Bontrager Aeolus 9 TLR D3 Clincher – Review

It’s surprising to see the different reactions each of our editors make whenever a box shows up at AeroGeeks HQ. For some products, it’s extreme giddiness, excitement, and maybe a little jealousy if they won’t be the ones testing that particular product. For other products, it could be concern as we start to wonder exactly how many miles we will need to put on a product in order to be comfortable sharing our thoughts. And every once in a while, the reaction is one of trepidation – do we really want to risk our training miles testing this? Now for a wheel review, you might be surprised that there would be trepidation in the first place. Come on, it’s just a wheel, right? After all, our regular readers know we have tested plenty. But the Bontrager Aeolus 9 TLR D3 can be run tubeless, and that is a whole new ball game for us triathletes.

The Bontrager Aeolus 9 TLR D3 Clincher

Bontrager is no stranger to wheels, and their Aeolus TLR D3 line is their best of the best. We previously tested the Aeolus 3 D3 (pre-TLR model) and came away all smiles. The new version takes everything Bontrager learned from the original, then sheds some weight and adds Tubeless Ready (TLR) abilities.


The Aeolus 9 TLR D3 starts with OCLV carbon – Trek\Bontrager’s top-end carbon. Manufacturing takes place in Waterloo, Wisconsin – race wheels are built in the same building as those found on the rack at your local transition.  The Aeolus 9 are 90mm deep, with a 27mm outer width and 19.5mm inner (the previous generation had a 17.5mm internal). They are built around DT Swiss hubs and are Shimano/SRAM 10/11 compatible (a Campagnolo freehub is sold separately). The pair weigh in at a claimed 1,812g. This is a noticeable improvement from the prior Aeolus 9 D3.

The wheels ship with cork pads, TLR rim strip, TLR valve stem, and a quick release skewer. Though considering this is Bontrager’s top-of-the-line wheel, we expected a slightly nicer skewer – it’s the small things.


The newest iteration of the Aeolus lineup has been built in partnership with Trek Factory Racing. Pro riders were riding on the new D3 long before consumers got a chance to sample them, and they helped validate an additional braking option – Swissstop’s Black Prince pads, which now can be had from your local Bontrager dealer as well.

TLR – Tubeless Ready

So you may be asking, why tubeless?  Do triathletes really need this? Well, Bontrager is not the only one that has been hopping on the tubeless bus. Easton’s EC Aero 55 wheels offer it as an option, and Silca has been promoting a number of tubeless ready products and add-ons. But just because companies are making it doesn’t always mean we need it (feel free to start the disc brake debate in the comments).


But tubeless offers a number of advantages that triathletes should find pretty useful. First is the absence of pinch flats – no inner tube means no flats. Tubeless with sealant also gives additional flat protection. While we are jumping ahead here, we never experienced a single flat while putting a few thousand miles on our review set. Tubeless also allows you to run lower pressure, which results in additional comfort. We typically rode around 100 psi but know many who routinely go down to 80psi. For those looking to spent 4-6 hours in their aerobars, anything that provides even the smallest measure of additional comfort is readily welcome.

Finally rolling resistance tests are now routinely showing that removing the innertube shows a measurable improvement in rolling resistance. ( The only bad news here is that there are few, if any, aero tires on the market that are tubeless ready. Bontrager makes the excellent R4 aero tire, but only the R3 can go tubeless. Bontrager, if you are reading this, we want a tubeless R4 aero!

So what does it take to setup your Aeolus rims for tubeless? First – watch the video below.

Alright, now watch it again. And if you are like us, you will end up watching it another 2-3 times. For those not inclined to watch, here is the short version. Tubeless requires the installation of a rim strip to prevent air leaking through the spoke holes. Next come removable valve cores that are installed onto the rim. Next, seat the tire and add the sealant. Bontrager sent us both a giant bottle of sealant with a reusable syringe, and a number of little bottles as well. We ended up finding the little bottles much simpler to use (be sure to shake the bottles well before applying).


Finally, it’s time to inflate. Without an inner tube to push against the side walls you need to quickly push air into the tire to hold pressure against the sidewall. This is easiest with a compressor, though a track pump can work fine as well. Bontrager sent us their FlashCharger pump which has a built in air reservoir that you can pump up and then dump into the tire to quickly seat it (think of this as a compromise between the air compressor and your standard track pump). In our time with the TLR, we actually used a standard Bontrager SuperCharger (no air reservoir) 90% of the time. The only exceptions being the first time we seated the tires – we figured since Bontrager sent us the FlashCharger we should use it. Oh, and there was one other instance…


You see for a few months we stopped riding the Aeolus 9s. We had a few reviews that jumped the queue – both new bikes with their own included wheels and some wheel reviews that required specific timing. Because of this, our Aeolus 9s sat unloved in a corner for some time. The tires lost pressure, the sealant leaked out, and we had quite a mess on our hands. Once time was again on the Aeolus 9’s side, we had to set to work cleaning them up, removing the old sealant, and reseating them on the rim. For whatever reason, neither FlashCharger or SuperCharger could reseat them. We had to resort to an air compressor to get them mounted (but luckily almost any LBS will have one if you need the extra hand).

Our Thoughts

Let’s start with Tubeless. Is triathlon ready for it? In our opinion – hell yes! After almost a year with the Aeolus 9 D3 TLRs, our biggest complaint has been there is no full disc option (though Dash recently launched a tubeless ready Gretchen Disc that should solve that). We never experienced a single flat or failure while riding tubeless. Every once in a while we would hear a slight hiss from the tires and then silence. We knew the sealant had done its job and we were good to go.


As we mentioned earlier, we had a lot of trepidation riding tubeless. To the extent that, in the beginning, we always carried not only a tube in our spare kit, but a complete tire in our back pocket. But tubeless has won us over. Our one and only concern now is a giant gash on race day. With a standard inner tube in that type of scenario you can use a business card (or even a Cliff bar wrapper) to block the puncture and then stick another tube inside. If you are running tubeless, that is not an option. But in our opinion, that is a risk we could take since the more likely scenario is a small puncture that standard sealant could handle.

Riding the D3s we found them to hold up consistently with other wheels in the class. We rode front and rear 90mm wheels, and while the editor that did most of the riding is no light weight, (85 kilos) he never had any cross wind stability issues.


Bontrager had previously shared a whitepaper for the original D3 shape, and they tell us the results still hold true today – these are some of the fastest wheels on the market. With the original D3 line Bontrager engineers set out to design a wheel that would optimize performance in both the tire-leading and rim-leading positions—and Dual Directional Design, or D3, was born.


Braking was our one major issue with these wheels. Braking with the included cork pads just wasn’t up to some of the recent options from Zipp and Reynolds – and that was in the dry. If the wheels were wet, things went downhill quickly. We also encountered major squealing when braking. We reached out to Bontrager, and they sent us a second set of cork pads plus their newly optional Black Prince pads. We skipped the cork pads and went straight to the Black Prince – what a difference. Braking noise was greatly reduced and stopping power went up considerably, especially in the wet. Bontrager says that the Black Prince pads are harsher on the braking surface of the wheel and should be only used for wet days, but we will be taking that risk and sticking with the Black Prince pads.


The biggest challenge for buyers thinking about these wheels may be the price tag. At $2,598 these are not cheap wheels. And unfortunately the name Bontrager does not have the same coffee shop appeal that Zipp, Enve, and others have. But those in the know, know that Bontrager Wheel Works has been around a VERY long time and know a thing or two about making wheels. And those that only care about the name on the side of the gear are probably not the ones standing higher than you on the podium.

Wrapping Up

We really like these wheels. So much so that Bontrager may have a tough time getting these back from us. We think Tubeless is not only coming but will be here to stay when that time comes. It has almost none of the hassles of tubular tires with most of the benefits of clinchers. We would call it a compromise but it is more a best of both worlds. Really we want just two things from Bontrager when it comes to these wheels – a set of R4 aero tubeless tires and a full tubeless disc. But until then we will be more than happy to keep riding on our Bontrager Aeolus 9 TLR D3 Clinchers and doing our best to avoid the Bontrager repo men showing up on our front doors.

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