Let me start by asking you why you think they should be using it? Although the industry has largely gone to disc brakes, that doesn't mean they are a must and that doesn't mean they are faster. They are likely using the rim brake bike as that is the faster bike. Since the rim brake bike is not bound by UCI regulations, they are able to use lower seat stays and increase the area above the bottom bracket which help improve aerodynamics.

They made the disc bike for TT because the tri bike (which is faster) did not comply with UCI rules. Why would triathletes ride the slower bike?

TT bikes is not = Tri bike.
There are geometry rules and also things like internal storage, bento box etc. so it is for 2 seperate end users.

 
OK

Both have bento/hydration, similar geometry

C68 is not UCI legal, faster aero, a bit heavier, rim brakes
C68 TT is UCI legal, slower aero, lighter, disk brakes

If you are UCI bound, you must go C68 TT
if you are Triathlete, you choose C68 for flat tri (98% of Ironman courses), except if you train / races mostly in mountains and want disk brakes then you could go C68 TT.

This is more clear. Understand why Cube Tri Pro choose C68, as Kona, Roth, St Georges, Daytona, Florida, ............ are flat

The non-UCI disc version is like 40% more expensive than the TT version and is the 'premium' option if you will. Cube can't put their UCI-teams on the bike why would they build and sell a more expensive version of the bike and not force their Tri-athletes on it?

Personally I don't like hydraulic rim brakes as you kind of get the worst of worlds and I wouldn't pay £4k extra just for some BB storage. So if its my money I'm going TT and I suspect Cube know this which is why they still put a massive bento box and hydration system on the 'TT version'. That isn't to say the rim bike isn't faster its just not going to be for everyone especially at its superbike price.

There is no BB storage on either of these bikes

Well that makes the Tri version even more confusing. I had assumed there was storage just based on the frame shape but on the reflection to fairing at the BB does look very thin.

I remain unconvinced on the merits of of hydraulics rim brakes but that is my issue not Cubes. In any case it remains an lofty price point given if a buyer wants to spend that much they are spoilt for options.

I don't get your point on price at all. The Aerium retails for 3800€ including storage, cockpit, and both Magura brakes. It's one of the best values on the market.

The prices in pounds are then way out of wack with the euro prices. The arium is coming up to me as £11099 as a full build or £3600 for the frame set. That’s like 4300 euros frameset only.

When folks get into tri or TT, these days at least, they should have to read a little FYI where they click a checkbox acknowledging they read this and understand this.

Before I got a Trinity, Pro TT, I kept getting mad opening ads for "Shiv TT" bikes that were clearly the integrated hydration triathlon bikes. Same for other brands. It got quite annoying. Even vendors selling used bikes were getting it wrong.

I'm very interested in the Cube Aerium c:68 TT bike as well. The 2023 model with disc brakes, Ultegra di2 and good aero wheelset sells at a discount for 6300 EUR. This is 2200 EUR less than the canyon speedmax cf slx 8 di2.

I only do triathlon and I'm mainly interested in a comfortable and fast bike to step up to the long distance. My current triathlon bike is actually a BMC Timemachine road retrofitted for triathlon so anything would be an upgrade and would be more comfortable for me 😅

The main issue with this bike is the TT seatpost pointing backwards, but I'm assuming I can use the triathlon seatpost sells for around 200 - 300 EUR.

Apart from this, would you still consider this bike and is it worth spending 2200 EUR extra for the Canyon speedmax cf slx 8 di2?

Especially that the cube aerium c:68 TT is also available with interest free financing.

I know the canyon cf slx has a superior cockpit, clean integrated hydration and storage options (in frame bento and toolbox), alongside the left side power meter. But I already have a dual side power meter.

I'm also considering the CF SLX 7 Sram rival, but it comes with cheaper wheelset, both front and rear are 62mm. It costs 6800 EUR, but it's not in stock at least in my size for a long time.


Thoughts?

Cube recently released the C68X which is more than a match for the Speedmax in terms of storage and hydration options. Maybe that one will fit your needs better than the TT version?

Yes looking at this one as well. It's not available yet, probably early 2024. And for 7800 EUR the cheapest option 😅

Don't bother.
My wife ordered one (Cube Aerium c:68 TT w. disc brakes) in January for delivery in May, which became June, which turned into August. When it got pushed to October, LBS out of pure compassion offered to cancel the order, buy the frame and custom build it.
Frameset arrived with seat post missing. Ordered seat post, still waiting.
Save yourself the headaches and buy a bike from a reliable company.

I'm located in Germany, and the bike seems to be available and ready to ship from multiple stores.

Good luck