Revelate Designs Spinelock 16 Seat Bag vs Topeak BackLoader X 15L

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

The short answer

The Spinelock 16 Seat Bag takes capacity, tire clearance and weight; the BackLoader X 15L takes price. Which of those you care about depends on the frame you are fitting it to.

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

4 of the 6 things we can measure come out differently.

Capacity

1L more in the Spinelock 16 Seat Bag
Revelate Designs Spinelock 16 Seat Bag
16L
Topeak BackLoader X 15L
15L

The maker's own figure. Worth reading alongside the dimensions below rather than on its own — two bags of the same litreage can want very different frames.

Depth

2cm shallower on the Spinelock 16 Seat Bag
Revelate Designs Spinelock 16 Seat Bag
22cm
Topeak BackLoader X 15L
24cm

Depth is what competes with the rear tire once the pack sags under load. On a small frame or a big tire this is the measurement that decides it.

Weight

210g lighter on the Spinelock 16 Seat Bag
Revelate Designs Spinelock 16 Seat Bag
395g
Topeak BackLoader X 15L
605g

Empty weight as published. Worth holding against capacity rather than alone — the lighter bag is not the better one if it carries a third less.

Price

$40 between them
Revelate Designs Spinelock 16 Seat Bag
$170
Topeak BackLoader X 15L
$130

Manufacturer's price as we hold it.

Side by side

Including the rows where they are level.

Revelate Designs Spinelock 16 Seat BagTopeak BackLoader X 15L
Capacity16L15L
Reach behind the saddle50cm51cm
Depth22cm24cm
Weight395g605g
Price$170$130
Per litre$10.63$8.67
Revelate Designs
Spinelock 16 Seat Bag
$170 · 395g
Topeak
BackLoader X 15L
$130 · 605g

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