Hands On: Bontrager's All New Serano Saddle Platform

These days, there is a lot that goes into the making of a new saddle platform. Rather than just simply designing a shape based on previous successes, saddle designers rely on medical science, elite rider testing, pressure mapping, high speed video, and even the use of FEA to see how human tissue will compress when seated on a saddle. Many saddle manufacturers have begun to incorporate pelvic width into selecting the proper sized saddle, but just as important is the selection of the right saddle for the rider’s posture. Bontrager breaks saddle usage down into five categories including Leisure, Fitness, Performance, Aggressive, and Aerodynamic. As you travel up the scale, saddles offer more curvature and more gradual transitions based on the seating position and rider posture.

As the latest saddle platform in their “Aggressive” category, the all new Serano offers a classic shape, in a saddle that is anything but. UPDATED with weights of all three Serano RLs plus more information on saddle sizing.

Tour de France - Stage 18

As the saddle underneath Andy Schleck since the Tour of California, Andy continued to use the Serano RXL throughout the Tour de France while a number of his team mates were riding the Team Issue. Like the other saddles in the Bontrager range, the Serano RL and Serano RXL will be offered in three inForm BioDynamics sizes. Using the inForm saddle sizer, consumers can be fit to the particular size at their local Trek dealer.

Hands On: Bontrager's All New Serano Saddle Platform

Hands On: Bontrager's All New Serano Saddle Platform Hands On: Bontrager's All New Serano Saddle Platform

Bontrager components RXL Serano Hilo bar277

Other than the futuristic looking Zone Density padding, the Serano’s shape is that of a classic saddle with curvy lines and a slight scoop at the tail. In marketing speak Bontrager refers to that as the “power pocket” or Posture 2, but it allows for the rider to settle back into the saddle, rotate the hips forward, and push off the back of the saddle for more power. The horizontal curvature has little flat space accommodating a more aggressive, forward leaning position, and a narrow nose to keep the thighs from rubbing on the saddle. Seranos are 270mm long and either 128, 138, or 148mm wide.

Bontrager components RXL Serano Hilo bar2793

Both the RL and RXL gain their lightweight support through a carbon reinforced shell – the difference between the two being the hollow Ti rails of the RL and oversized carbon fiber rails of the RXL.

Hands On: Bontrager's All New Serano Saddle Platform

That of course means you need an oversized rail compatible seatpost if you’re going to run the RXL. Some posts are compatible with both round and oval rails, but if you’re running a Bontrager seatpost like the XXX model here, you will need the 7x10mm saddle clamp (part #421564). The adapter is simple to install, and then allows for the saddle to be clamped with a single bolt – just make sure to use a torque wrench for the sake of the carbon!

Hands On: Bontrager's All New Serano Saddle Platform Hands On: Bontrager's All New Serano Saddle Platform

As Tyler has trained me to be one with my gram scale, the oversized rail adapters will add 7 grams to the post – which takes a small bite out of the RXL’s claimed 30g weight savings over the RL.

Bontrager components RXL Serano Hilo bar276

Bontrager Serano RL RXL Inform Saddle643

Bontrager Serano RL RXL Inform Saddle644 Bontrager Serano RL RXL Inform Saddle645 Bontrager Serano RL RXL Inform Saddle646

Though, our test Serano RXL in 138mm did come in 4g lighter than claimed, so there’s that. The black saddle was an early sample, while the white saddle that just showed up is 6g less. The Serano RLs on the bottom row range from 225g, to 237g – interestingly, it’s the middle sized, 138mm saddle that is the lightest. Claimed weights for the Serano RL are 210, 215, and 220g (128, 138, and 148mm) and 180, 185, and 190g for the RXL.

As it turns out, even with the 7g penalty for the oversized seatpost adapter, there is still around 43g difference between the RL and RXL.

Bontrager Serano RL RXL Inform Saddle635

Bontrager Serano RL RXL Inform Saddle636

White and black microfiber covers are available in both the RL and RXL models, though the RXL gets a few upgraded details like the embroidered tag on the rear instead of the embossed version on the RL. Pricing is set at $149.99 for the RL, and the more expensive RXL going for $224.99.

Bontrager Serano RL RXL Inform Saddle637

Bontrager Serano RL RXL Inform Saddle638 Bontrager Serano RL RXL Inform Saddle641

Sizing of the saddles is done at your local Trek dealer with the Bontrager inForm saddle sizer. The sizer uses a “Z-flo” compound (white goo) that is trapped in a clear, flexible vessel. Underneath is the position slider that is designed with one side for men and the other side for women. On each side you’ll find colors that match up with the saddle sizes.

Bontrager Serano RL RXL Inform Saddle639

Bontrager Serano RL RXL Inform Saddle640

Placing the sizer about 14 inches off the ground on a hard level surface (most shops will have a special bench for this), you’ll sit on the sizer with your back straight, allowing your sit bones to press into the Z-Flo. After marking the center of each impression with your finger, the slider is moved until the center of the impressions lines up with one color – in my case, yellow for 138mm.

First Impressions:

As a fan of the classic shaped saddles, my perineum has had little trouble adjusting to the Serano RXL. Sitting upright on the saddle with your hands off the bar to eat feels a little uncomfortable, but as soon as you tuck back into the bars that feeling goes away. It seems the more aggressive your positioning on the Serano, the more comfortable it becomes. I could see potential issues with cutout devotees, though it’s still worth a try if you still haven’t found the right saddle – especially considering Bontrager’s 30 day comfort guarantee. Based on the aggressive curvature of the saddle, the Serano seems like one that is very important to be sized correctly. So far, the Serano seems to be a hit.


  1. A very nice looking saddle – glad to not see any swoops or crazy graphics up top. They have a little bit of a Busyman Bicycles aesthetic going on with the perforated and raised midsection.

  2. looks promising and neat. i won’t need a saddle for a while, but i’ll consider these when that time comes. BUT Trek, please make those “ears” (both normal AND 7×10) available in black, too!

  3. so far I’ve tried this saddle in the 128mm width on a CX bike and MTB, both with quite a bit of drop to the handlebars. good results here….it’s like an old friend. I think anyone who’s ever enjoyed a flite classic saddle would find the Serano to be pretty comfy and maybe a little easier on the goochial area.

  4. No thanks. I’ve had other Bontrager saddles before. They don’t hold up to daily use. Stitching has been poor. Do a search yourself and see. I’m not the only one. And at the price they are asking?! Double no thanks.

  5. my coworker ordered his oversized rail saddle (paradigm in this instance) with his project 1 bike. but the rail clamps came black!! I’m stuck with aftermarket silver. ugh

  6. I think the quality of Bontrager saddles is great. I have had 3 and the one currently on my road bike I have used for almost 4 years now and haven’t seen any problems with the stitching. I look forward to trying one of these out they look comfy.

  7. @Ajax you must have a haggard butt or something because I haven’t seen a single Bontrager saddle exhibit any of the symptoms you describe. I have worked at a Trek dealer for about 4 years and sold countless Bontrager saddles.

  8. Never seen a Bonty saddle fail either….but to be honest I see almost none in any of the NE races I’m in. This new one looks like it might get better adoption rates and since Project One bikes are ramping up huge — I’ll be seeing more saddles from Bontrager. Maybe they will fail! But maybe not.

  9. I agree with the rest on no saddle issues. I’ve owned a couple of the older Inform RL’s and they were both great saddles and fit me well. I’m going to get one of these after the first of the year…

  10. Tried it at TrekWorld (Serano RL 128)

    My butt generally has not liked Bontrager saddles in the past…

    This saddle did not make itself known for a 20 mile high intensity ride. Seemed similar or better than my Fiziks.

    Definitely recommend trying it.

    (saddles I like, for reference, include Fizik Aliante, Airone, WTB Silverado)

  11. And in 2 years they will change it again.

    Give it up, Trek. Stop making mediocre accessories and focus on bikes. Or cleaning up the mess you helpedtomake with Lance.

    Here’s the thing… no one wants Bontrager stuff. Dealer stock it because they have to. They push it on riders that don’t know any better.

  12. 1. It’s sad that Bontrager has seemingly scrapped all of the wonderful research that they paid U of W researchers for. I guess their Inform line didn’t have the traction they were looking for.
    2. It seems obvious that they are following the market’s trend towards retro styling. It’s as if they said, “research be damned”.
    3. Those weights are terribly unimpressive for the cost of carbon. Is carbon just a “style” thing now? What’s the real advantage?

  13. Bontrager has been coming on strong recently. I have been riding one of their saddles for the past four years and I must say they have been great! I am excited about trying this new design!

  14. @seatsayer more than anything, carbon rails are there for added comfort. If you’re going to ask if you can really feel the difference, then I’ll let you know that you definitely can, since there’s a difference in how carbon rails are jointed together at the nose of the saddle vs. any metal rails. If weight’s a problem, then there’s plenty of full carbon 100 gram saddles out there that you can buy.

    @A. Pretty sure that Bontrager’s Aeolus D3’s are some of the most popular carbon race wheels on the market now, and that almost all of Bontrager’s current products have great reviews all across the web. Bontrager isn’t just a house brand of crap parts; Trek’s invested a ton in the brand in recent years (especially in their wheels) and their stuff is on par with many top companies out there nowadays.
    As far as bikes go, to say that Trek hasn’t focused on them is a pure sign of ignorance. They came out with the Domane, new Madone, new Speed Concept, new Fuel EX 29″, and redesigned most if not all of their 26″ mountain bikes into 650Bs since 2013. I could name more bikes that they came out with but you get the idea.

    *Also, newsflash here, Lance and Trek didn’t make the mess. The media did.

  15. Over the years I’ve had to replace a few Bontrager saddles due to crashes and vandals, but they haven’t worn out at an appreciably different rate than others.

  16. That’s all very nice, but Bontrager will be hearing from SPECIALIZED lawyers very soon, since they were going to use the name Serano on their next frame! HAH!

  17. Reminds me of my Selle Italia Flite 1990, my favorite saddle of all time. But with carbon rails. It has the right features, though, including the one that seems to be dying of neglect, side skirts. If they made it with a real leather cover I might buy one.

  18. I like the look of it, similar to a Fizik Aliante….but I’ll happily stick with my San Marco Regal which I’m sure will out last it as it has my previous Fizik’s…

What do you think?