Outdoor Research Helium Bivy vs Six Moon Designs Lunar Solo

Two shelters, measured against each other on the figures that decide whether they work on a bike.

The short answer

The Helium Bivy takes weight; the Lunar Solo takes floor space, vestibule space and price. On a bike the pole set usually decides it before the rest do.

Assembled from the differences below rather than written over them. Every figure is a published measurement or computed from one — nobody here has used either one.

Where they differ

5 of the 5 things we can measure come out differently.

Poles to carry

the Lunar Solo has no pole set at all, the Helium Bivy does
Outdoor Research Helium Bivy
311mm folded
Six Moon Designs Lunar Solo
None — trekking-pole shelter

A trekking-pole shelter has nothing to fit across your bars, which removes the constraint entirely — but you then need poles from somewhere, strapped to the frame or bought separately. It is a different problem, not a smaller one.

Minimum weight

229g lighter on the Helium Bivy
Outdoor Research Helium Bivy
511g
Six Moon Designs Lunar Solo
740g

Trail weight where the maker publishes one — fly, inner and poles, without the stuff sacks or the footprint. Worth reading against the pole length rather than instead of it: a Bikepack edition is usually a few grams heavier for shorter poles.

Floor area

1.28m² more floor in the Lunar Solo
Outdoor Research Helium Bivy
208 × 71cm — 1.48m²
Six Moon Designs Lunar Solo
228 × 121cm — 2.76m²

Inner length by inner width as published. On a bike trip the floor also has to take whatever you brought inside off the bike, so a few centimetres is not nothing.

Vestibules

1 more on the Lunar Solo
Outdoor Research Helium Bivy
0
Six Moon Designs Lunar Solo
1 — 0.8 cm²

Where wet kit and panniers go. On a bike trip it is also where the bags off your bike spend the night, which is more volume than a hiker brings.

Price

$35 between them
Outdoor Research Helium Bivy
$250
Six Moon Designs Lunar Solo
$215

As we hold it. Shelter prices move more than most gear, so check before you commit.

Side by side

Including the rows where they are level.

Outdoor Research Helium BivySix Moon Designs Lunar Solo
Poles to carry311mm foldedNone — trekking-pole shelter
Minimum weight511g740g
Floor area208 × 71cm — 1.48m²228 × 121cm — 2.76m²
Vestibules01 — 0.8 cm²
Price$250$215
Outdoor Research
Helium Bivy
$250 · 510g
Six Moon Designs
Lunar Solo
$215 · 740g

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