As of now the USAT rules make no mention of demensions i.e. 30 x 30, 250mm, etc. as per a pdf link on this page USA Triathlon | Multisport Rules that indicates it was updated on 5/16/25.
They do put a 2L limit on the front and 2 1L bottle limit on the back (not sure how that impacts the most recent Shiv with in more that 1L.
Here is the excerpt:
h) Hydration bottles or hydration systems exceeding the following volume limits:
i. Front-mounted: Bottles or systems mounted to components that rotate
around the steering axis (e.g. cockpit extensions, base bar) have a
combined maximum capacity of 2 liters. (Note: Water bottles may not be
placed on handlebars in Draft-Legal races. See Sections 4.7.1.1.h. /
4.7.2.1.h.)
ii. Rear-mounted: Bottles or systems not mounted inside the triangle bicycle
frame cannot contain more than two bottles and cannot exceed a capacity
of 1 liter per bottle. (Note: Water bottles may not be placed behind the
saddle in Draft-Legal races. See Sections 4.7.1.1.h. / 4.7.2.1.h.)
And from that:
â1.1 e) The rules outlined in this document are underpinned by the World Triathlon
Competition Rules.â
I assume interpretations issued by World Tri will be followed given that the USAT Rules are underpinned by the World Triathlon Competition Rules.
Iâm certain that USAT will give clear guidance on how they will approach this.
Did not see that reference. Thanks. Looked for the green highlights for new rules of which the excerpted text was a subset.
What doesnât make sense then is why go into detail about the volume limits and not the rest of the new World Triathlon rules.
No, you have it correct: the USAT Rules almost exactly replicate the World Tri Rules (they have improved the wording). What USAT donât have yet (and imho donât actually need) is the German inspired âinterpretationâ doc (linked above).
If USAT just enforce the basic rules as stated (maxs 2 liters front, 2 bottles/liters rear, any amount inside frame or inside triangle, non-hydration box on seat tube/post matters not) all will be fine.
FWIW, I e-mailed the USAT rules comissioner a few weeks ago, asking if the WT fairings rule would be enforced in August at the Age Group Nationals. No reply yet, but his autoreply states heâs been out supporting T100 Sanfran and then the Omaha multisport festival. Iâll forward a reply, if I get one.
Isnât your starting point a little too far forward (at least a few cm)? Her elbows are sitting pretty far forward from the edge of the cups which is where you would measure from since its the lowest edge of the arm support.
Could be and btw this is from an insta image Trek shared.
We discussed up thread that the âlowest edge of the armrestâ could be gamed by extending to the rear the full forearm rest and making that extension (which has no function) a little lower than under the elbow.
From a ârule enforcerâ PoV I would eliminate that extension as it is not longer âthe armrestâ and set the datum reference point directly under the point of the elbow in its natural aero position (âlowest edge of the armrestâ).
More broadly I donât see why this rearward limit needs to be set (remember this is not in the rules themself but in the fevered Germanic enthusiasm of the DTU, which World Triathlon have failed to moderate in an adult way.
As for height, if indeed it has merit at all, Iâd use the top of the base bar as a (simple) datum reference point (but I guess there are complications if that was adopted).
I was wondering this with my Carbon Wasp extensions. The end of my actual elbow is at least 4cm forward of the back of the extension. So having them measured from the lowest edge of the arm support gives me far more room to fit a bottle than where my elbow sits in position.
Handy for me, I suppose but seems an easy workaround for manufactures going forward. Just add length to the back, even if the rider wonât use it.
How do you police that though? Do you have a ref following athletes while riding and eye-balling 250cm? At bike check-in, I would be showing them that I rest my elbows as far rearward as the pads go. Even if I ride 1-2cm forward from the rear of the pad in reality.
At bike check-in, I would ask the athlete to hold the grips, rest their forearm and that will determine where their elbow lies: and take it from there. And be sensible with tolerances (<250mm rearwards, but actually just where the bottle base is (given 250mm long 750ml reference bottle, assumes normal cage).
I could game that too by showing I shift with my index or pointer fingers vs thumbs.
If they are going to be steadfast on the rule, I would rather them just pick a fixed point to measure from regardless of the arm pad/cup setup. Like the center of the steering axis and top tube.
The easiest one is the point at which the steering column pivots vs the top tube (the first portion which is able to move). The centre point takes more time to measure from, and they have rules which already reference this point in the top tube rules.
Iâm good with that
World Tri have yet again revised the interpretation document (and published it on 12th June with regard to storage boxes mounted behind the seat tube (no fanfare). This, btw, is how Roth stated it would interpret the World Tri rules many weeks ago.
Triathlon magazine:
Ende in Sicht? Eine erneute Anpassung der Regeln erlaubt Werkzeugboxen am Heck kĂŒnftig ohne GröĂenbeschrĂ€nkung. Ein Schritt in die richtige Richtung.
Translation: End in sight? In the future, tool boxes at the rear will allow a further adjustment of the rules without size restrictions. A step in the right direction.
I submit an example of a ârear mounted storage box(es) that are able to contain tubes, CO2, tire levers, and other tools necessary for basic maintenanceâ.
How is it possible that one organization is so incapable of writing rules unable to be immediately exploited.
(yes I know itâs a recumbent but you get the idea)
You and I both know that would immediately get shitcanned under the catchall of ârefereeâs discretion.â
I think this is also a case of not trying to be the UCI. Although thatâs probably closer to where we are headed.
Yes, of course it would be at refâs discretion. But what about one thatâs 10% smaller? 50% smaller? 90% smaller? The line needs to be drawn somewhere. It needs to be a fixed dimension, but a fixed dimension that is inclusive of body sizes, bike builds, current equipment and what tradition they are trying to uphold.
The UCI, for all of their faults, did it on a few different occasions. For the most part theyâll say any bike made prior to this rule change is grandfathered in, but not always. It could be more challenging the modern era with the prevalence of aftermarket parts, but thatâs not unsolvable. List out the specific 5-10 brands that produced bikes afoul of the new rules and let them be used. New tech will surpass them in a few years anyway.
Or, even better, have a third category between AG and Pro where the strict rules apply. Not many non-safety rules for AG/Open, strict rules for Pro/âEliteâ.
Iâm glad they havenât gone down that overly specific route.
If you push the bounds you do it intentionally and willingly and know you are risking having your set-up rejected by the ref. Be reasonable and you donât have that risk.
Who defines reasonable, especially on edge cases? Personally I think Dimond bikes look unreasonable with the big fin behind the front wheel, yet theyâre allowed.