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Bend ISM Saddle Rails to Make Centre Cutout Wider
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I've seen quite a few people talk about using zip ties to make the nose of an ISM saddle narrower, but I think I want to do the opposite (make the front wider) and wanted to get peoples thoughts before I go ahead and bend the rails of a saddle to do this. I'm curious to hear if others have done this, or felt the same way.

I have tried a number of different saddles on my tri bike over the years and have always struggled a bit with prenium pressure causing numbness (especially during winter long base rides on the trainer). ISM saddles (Attack and Prologue) have worked best for me due to the middle cutout, but I've always felt like I wanted the centre cutout to be a bit wider to reduce pressure. If I tilt down the nose to the point that it doesn't cause me any numbness, then I find the support a bit lacking and my triceps get sore from working too hard to hold my body back. I usually sit in about the middle of an ISM saddle - I have heard the guidance about sitting right on the end, but at that point the centre groove is so narrow that it causes way too much pressure for me to sit there for any amount of time. When I am in aero position, my pelvis is rotated fairly far forward and my back is fairly flat. In aero position, my sit bones don't really naturally tough the saddle, I have to really consciously arch my back if I want to make my sit bones contact with the saddle.

I had an older ISM Attack saddle where I recently bent the front section of the saddle rails outward to make the centre cutout wider. This seemed to be a fairly big improvement and I was able to keep the saddle about level and have support, while not experiencing numbness. I was also able to sit at the end of the saddle as is normally described as the 'correct' way to sit on these saddles. Yes there was a bit more pressure on the inside of my thighs due to the increased width, but it wasn't a deal breaker and I was willing to live with that to have the numbness go away. The only issue with this setup was that I have always found the padding on this saddle to be a bit too firm and would like to have something a bit softer.

I just bought an ISM PR 2 with the intention of also bending the rails to make it a bit wider and then have more padding, but had a last minute hesitiation about the thought of bending a brand new saddle and figured I should check with the Slowtwitch community first.

Appreciate peoples thoughts on this.
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [Brad79] [ In reply to ]
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I did it, for exactly the reason you mentioned, worked great.

Damon Rinard
Engineering Manager,
CSG Road Engineering Department
Cannondale & GT Bicycles
(ex-Cervelo, ex-Trek, ex-Velomax, ex-Kestrel)
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [damon_rinard] [ In reply to ]
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Good to know, thanks. I guess I'll go ahead and bend the new saddle too.

Surprised this isn't something I've seen mentioned before - everyone seems to want narrow tri saddles, that definitely won't work for me.

Brad
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [Brad79] [ In reply to ]
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Doesn't work for me either. Its thin line though, too much width and I have other issues (in addition to inner leg chafing). It seems like some ISM saddles had a bit more width near the end than others.
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [Brad79] [ In reply to ]
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I made the cut out wider by pulling the padding off of an ISM Attack and gluing on two layers of heat moldable foam, using a dremel and sand paper to shape it, and then covering it with 3M dinoc carbon wrap. Worked great.



wovebike.com | Wove on instagram
Last edited by: milesthedog: Feb 20, 17 17:42
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [milesthedog] [ In reply to ]
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Tell me more about this hacked Attack saddle. What moldable foam did you use? Do you have any up close pictures?

thanks
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [beston] [ In reply to ]
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Foam: Acor Microcel Puff EVA Foam (Color: Black, Thickness: 3/16", Sub-Quantity: 1 Sheet) SKU: PUFF-00390

TT saddle - ISM Attack sheel with Acor padding added (2 layers) and then 3M dinoc. If you need the front opening even wider, you can use less padding, or sand away the padding more after adding it. I can get those wrinkles out with my heat gun. See the road saddle below to see how smooth it can be done - I just spent more time on the road saddle to date. The opening is wider on this saddle than on the Attack with room to go wider:


Road Saddle: Took the rails off of a Dash Tri.7. Molded a carbon shell from an ISM Podium shell. Added one layer of Acor foam padding (a Simmons project):


The shell had a bit more contour do it that I liked, so I added some strips of padding to flatten on the rear and add flatter ledges along the curved down outside edges of the rear of the saddle and the covered with 3M dinoc (a bit dirty in this photo due to some muddy rides recently). The opening on this saddle could be a 2-3mm wider at the nose - there is no TT riding on this saddle, but it is amazing for road riding, though when I get super low, I wish the opening were wider at the front - it will be a future update. I ride with adam-hansen-eque drop and have no issues with this saddle.


wovebike.com | Wove on instagram
Last edited by: milesthedog: Feb 21, 17 6:56
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [milesthedog] [ In reply to ]
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Thanks for the saddle info. Nice bike, too. What's the story with it? What modifications have you done, if any?
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [Brad79] [ In reply to ]
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Brad79 wrote:
I've seen quite a few people talk about using zip ties to make the nose of an ISM saddle narrower, but I think I want to do the opposite (make the front wider) and wanted to get peoples thoughts before I go ahead and bend the rails of a saddle to do this. I'm curious to hear if others have done this, or felt the same way.

I have tried a number of different saddles on my tri bike over the years and have always struggled a bit with prenium pressure causing numbness (especially during winter long base rides on the trainer). ISM saddles (Attack and Prologue) have worked best for me due to the middle cutout, but I've always felt like I wanted the centre cutout to be a bit wider to reduce pressure. If I tilt down the nose to the point that it doesn't cause me any numbness, then I find the support a bit lacking and my triceps get sore from working too hard to hold my body back. I usually sit in about the middle of an ISM saddle - I have heard the guidance about sitting right on the end, but at that point the centre groove is so narrow that it causes way too much pressure for me to sit there for any amount of time. When I am in aero position, my pelvis is rotated fairly far forward and my back is fairly flat. In aero position, my sit bones don't really naturally tough the saddle, I have to really consciously arch my back if I want to make my sit bones contact with the saddle.

I had an older ISM Attack saddle where I recently bent the front section of the saddle rails outward to make the centre cutout wider. This seemed to be a fairly big improvement and I was able to keep the saddle about level and have support, while not experiencing numbness. I was also able to sit at the end of the saddle as is normally described as the 'correct' way to sit on these saddles. Yes there was a bit more pressure on the inside of my thighs due to the increased width, but it wasn't a deal breaker and I was willing to live with that to have the numbness go away. The only issue with this setup was that I have always found the padding on this saddle to be a bit too firm and would like to have something a bit softer.

I just bought an ISM PR 2 with the intention of also bending the rails to make it a bit wider and then have more padding, but had a last minute hesitiation about the thought of bending a brand new saddle and figured I should check with the Slowtwitch community first.

Appreciate peoples thoughts on this.


I was just looking for info on google to do this and came to this post!

I have the same exact problem and saddle. But its not numbness what iI have is actual pain in the jewels, although theres no pressure on them but on the perineal area I think.
I had the adamo road on the road bike and was ok so I bought the attack for the new tri bike (BMC TM02 2017). and can't bike for more than one hour, after that pain starts for a couple days (In the balls).
Right now I had the idea to wider the front rails so I left a tool between them making pressure, I will leave it for the night and check tomorrow.
Also thinking on buyer a seat with wider cutout, thinking on fizik tritone or dash stages.

So how was your experiment? any advise?

thanks
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [hisholiness] [ In reply to ]
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The ISM Attack saddle with widened rails was somewhat tolerable, but bending the rails on the PR2 did not work for me at all. I think this is because the softer PR2 saddle prongs widened under pressure, whereas the harder Attack prongs stayed roughly the same width.

The end result of my experimenting was to realize that I was probably sitting on the saddle the wrong way in the first place and this was in fact the cause of my problems. My guidance for how to sit on a tri saddle had been to try to rotate my pelvis forward to achieve a flat back and I think I had been riding with my pelvis rotated way too far foward.

With my pelvis rotated so far forward, the only place to support me without causing perineum pressure was a small space between the inside of my legs and perineum. This space was too thin to comfortably support me. I was able to achieve this type of support with the ISM Attack and bent rails, but it was still not comfortable, due to the high pressure of being supported by such a thin area.

I was also having hamstring issues crop up during races which I came to realize were also probably caused by my pelvis being rotated so far forward.

What brought this to a head is when I tried to lower my position this year. I had been bike fit several times in the past to try and address the hamstring issues and all the fitters responded by raising the front end of my bike very high. This year I decided I was tired of riding with such a high front end and decided to see if I could find a way to ride with a lowered front end, or else abandon rising a tri bike and switch to a road bike (I didn't have any hamstring issues in a road bike). As I lowered the front end, I found it impossible to tolerate any saddles and after my experiments in prong bending, realized I was doing something wrong, because there was no way I was ever going to find comfort with my pelvis rotated so far forward.

I then decided to make a conscious effort not to rotate my pelvis forward and instead bend my lower back and try to sit on my sit bones. This has been taking a while to get used to, since I rode for a number of years with my pelvis rotated very forward. So far I think the results are positive, I have the front end lower and it seems comfortable, I switched to the Cobb JOF 55 and it's (almost) comfortable, and I haven't had the former hamstring issues pop up yet. The real test for me will be when I get into race season this summer, because my former hamstring issues only cropped up during races.

I'm quite hopeful that this will eliminate my hamstring issues and allow me to ride with a low front end like the cool kids do...

As a side note, before I couldn't imagine being comfortable on a saddle like the JOF due to its narrowness and relatively thin cutout, but it seems to be working and I love having a thinner nose that doesn't always run against my thighs.

Brad
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [Brad79] [ In reply to ]
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My PN 2.1 nose has bent slightly on its own. One prong was slightly higher than the other by 2 or 3mm. I have bent it back and I'm hoping it stays in the level position now, maybe I had impacted one of the prongs previously.

The rails are chromoly (alloy steel) so I'm guessing some plastic deformation should be okay.
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Re: Bend ISM Saddle Rails to Make Centre Cutout Wider [milesthedog] [ In reply to ]
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another ST gold nugget of a thread for those in need of something a little off the beaten path, but sport wise quite specific :-)

Anyone tried this wth a specialized sitero?

I have a broken latest model sitero and a new need for a seat for a UCI legal TT project.

I think I'll have a go with a diy modification as the original is just too narrow for off the front use. The seat failed at the metal holding the front saddle rails so this might not be too difficult to test or make permanent.

thanks, jason

__________________________________________
nz
rst, then slowtwitch lurker since '93
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