It would come down to haw big that behind that saddle mount is? is it greater than 30cm in any direction (including the boittle cage but not the bottle)?
If yes - you need a new mount,
If no - you are ok. My reading of the rules (per above is that) your integrated hydration is “inframe” not behind frame so you are allowed rear bottles
Yea with regards to a frame with a internal bladder (not rear) and a rear storage box my read is this:
If the box is integrated (QR) and exceeds the 30x30 frame (not saying this is true for the QR as i don’t have one to measure - no bottles in rear.
If not rear storage is ok - but it and the bottle mounts have to be with in the 30x 30 frame - see the bold part at the end below
" Aero storage box/drink container/storage bags at the rear - As long as all mounts, containers, bottle cages, etc., are within an imaginary 30 x 30 cm frame, they are permitted. Only the bike bottles themselves may extend beyond this. Regarding dimensions, the dimensions for beverage containers (except standard bike bottles) must be within 30 x 30 cm.
Exactly. My Ventum One holds 1.5. WTH couldn’t I add a .5 liter bottle on the back? I understand the handlebar load, but why not just come with an overall capacity limit while complying with the handlebar rules.
I think the net result of all this is that someone is going to start work on a 2L front mounted hydration system that meets all these specs and is generally aero positive for most people. And frankly, I’m here for it.
If people read the rules carefully there would be less outrage
As written with a ventum you are allowed to put 2L of water behind the saddle.
Again the no bottles behind the saddle only applies to integrated hydration located behind the saddle (the AND is very important). To my knowledge only the Shiv is affected - so lets call this the shiv exception
Safety rules provided to you by: Mortal Hydration.
Ryan’s article clearly says that any bike with built-in hydration cannot have rear bottles.
It also seems to impact QR which is why I’m a little surprised IM would fully adopt the rule as it pertains to the rear storage/hydration. Seems it would also likely impact people who purchased customer rear storage like this 2021+ Canyon Speedmax CF 7/8 Disc Rear Box. Though maybe it could be squeezed into the 30x30box with the right set-up.
This is exactly the case. Everybody’s getting hung up on the rear 30x30 box but there’s little difference between rear mounted systems. It’s in such turbulent air and mechanically separated from the rider. You can’t really set up a bottle fairing on the riders butt without limiting saddle position.
The front box is defined by the back of the armrests, but there’s no rule about his far back armrests can extend. So the logical first move is making super long armrests to extend the box
Yes - but his article is wrong by the letters of the full rules as spelled out by WTC
Can you provide a link to the actual document? I’ve tried to find it but havent had any luck
Yes it/he says that.
But the new rules say (my emboldening):
Exception rear
– Hydration - Systems integrated in the frame:
o may be larger than 30 x 30 cm,
o may not contain more than 2 litres in total,
o must not protrude beyond the vertical line through the rear axle.
o On bicycles with hydration systems that are integrated into the frame [this section is talking about ‘rear’] no additional attachments may be added to the rear of the frame.
“Rear Hydration Systems integrated in the (rear of the) frame may be larger than 30 x 30 cm.”
The fact that the (side) area is defined allows us/me to say that this is behind BB “integrated into the frame”.
So no bottles there if the inside the frame bladder is at the rear of the bike.
SO I have been following through DTU - which started these meeting to get alignment after there was new rules for roth that were extremely limiting.
They have been updating as they met this ironman and WTC on their instagram and put out the full new rule document a few weeks ago that WTC now adopted.
You’ll have to do some translation (unless you speak German) but it starts on page 19 https://www.triathlondeutschland.de/sites/default/files/documents/2025-04/Sportordnung%202025_0.pdf
Full specs page 79
I also think the provided diagram makes this pretty clear
Hey, what rear mount kit is this? I’m interested. And … very nice bike set up!
The original text did not include it specifically talking about rear hydration. That has been updated since yesterday’s article.
For whatever it’s worth, the IRONMAN rules were more clear about this from the get-go on rear hydration.
It’s our understanding that the updated rules for IM events will come into effect no later than Hamburg.
Thank you. The sadle bottle holder, is a piece i made together with rockerplates.de
I don’t know if it is up for sale yet.
Welp.
Just a heads up if you’re using one of these new TriRig BTA Elevator things, it might be hard to make it comply with these new rules.
Just measured my setup and it’s right on the edge both in height and rear space length. Definitely going to depend on where the pads are mounting relative to the elevator. I’ll probably just slide my pads back 10mm and add 10mm of random spacer underneath if Ironman actually ends up enforcing this. The graphic displayed above also makes it look like there is a max height for the shifters as well, but I think they’re just showing that as a the box for hydration?
What about Scott Plasma 6? It has 2 integrated frame bottle and tool storage behind the seat post.
