Go Back  Bike Forums > Bike Forums > Road Cycling
Reload this Page >

How many millimetres to add to sit bones for saddle fit of road bike?

Notices
Road Cycling “It is by riding a bicycle that you learn the contours of a country best, since you have to sweat up the hills and coast down them. Thus you remember them as they actually are, while in a motor car only a high hill impresses you, and you have no such accurate remembrance of country you have driven through as you gain by riding a bicycle.” -- Ernest Hemingway

How many millimetres to add to sit bones for saddle fit of road bike?

Old 06-18-16, 03:04 PM
  #1  
Senior Member
Thread Starter
 
Join Date: Jul 2015
Posts: 393
Likes: 0
Liked 0 Times in 0 Posts
How many millimetres to add to sit bones for saddle fit of road bike?

I found out I have wide sit bones today which I figured since 150mm and under were all torture devices.

I went to specialized and he measured me at 148mm sit bones. He then told me a 155mm was perfect so I went with the 155 Romin Evo Expert Gel earlier today.

I asked him shouldn't I be in the 168mm with those sit bones and he said definitely not. I thought I read online that you're supposed to go up 20mm but I didn't want to over rule his decision since he was so confident about it.

The 155mm supports them but if I tilt a lot to one side I can feel them roll off. Is that okay?

Anyway it's a nice saddle so far. I'm on the road right now. Also specialized has guarantee so I can go in and switch if I don't like it.
exime is offline  
Old 06-18-16, 04:51 PM
  #2  
Senior Member
 
Kevindale's Avatar
 
Join Date: Apr 2013
Location: Amsterdam
Posts: 1,662

Bikes: 1980 Koga-Miyata Gentsluxe-S, 1998 Eddy Merckx Corsa 01, 1983 Tommasini Racing, 2012 Gulf Western CAAD10, 1980 Univega Gran Premio

Likes: 0
Liked 11 Times in 11 Posts
I've been going through these issues lately. The bottom line is that the measurement of the sit bones bit is really only vaguely useful. I recently tried the Romin Evo, and liked it, though I got a deal on a Sella SMP Dynamic that I'm going with (second ride in a few minutes). My sit bones are narrow, and by the 'add 20 mm' rule I should be good with something even a bit narrower than the 143 mm Romin saddle, but the 155 was strongly recommended by the guy at the LBS. He's also slight (shorter than me but at least as thin), and he said he could never get used to the 143 mm Romin, but loves the 155 and can sit on it all day.

It's become clear to me that the flatness vs. roundness of the saddle, and the degree of central cutout, are really crucial. Also, the so-called sit bone doesn't have a single width -- towards the rear these ridges are wider, and go narrow towards the front. And we all have varying degrees of how rounded or flat these ridges are, so there's really no single measurement that is truly meaningful.

Try the 155 for a few more days. If you still have doubts, go try the 168 mm. Also be willing to play around a bit with seat setback and tilt in a careful, methodical way.
Kevindale is offline  
Old 06-18-16, 05:23 PM
  #3  
Senior Member
 
Join Date: Dec 2011
Posts: 305
Liked 41 Times in 20 Posts
At the end of the day your ass has the last word, despite whatever the experts say. Go for a few long rides and if you still are uncomfortable, take advantage of generous exchange policy to exchange to something that will work better for you.
yamsyamsyams is offline  
Old 06-18-16, 06:32 PM
  #4  
Senior Member
 
lwrncc's Avatar
 
Join Date: Oct 2010
Posts: 237
Likes: 0
Liked 0 Times in 0 Posts
I think according to Specialized's on guide, you should be on 168mm saddles unless you have a very aggressive potion.

This detailed post below is by WR304 from mtbr forums:

You can measure your sit bones to get an idea of what saddle width might be suitable. This is something you can do at home. All you need is to make an imprint of your sit bones. This video shows one way of doing it:


https://m.youtube.com/watch?v=E7j9LUVJrjA


Once you have that measurement here are the instructions regarding saddle width:





The Power saddle isn't listed on the table of widths below. I think you can assume it would come under the Black heading though (Romin, Romin Evo, Phenom).








With saddle widths a saddle that's too narrow often isn't great. If your sitbones aren't supported then it can be a real "ass hatchet". You're sitting directly on the soft tissue between the sit bones, rather than supporting your body weight through your pelvis as intended.


You can go too wide with saddles as well though. On the Specialized ass-o-meter I measure somewhere between a 143mm and a 155mm saddle. I rode a 155mm width Specialized saddle back in 2008. What I found with that wider saddle was that the back of my thighs, around where the hamstrings insert, would hit the saddle whilst pedalling. I couldn't really sit back on the saddle in the normal location as intended. I wound up sitting perched further forwards towards the nose instead, where the saddle wasn't as wide.


Since then I've stuck with the 143mm width Specialized saddles as that seems about right for me.


Something to bear in mind is that as you try harder a slightly narrower saddle can start to feel better. To get a feel for a saddle you need to do some hard efforts. As you try harder you tend to change position on the bike and crouch down, changing how you sit on the saddle. A saddle width and shape that can seem just right pootling along at a relaxed pace might feel a bit wide when you're chewing the handlebars at maximum effort.





In the UK Specialized offer a 30 day trial period where you can try a saddle, and then if you don't like it swap it for a different model of Specialized saddle. I'm not sure if that applies in other countries too but it might.


Specialized Saddles Satisfaction Guaranteed
lwrncc is offline  
Old 06-18-16, 06:52 PM
  #5  
Senior Member
 
Northwestrider's Avatar
 
Join Date: Apr 2006
Location: Gig Harbor, WA
Posts: 2,470

Bikes: Surly Long Haul Trucker, Gary Fisher Hoo Koo E Koo, Dahon Mu P 24 , Ritchey Breakaway Cross, Rodriguez Tandem, Wheeler MTB

Likes: 0
Liked 0 Times in 0 Posts
One manufacturer seems to think sit bone measurements are not all that useful , ISM saddles are intended to be used by sitting on the narrow forward part of their saddle. I've ordered one, the majority of it's reviews I've seen are positive. I'll know for sure after a few days .
Northwestrider is offline  
Old 06-19-16, 12:10 AM
  #6  
Senior Member
 
rbk_3's Avatar
 
Join Date: May 2015
Location: Ontario, Canada
Posts: 233

Bikes: Trek Emonda S6

Liked 0 Times in 0 Posts
I went through this last year and it was a nightmare. I have very wide sitbones and took me like 10 saddles before I found the Specialized Power. That thing is phenomenal. The guy doesn;t know what he is talking about. You most certainly want the 168mm.

This thread may be helpful to you

https://www.bikeforums.net/road-cycli...8mm-romin.html

Last edited by rbk_3; 06-19-16 at 12:14 AM.
rbk_3 is offline  
Old 06-19-16, 01:40 AM
  #7  
Senior Member
Thread Starter
 
Join Date: Jul 2015
Posts: 393
Likes: 0
Liked 0 Times in 0 Posts
Really good information from everyone.thanks. Sounds like I'm not the only one going through this. So far the only saddle that hasn't caused butt pain for me is my Planet Bike ARS Standard 7" gel saddle that I use on my hybrid (and now on road until I find a good seat). It's a little too big though because it causes inner thigh chafing and impedance on my pedal stroke on the back of my thighs. However, I can still come back from a 60 mile trek with a fresh butt which is huge.

I did 63 miles today (Around 55 miles on the new 155 Evo Expert Romin) and I definitely can't really say the same although my pedal stroke is a lot freer in back of thigh and no friction on inner thigh. It seemed to be doing pretty good (a lot better than the other saddles I've tried inc. bontrager/selle italia) until about mile 40-45 and then I started getting the same pain as the other road saddles I tried. It wasn't so bad that I had to pedal standing up for the last couple miles home (like I did with my 138 stock saddle by mile 30) but it was enough that I wouldn't have been able to do a Century and I'd have to had call it quits. My sit bones are still tender right now. My weekend rides are normally 60ish miles and I want to be able to do a century so a "good until mile 40 saddle" isn't going to work. But I'm holding the standard to my Planet Bike hybrid seat. Surely if my butt feels good on that after 60 miles, then I can find a decent road bike seat that doesn't hurt.

Thankfully tomorrow (today) is Sunday so I can get another big day in to test it.

so far:

bontrager paradigm 138mm - uncomfortable and extremely painful by mile 20

fizik antares 142mm - uncomfortable extremely painful by mile 20

Bontrager serano 148mm - no cut out, perineum pain.

Selle Italia Turbomatic 153mm - decent then painful by mile 30

specialized romin evo gel 155mm - pretty comfortable then painful by mile 40

Last edited by exime; 06-19-16 at 01:50 AM.
exime is offline  
Old 06-19-16, 02:08 AM
  #8  
Senior Member
 
rbk_3's Avatar
 
Join Date: May 2015
Location: Ontario, Canada
Posts: 233

Bikes: Trek Emonda S6

Liked 0 Times in 0 Posts
Originally Posted by exime
Really good information from everyone.thanks. Sounds like I'm not the only one going through this. So far the only saddle that hasn't caused butt pain for me is my Planet Bike ARS Standard 7" gel saddle that I use on my hybrid (and now on road until I find a good seat). It's a little too big though because it causes inner thigh chafing and impedance on my pedal stroke on the back of my thighs. However, I can still come back from a 60 mile trek with a fresh butt which is huge.

I did 63 miles today (Around 55 miles on the new 155 Evo Expert Romin) and I definitely can't really say the same although my pedal stroke is a lot freer in back of thigh and no friction on inner thigh. It seemed to be doing pretty good (a lot better than the other saddles I've tried inc. bontrager/selle italia) until about mile 40-45 and then I started getting the same pain as the other road saddles I tried. It wasn't so bad that I had to pedal standing up for the last couple miles home (like I did with my 138 stock saddle by mile 30) but it was enough that I wouldn't have been able to do a Century and I'd have to had call it quits. My sit bones are still tender right now. My weekend rides are normally 60ish miles and I want to be able to do a century so a "good until mile 40 saddle" isn't going to work. But I'm holding the standard to my Planet Bike hybrid seat. Surely if my butt feels good on that after 60 miles, then I can find a decent road bike seat that doesn't hurt.

Thankfully tomorrow (today) is Sunday so I can get another big day in to test it.

so far:

bontrager paradigm 138mm - uncomfortable and extremely painful by mile 20

fizik antares 142mm - uncomfortable extremely painful by mile 20

Bontrager serano 148mm - no cut out, perineum pain.

Selle Italia Turbomatic 153mm - decent then painful by mile 30

specialized romin evo gel 155mm - pretty comfortable then painful by mile 40

I am telling you, try the Specialized Power 168mm. Not only is it 168mm but it doesn't arc off so it is heaven for wide sit bones. It was the single greatest cycling purchase I have ever made. Your situation is exactly like mine with almost the same width of sitbones.

https://www.specialized.com/ca/en/co...-expert/105546

I tried 2 of those you tried initially, the Bontrager Paradigm and the Specialized Roman. Like you I initially thought the Roman was going to work but the next day I had the extreme pain in the taint area. I found while the Romin was 155mm, the flat area where my sitbones sat were not anywhere close to 155mm

Last edited by rbk_3; 06-19-16 at 02:14 AM.
rbk_3 is offline  
Old 06-19-16, 02:36 AM
  #9  
Senior Member
 
Join Date: Aug 2012
Posts: 459
Liked 2 Times in 2 Posts
+1 on Power saddle, it's so good I barely notice them
bleui is offline  
Old 06-19-16, 04:26 AM
  #10  
Senior Member
 
Join Date: Dec 2012
Location: Okefenokee Swamps.
Posts: 577

Bikes: Rockhopper, Azor Oma cruiser

Likes: 0
Liked 2 Times in 2 Posts
On my mtn bike using upright handlebars I've installed the Brooks B17N Imperiale saddle and that's been the answer to all of the other high quality seats that ill-fit me. On my dutch cruiser I've installed the Brooks B67 saddle that took about 200 miles to break in and it feels great. I'm 72" tall and weigh 230 #, approx 11+ stones.

Last edited by tjkoko; 06-19-16 at 09:49 AM.
tjkoko is offline  
Old 06-19-16, 09:47 AM
  #11  
Senior Member
Thread Starter
 
Join Date: Jul 2015
Posts: 393
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by rbk_3
I am telling you, try the Specialized Power 168mm. Not only is it 168mm but it doesn't arc off so it is heaven for wide sit bones. It was the single greatest cycling purchase I have ever made. Your situation is exactly like mine with almost the same width of sitbones.

https://www.specialized.com/ca/en/co...-expert/105546

I tried 2 of those you tried initially, the Bontrager Paradigm and the Specialized Roman. Like you I initially thought the Roman was going to work but the next day I had the extreme pain in the taint area. I found while the Romin was 155mm, the flat area where my sitbones sat were not anywhere close to 155mm
I actually had the Power next to the Romin at the shop and I couldn't decide but I went with the Romin on a whim. It's shaped almost identical to the selle italia that I tried and didn't work so in hindsight I should have just tried the Power from the start. I'll have to try the Power next thanks. You're right about the measurement too. It doesn't feel like a 155mm saddle..
exime is offline  
Old 06-19-16, 11:13 AM
  #12  
Fresh Garbage
 
hairnet's Avatar
 
Join Date: Apr 2009
Location: Los Angeles
Posts: 13,190

Bikes: N+1

Liked 27 Times in 18 Posts
Originally Posted by tjkoko
On my mtn bike using upright handlebars I've installed the Brooks B17N Imperiale saddle and that's been the answer to all of the other high quality seats that ill-fit me. On my dutch cruiser I've installed the Brooks B67 saddle that took about 200 miles to break in and it feels great. I'm 72" tall and weigh 230 #, approx 11+ stones.
Not really helpful when we're discussing road bikes. I have a Brooks B17 that I love, but it's on my touring bike as intended. These saddle's shapes don't work so well if you have the handlebar set very much lower than the saddle.
hairnet is offline  
Old 06-19-16, 11:34 AM
  #13  
Banned
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Posts: 43,598

Bikes: 8

Liked 1,361 Times in 867 Posts
Planning a surgical Implant to your Pelvis?
fietsbob is offline  
Old 06-19-16, 03:03 PM
  #14  
Senior Member
Thread Starter
 
Join Date: Jul 2015
Posts: 393
Likes: 0
Liked 0 Times in 0 Posts
So you guys were right. It was too small.

A lot of pain still this morning. So I went back and talked to another guy. He measured me at 148mm again. He said I should definitely be in a 168mm! Music to my ears. I knew the 155mm was way too small for me. So I bumped up to a 168mm power and it already feels so much better albeit I still have the pain from yesterday and I haven't done the 60 mile test yet. I can't roll my sit bones off the sides anymore either so I know I'm getting proper support.

Hopefully it works on my next big ride.
exime is offline  
Old 06-19-16, 11:03 PM
  #15  
Senior Member
 
rbk_3's Avatar
 
Join Date: May 2015
Location: Ontario, Canada
Posts: 233

Bikes: Trek Emonda S6

Liked 0 Times in 0 Posts
Originally Posted by exime
So you guys were right. It was too small.

A lot of pain still this morning. So I went back and talked to another guy. He measured me at 148mm again. He said I should definitely be in a 168mm! Music to my ears. I knew the 155mm was way too small for me. So I bumped up to a 168mm power and it already feels so much better albeit I still have the pain from yesterday and I haven't done the 60 mile test yet. I can't roll my sit bones off the sides anymore either so I know I'm getting proper support.

Hopefully it works on my next big ride.
Glad to hear. Keep us updated. Curious to see if the Power saved another cyclist !
rbk_3 is offline  
Old 06-20-16, 04:08 AM
  #16  
Voice of the Industry
 
Campag4life's Avatar
 
Join Date: May 2007
Posts: 12,572
Likes: 0
Liked 8 Times in 8 Posts
Exime,
Do you sit bolt upright on your bike? Sit bone width depends on pelvis rotation or lack there of.
Never heard of anybody measuring 148mm width across their sit bones.
To me the ass-o-meter is highly flawed because it doesn't replicate riding position unless it happens to agree with how a rider sits on his bike unless the test assistance knows to coach the person being measured.

A cruiser needs a wider saddle than a road bike because of how the same rider sits on the seat.
Campag4life is offline  
Old 06-20-16, 05:10 AM
  #17  
Ride On!
 
deapee's Avatar
 
Join Date: Apr 2016
Posts: 971

Bikes: Allez DSW SL Sprint | Fuji Cross

Likes: 0
Liked 3 Times in 3 Posts
Mine were wide when I had them measured too. I think around 130'ish mm.

IF you were sitting straight up, your measurement is off. Those bones go inward as you lean forward.

That being said, I am comfortable on a (road bike) 143 toupe or 155 romin.
I think for mountain bike I'm going to use a Targa in 155.

The pain from a too-narrow saddle is one you will know within about 5-6 miles. It's an unrelenting pressure right in the middle down there. For me, if it's too narrow AND too much padding, it's even worse. If you recognize it and cut your ride short, it's no biggie and you can get back on and test the next day or even right then, but if you go too long on it, you absolutely need to take a couple of days off because it starts to feel like you're sitting on a metal pipe.

--

But yes, TLDR: I think that if you were positioned properly when they were measured, you need a 168 in a Romin or a 155 in a Toupe.
Technically speaking, and this is a pretty important piece -- there's no such thing as too wide a seat if your inner thighs aren't banging the seat on every down stroke.
deapee is offline  
Old 06-20-16, 08:16 AM
  #18  
Senior Member
Thread Starter
 
Join Date: Jul 2015
Posts: 393
Likes: 0
Liked 0 Times in 0 Posts
Originally Posted by Campag4life
Exime,
Do you sit bolt upright on your bike? Sit bone width depends on pelvis rotation or lack there of.
Never heard of anybody measuring 148mm width across their sit bones.
To me the ass-o-meter is highly flawed because it doesn't replicate riding position unless it happens to agree with how a rider sits on his bike unless the test assistance knows to coach the person being measured.

A cruiser needs a wider saddle than a road bike because of how the same rider sits on the seat.
I have a very small drop on my Trek SL5. So not upright but not super aggressive. 148 isn't normal? The only thing he had me do was lift up my heels. Maybe it was off a little bit but I'm still pretty confident that I have pretty wide sit bones since anything 155mm and under gives me severe pain. My 7" Planet Bike gel seat is a dream for my sit bones but it's not good at all for road biking. It stays on my hybrid. I won't know if this 168mm works yet because my sit bones are still healing from my last painful ride, but on the small mileage I put on it it feels a lot better than the 155.
exime is offline  
Old 06-20-16, 09:18 AM
  #19  
Senior Member
 
Fox Farm's Avatar
 
Join Date: Aug 2004
Location: Prague, Czech Republic
Posts: 2,755

Bikes: Merlin Extra Light, Orbea Orca, Ritchey Outback,Tomac Revolver Mountain Bike, Cannondale Crit 3.0 now used for time trials.

Liked 55 Times in 34 Posts
A few years ago, Colorado Cyclist would like the width of the saddles that they sold. I tend to have normal to wider site bones. I am a man. The Sella Italia Flite Max works just fine for me. I tried some of the Fizik long saddles and they were much too narrow, placing most of the weight on my nither and not the sit bones. I have noted that Terry also makes wider saddles, not just for women.
Fox Farm is offline  
Old 06-20-16, 10:37 AM
  #20  
Senior Member
 
bmthom.gis's Avatar
 
Join Date: Aug 2014
Location: Columbia, SC
Posts: 2,977

Bikes: 2014 Cannondale Synapse Carbon 4 Rival; 2014 Cannondale Trail 7 29; 1972 Schwinn Suburban, 1996 Proflex 756, 1987(?) Peugeot, Dahon Speed P8; 1979 Raleigh Competition GS; 1995 Stumpjumper M2 FS, 1978 Raleigh Sports, Schwinn Prologue

Likes: 0
Liked 4 Times in 4 Posts
Originally Posted by hairnet
Not really helpful when we're discussing road bikes. I have a Brooks B17 that I love, but it's on my touring bike as intended. These saddle's shapes don't work so well if you have the handlebar set very much lower than the saddle.
Originally Posted by tjkoko
On my mtn bike using upright handlebars I've installed the Brooks B17N Imperiale saddle and that's been the answer to all of the other high quality seats that ill-fit me. On my dutch cruiser I've installed the Brooks B67 saddle that took about 200 miles to break in and it feels great. I'm 72" tall and weigh 230 #, approx 11+ stones.
I've got a B17N on my road bike and a C17 on my commuter. No reason to restrict these saddles to upright riding duty. I find them both to be very comfortable with the saddle-higher-than-the-handlebars, even when in the drops. If the seat-to-handlebar drop is really big, try out a Swift! Personally I don't see the need to ever buy a different brand. But it's my ass.
bmthom.gis is offline  
Old 06-20-16, 11:13 AM
  #21  
Fresh Garbage
 
hairnet's Avatar
 
Join Date: Apr 2009
Location: Los Angeles
Posts: 13,190

Bikes: N+1

Liked 27 Times in 18 Posts
Originally Posted by bmthom.gis
I've got a B17N on my road bike and a C17 on my commuter. No reason to restrict these saddles to upright riding duty. I find them both to be very comfortable with the saddle-higher-than-the-handlebars, even when in the drops. If the seat-to-handlebar drop is really big, try out a Swift! Personally I don't see the need to ever buy a different brand. But it's my ass.
Sure, but I quoted him talking about his dutch cruiser. I've tried my B17 on a few bikes and it stopped feeling good on my bikes with the bar several inches lower than the saddle because the sides started to rub my thighs. You see on the Brooks for road bikes they trim the sides off.
hairnet is offline  
Old 06-20-16, 01:32 PM
  #22  
Senior Member
 
Join Date: Nov 2009
Posts: 407
Liked 0 Times in 0 Posts
+1 for the Specialized Power saddle, especially for the shorter nose. However, I'm starting to have issues with the sides pinching the insides of my thighs while I ride and I find myself perched out near the tip sometime. Can't figure it out, but I'm thinking it has to do with the "flatness" of the "wings" for lack of better terms. I feel like if the sides rounded down more just after the area that supports your sitbones, it would be much more comfortable. Hopefully this makes sense.
cave12man is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bakeoh99
Road Cycling
5
11-26-13 05:17 PM
jim p
Fifty Plus (50+)
23
05-07-12 05:48 PM
milesmilesmiles
Road Cycling
3
06-30-10 08:03 AM
wstandis
Clydesdales/Athenas (200+ lb / 91+ kg)
23
04-29-10 09:01 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Your Privacy Choices -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.