Buying a frame bag

Thinking of Buying a Frame Bag?

Buying a frame bag for your bike can be a daunting task. Half frame bag or full frame bag? How many zips and pockets? Colours? Here I consider all these questions and more and make deciding on your first bag as easy as riding a bike.

Full Frame or Half Frame?

This is probably the first question you need to think about when looking to buy a frame bag.

Half Frame - If your frame is large enough you could choose to have a half frame bag as seen in the image below. For cyclocross and road bikes I prefer the look of a half frame bag. In most cases you can fit a decent sized half frame bag and still use the bottle cages. 

Half frame bag with bottle cages
Half frame bag with bottle cages

Full Frame - Personally I think that for most mountain bikes you are better off with choosing a full frame bag (see the image below). The space gained by using a full frame bag is substantial and you can still carry water bottles inside the bag if need be.

Full Frame Bag on bike
Full frame bag. Double zip/compartment

Zips and Pockets?

Getting the right combination of zips and pockets can significantly enhance your frame bag experience. The three most popular options are described below.

Single Zip - One Large Compartment

Having a single zip is a good, simple option (see image below). It creates an open space in which to store both your small and the slightly larger items. A single zip opens into one large compartment, utilising the whole inside space of the bag. This is generally a good option for small and medium mountain bikes. On larger frames, you will need to consider whether the bag is likely to bulge out and whether you would like a Velcro divider to mitigate this (dependent on what you plan to carry in your bag – see note below).

A note on bulging reduction: velcro dividers can be used to connect the two main side panels of the bag and manage the bulging that can occur in bigger single zip bags. In a single zip bag, a good place for a divider is about 10cm in front of the seat tube, this is generally the widest point of the bag.

If purchasing a double zip/compartment bag (see below) then a divider is fitted as standard to separate the two compartments, but also acts as a restrictor to reduce bulging.

Single zip full frame bag tan
Single zip full frame bag

Double Zip - Two Compartments with a Horizontal Divider

The double zip, double compartment option is worth considering if you have a larger frame or want to keep the contents of the bag a bit more organised or separated (see first image below). The upper zip opens into an upper compartment while the lower zip opens into a lower compartment. The compartments are separated by two velcro panels that are sewn into the sides of the bag just above the lower zip (see second and third images below). When these two panels of velcro are attached they create a false floor and divider between the two compartments. If you do want to use the bag as just one big compartment, then you can just separate the panels and they will naturally sit against the side of the bag.

Double zip compartment full frame bag
Double zip/compartment full frame bag

Frame bag divider open
Frame bag divider open

Frame bag horizontal divider closed
Frame bag horizontal divider closed

Flat Map Pocket - Additional to Either of the Above

I would highly recommend this option. The map pocket is a great place to keep maps or items such as your phone to ensure they do not get lost or damaged in the main compartment (see image below). It is essentially a two-dimensional space and therefore is ideal for carrying thinner items. The pocket sits between the exterior fabric and the liner fabric of the main compartment. It is accessed from the exterior of the bag, on the opposite side to the main compartment zip. A map pocket can be added to any bag. 

Frame bag flat map pocket
Flat pocket shown with phone

Hydration Bladder Hose or Cable Port

If you plan on using a hydration bladder or have lights with external batteries this is a useful addition (see image below). The H20 port gives you a clean way to run cables and tubes from the outside into the inside of the bag. 

Frame bag H20 cable port
H20 Port with light battery cable

Bag Width

The standard bag width (empty) is 8cm. However, some people have requested a narrower bag if their knees tend to roll in. Others have requested a wider bag for that little bit extra capacity. If you think you may like a custom width, let’s chat about the pros and cons and find the best option for you.


You can choose the main colour for the side panels of the bag (see available colours in the image below). If you would like more than one colour on the side panels (see images below), that is no problem. It will just be a small extra charge as there is a bit more work involved. The colour for the attachment panel (the part against the frame) is black, this is the only colour I carry that is suitable for this part of the bag. 

Frame bag colour options
Multi-colour frame bag

Colour chart
Current colour options. Click for full resolution.

Reflective Strips

If you ride a lot at night, and especially on the road, then adding reflective to your bag should definitely be considered (see image below). Reflective vinyl can be heat pressed onto the bag prior to construction. The reflective vinyl has a nice matte silver appearance during the day but as night falls and the lights come out it shines bright keeping you seen and safe.

Single zip frame bag with reflective stripe
Reflective strips on single zip frame bag

Frame Attachments

For most frame bags I have kept with the trusty attachment system I have had since 2014. There is a strip of webbing around the perimeter panel of the bag which is bar-tacked to the fabric every 40mm (see image below). The perimeter fabric has a polypropylene sheet in between the liner and exterior fabric which gives the bag structure and distributes the load. Double-sided micro hook and loop (Velcro) is then fed through this daisy chain of webbing so that you can attach the bag to the frame where it is best suited (this will vary depending on the bike).

This creates a mounting system that is easy to use, modular and replaceable (velcro does wear out!). Because of the even load distribution, there are no stress points on the zips meaning they are easy to open and close and will last a lot longer than bags where the velcro is sewn directly into the seam.  

Daisy chain velcro attachments
Durable and adjustable daisy chain frame attachments

Another option is to use the bottle cage mounting bolts or other threaded points to hard mount the frame bag. This gives a nice clean look, but a precision template is needed with bolt locations. The bag in the image below has standard daisy chain Velcro attachment on the top tube and is bolted on to the bottle cage mounts on the downtube and seat tube.

Partial bolt on frame bag
Full frame bag with bolt on attachmnet to down tube.

Other Options

There are still many other options that I have not covered here, mainly to keep it simple and brief. Roll Top frame bags, small “enduro” bags, Panel loading frame bags, just to name a few. If you have a particular design you are interested in then get in touch and I can talk through the options, I am here to get you the best solution for your needs.

Still Confused?

No worries, we are happy to help you to ensure you get the bag you want and suits your needs. Just get in touch and we can work through it. 

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