Topeak BackLoader 15L 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 BackLoader 15L takes weight; the BackLoader X 15L takes how far it reaches back and tire clearance. 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
3 of the 6 things we can measure come out differently.
Reach behind the saddle
16cm shorter on the BackLoader X 15LLength is the lever arm on the seatpost, and the longer lever is what makes a loaded pack sway. Shorter is easier to live with; longer usually means more volume. It is a trade, not a fault.
Depth
4cm shallower on the BackLoader X 15LDepth 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
40g lighter on the BackLoader 15LEmpty weight as published. Worth holding against capacity rather than alone — the lighter bag is not the better one if it carries a third less.
Side by side
Including the rows where they are level.
| Topeak BackLoader 15L | Topeak BackLoader X 15L | |
|---|---|---|
| Capacity | 15L | 15L |
| Reach behind the saddle | 67cm | 51cm |
| Depth | 28cm | 24cm |
| Weight | 565g | 605g |
| Price | $123 | $130 |
| Per litre | $8.20 | $8.67 |