The question always comes in the same form: “how many liters do I need?”. And it is the wrong question, because liters do not measure your luggage. They measure the container’s volume.
What really determines it is something else: how many nights you will be away and whether you sleep in a tent. From there, the number follows naturally.
The table that makes the choice easy
| How you travel | Volume |
|---|---|
| Weekend, two or three nights in a hotel or B&B, alone | 40 L |
| One week without camping, or a weekend for two | 50 L |
| One week with a tent and sleeping bag, or two weeks without camping | 66 L |
| Long self-sufficient trip: tent, sleeping mat, stove, changes of clothing | 90 L |
The practical rule that almost always works: a tent and sleeping bag alone are enough to move up one size. If your trip involves sleeping outdoors, choose the volume in the row above the one you would otherwise select.
Why choosing the large size here is not a mistake
With most tail bags, choosing the large size costs you every day: half-empty, it becomes a balloon that sways behind your back and catches the wind.
Here, the problem is solved mechanically by the front relief valve. After you close the roll-top, the valve expels excess air: the load is compressed and the bag adapts to the actual contents instead of its nominal volume. That is the technical reason why, with this range, you can choose a larger size without paying the price on days when you are carrying little.
One limitation remains that no valve can eliminate: a large, full bag is heavy and positioned far back. Ninety liters loaded to the top lighten the front end and are noticeable on the highway. The large volume is there to give you space when you need it, not to be filled all the time.
IPX6: what it means and what it does not mean
“Waterproof” on its own is not a specification. IPX6 is, and it means something precise: resistance to high-pressure water jets, including heavy rain, wheel spray, and washing. It does not mean resistance to immersion: that requires IPX7, which is a different rating.
For a bag that sits over the tail, IPX6 is exactly the right rating. Water from a ford does not reach beneath the seat.
The interesting part is how it achieves this. The body is made of technical PVC with high-frequency welded seams, without stitching. That is what separates a dry bag from a water-repellent bag: where no needle has passed through the fabric, there is no hole to seal. No heat-welded tape that peels off after two seasons, because there is nothing to tape.
The roll-top must be closed properly, otherwise the rating is meaningless
This is the note the manufacturer puts in writing and the main reason a waterproof bag gets its contents wet: the edge must be rolled for several complete turns and closed with both buckles. One turn only, or just one buckle fastened, and the stated waterproof rating no longer applies.
The closure is a patented magnetic roll-top: the magnets are embedded in the edge and fasten themselves as you roll it up. The advantage is noticeable when wearing winter gloves, which is the only time a closure is truly put to the test.
How to secure it
The manual documents three procedures. Two use the quick-release straps included in the package, attached to the fixed points on the sides of the tail section. The third passes the lid buckles through non-elastic third-party straps, if you prefer to keep using your own system.
Two cautions apply to all three methods, and they are the ones that prevent serious damage: keep the attachment points away from the exhaust and gather up any excess webbing, because a loose end that gets into the wheel or chain is the stupidest way to ruin a trip.
Color is not an aesthetic choice
The tail bag is the largest object a car sees of you when following you. On a loaded motorcycle, it is literally your rear surface.
The reflective inserts are on all sides, so black works at night. But during the day, in the rain or flat light, yellow or military green makes you visible in a way black cannot. If you ride many miles on the highway or in winter, it is worth thinking twice before choosing black out of habit.
The details you will actually use
- Separate dry and wet compartment. Your soaked rain gear and clean clothes do not share the same space. It is the feature you appreciate on the evening of the second day.
- Double side pockets for what you need without opening the main compartment.
- Detachable shoulder strap. Once you get off the motorcycle, it becomes a duffel bag: you can carry it to your room in one motion instead of going back and forth with your arms full.
How much does it cost
| Volume | Price |
|---|---|
| 40 L | 54 € |
| 50 L | 58,50 € |
| 66 L | 63 € |
| 90 L | 72 € |
There’s only a nine-euro difference between 40 and 66 liters. In other words: the step up in size costs less than a tank of fuel, which is why, when you’re unsure between two adjacent capacities, the larger one is almost always the better choice — the air-release valve brings it back down to the size of the load anyway.
See the waterproof rear case →
If you want to understand how it fits with the rest of your luggage — crash-bar bags, tank bag, side cases — the overview is here: semi-rigid cases and soft luggage.
Frequently asked questions
How many liters should a motorcycle rear bag hold?
40 liters for a solo weekend without camping, 50 for a week in a hotel or a weekend for two, 66 for a week with a tent, and 90 for long, self-sufficient trips. A tent and sleeping bag alone warrant moving up a size.
Does a half-empty 90-liter bag become bulky?
Not with this series: the front air-release valve expels air after the roll-top is closed, compressing the load so the bag adapts to its actual contents.
Does IPX6 mean I can submerge the bag?
No. IPX6 indicates resistance to high-pressure water jets, including heavy rain and splashes. Immersion requires an IPX7 rating.
Why do seamless welds matter?
Because every seam is a row of holes in the fabric and must be sealed with tapes that come unstuck over time. With high-frequency welding, the fabric is never pierced, so there are no infiltration points to maintain.
How do you attach a rear bag to a motorcycle?
Using the included quick-release straps, attach them to the fixed points on the sides of the tail section. The manual documents three procedures, one of which is compatible with non-elastic third-party straps. Keep the attachment points away from the exhaust and secure any excess webbing.
Do I need a luggage rack to mount it?
No. It rests on the passenger seat or luggage rack, if present, and only needs anchor points on the sides of the tail to which the straps can be attached.
Does the color affect anything besides aesthetics?
Yes. Reflective inserts are present on all sides in every color, but during the day, in rain or flat light, yellow and military green increase visibility compared with black.
If you’re unsure about your motorcycle’s capacity or anchor points, send us the make, model, and year: we’ll help before you order.
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