Blackburn Outpost Frame Bag (Medium) Review
The Outpost is a half-frame bag that sits between the budget wedges and the full-frame bags. Its case is capacity that expands when needed and the strongest owner record of the three here.
The verdictThe best-supported half-frame bag of its price, with expanding capacity. Check bottle clearance on smaller frames before buying.
The Amazon link opens on the Medium, which Blackburn's size chart gives as 4.3 litres, or 5.8 litres with the base expanded. The Small runs from 2 to 3.5 litres and the Large from 5.25 to 6.95. The fabric is coated 70D ripstop, water resistant rather than waterproof, and the bag has a hydration port.
Owners describe a left-side pocket, a right-side main compartment with a divider and stretch pockets, so it opens from both sides. That layout keeps heavy tools low and snacks reachable. The expanding base is the useful trick, because it adds capacity for a trip and folds away for a day ride.
Fit is the thing to check. One owner fitted the Medium to a 52 cm road bike but had to move the down-tube cage lower, another found even the Small blocked the bottles on a 48 cm frame, and a Large owner says it needs about 19 inches along the top tube. Hook-and-loop straps marked one owner's paint, so protect the contact points.
Owners on Amazon US gave it 4.7 stars from 885 ratings in October, with about 2 percent at one or two stars. Retailers list a limited warranty. At its August price it costs about twice a budget wedge, for more capacity and a better owner record.
What works
- Expands from 4.3 to 5.8 L in the Medium
- Opens from both sides, with a divider
- 4.7 stars from 885 owners
What doesn't
- Can crowd bottles on smaller frames
- Water resistant, not waterproof
- Straps can mark paint
Buy it if
Riders who want more than a wedge holds while keeping a bottle cage, on a medium or larger frame
Skip it if
You ride a small frame where any half-frame bag blocks the bottles, or need a waterproof bag
Others we scored in this category
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