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263craft

Carbonology · Flatwater trainer

Carbonology Ultra X LV (K1)

The Ultra K1 at lower volume: same 5.2 m length, 39 cm instead of 41 cm, front deck down from 29.5 cm to 27.5 cm and back deck from 25 cm to 23 cm. Same platform seat, under-stern rudder, splash lip and optional pump. Rated 50-80 kg against the Ultra’s 75-100 kg.

Length
5.2 m
Beam
39 cm
Deck
35.4 cm
Lightest
8 kg
Source image flipped
 
Carbonology Ultra X LV (K1), studio hero/full craft
studio hero/full craft · carbonologysport.com

Specifications

Length
5.2 m
Beam
39 cm
Deck height
35.4 cm (est.)
Category
Flatwater trainer
Usually paddled by
Confident ocean paddlers
New price
A$3,375

Layup weights

River Glass Vacuum11 kg
Hybrid9 kg
Carbon8 kg
Carbon Wood Inlay8 kg

On-water profile

Stability
1–4
Editorial estimateLow confidence
Speed
9

Our estimate from published descriptions and reviews. Low confidence. Speed is our rating. Both are given at the hull's own design weight.

These ratings are Surfski Index estimates, worked out from published dimensions, traced hull shapes where we have them, and reviews. They are not supplied by the maker or timed on the water. How a ski feels depends on your weight, skill, set-up and the conditions, so use them to shortlist skis and paddle one before you buy. How we rate.

Stability here means how steady the ski feels sitting still on flat water. Where two craft have overlapping ranges, we can't say which is more stable. Downwind handling is a separate thing, covered in the evidence note below.

Evidence note

This band is a cautious editorial estimate; it is not backed by a hull trace. Qualitative context includes 3 linked sources.

Suits: Flatwater racing and marathon for paddlers roughly 50-80 kg. Not an ocean craft.

Paddler weight

Carbonology rates this hull for paddlers from 50 kg to 80 kg.

The maker’s published range. How this is worked out.

Generations

2017-

Low-volume Ultra for lighter paddlers, 2 cm narrower with both decks dropped.

Pros and cons

Pros

  • Genuine low-volume K1 for a light paddler, not just a narrower one
  • Same price as the standard Ultra
  • Down-river build available

Cons

  • Not a surfski: needs a spray deck
  • Band tops out around 80 kg
  • No independent review or owner report

Where to buy

Carbonology Sport ↗

Dealers:

Ocean Paddler · AU ↗Australian Paddle Sports · AU ↗Ocean Paddlesports · AU ↗PaddleZone · AU ↗

Australian Paddle Sports 2026: River build (11 kg) A$3,375, Hybrid (9 kg) A$3,475, Carbon (8 kg) A$4,100, Carbon Wood Inlay (8 kg) A$5,500. Priced identically to the full-volume Ultra.

Sources

BetaRatings are estimatesRatings are estimates. How we get the numbers. Prices checked October 2026, may be out of date.