inch on either side has got to get in the way.

Veronica

[KnottedYet]

I'm afraid I still don't get it. Just perching no problem, (I'd like to see you pedal on that bench. ) but when you start to move won't that too wide saddle still get in the way? Your saddle is like two inches bigger than mine. That extra inch on either side has got to get in the way.

Veronica

I could pedal on that bench, and I bet the cars would give me my passing space!

What is that inch going to get in the way OF? Nothing moves from the contact point of the ischial tuberosities on back, and nothing is moving on the sides (the hip is flexing and extending, not abducting and adducting)

I have two pelvis models (one male, one female) that I use when I am doing bike fit education presentations. I also have an articulated skeleton. They are great for showing people where the bones are, where things move, and where the saddle should be. If you can get a hold of a skeleton (or just a pelvis) put it on your saddle and look at how it works mechanically. It's very cool!

I just perched my sit bones on the edge of my kitchen chair. I could move my hips through the full range of hip flexion and extension that I'd need on the bike. The 16 1/2 inches of chair did not get in the way because it was behind my hip joints. That's 8 1/2 inches wider than my saddle. It could be 8 1/2 feet wider than my saddle, and it still wouldn't bother my hip motion.

http://en.wikipedia.org/wiki/Human_skeleton Sit bones and hip joints are in two different places. Support the sit bones without the supporting matterial getting in front of the sits and so getting in the way of hip motion, and the world is your oyster!

ETA: here's an even better self-exploration- sit on your spread hands. "March" your legs up and down. Feel how the limb motion is all in front of your sit bones? That's why saddles work, they are supporting the non-moving portion of your heinie. They can be 6 feet wide aft of the sit bone contact and still not interfere with the hip going through the pedalling motion.