We’ll soon be offering a cycling accessory for carrying a D-lock (or U-lock) on top of a pannier rack. The rack strap makes it easier to lock up a bike. It serves as a universal D-lock bracket for those with a standard width pannier rack (or beam rack), since it is designed to work with any D-lock.

The rack strap will be useful to:

  • commuter cyclists who carry their lock in a pannier or a shoulder bag such as a messenger bag
  • touring cyclists whose frame is already full with bottle carriers and other accessories
  • those who need to carry more than one D-lock

It will allow easy D-lock carrying on any bike fitted with a pannier rack or beam rack (seatpost rack), including those which don’t accept frame brackets, such as:

  • bikes with carbon fibre tubing
  • bikes with triangular-section hydro-formed aluminium tubing
  • certain folding bikes or demountables, i.e. those that do not rest on their rack when folded, such as Dahon, Birdy, Moulton

This page has information about the design of this rack strap, the panniers it has been tested with, and the Twitter account to follow for news and availability updates.

Why it needs to be easier to lock up a bike

Imagine yourself arriving for work. You’ve run the gauntlet of rush hour traffic. You’ve arrived. All you need to do now is lock the bike.

Your D-lock lock is in your pannier. You packed it before you set off, so it’s definitely in there. Along with your laptop, and your lunch. And your waterproofs, and your pump, and your puncture kit. But it’s okay, you put it at the top.

It’s not there. “No problem,” you tell yourself, “I must have put it in the other pannier.”

But you can’t find it in there either. So you start unpacking your bags. And, since you’re at a bike parking stand, there’s nowhere to put the stuff, so it has to go onto the ground. Your laptop. Your lunch. And so you find yourself surroundings by your possessions, peering into a bag with a black interior, looking for a black lock.

Aha! There it is, right at the bottom.” Somehow, it’s tangled itself up in the sleeves of your waterproof. You knew you’d packed it. All you need to do now is put everything back in the bag, and then lock your bike. Everything’s okay. Except that now you’re late.

Your morning needn’t be this difficult

This is what can happen. It happens to me. It happens to lots of people. It shouldn’t be this difficult to lock up a bike, and it wouldn’t be, if there was a better way of carrying a D-lock on a pannier rack.



In design

I figured that a rack strap for a D-lock needed the following properties:

  • to grip the rack tightly
  • to hold the lock securely in place
  • to stop the lock shackle rattling against the rack tubing
  • to allow quick retrieval of the lock, even when I was wearing gloves
  • to be compatible with panniers, rack packs and seatpost-mounted bike lights
  • to stay attached to the rack when the lock was in use
  • to work with various designs of rack

I played with rack strap designs on and off for six months, improving effectiveness or usability each version I made. The breakthrough came when I combined polypropylene with rubber to make a fixed length fabric with a high-friction surface that would grip the lock under relatively low tension. This made it possible to use side release buckles as fasteners, which are quick to open and allow adjustment of the strap length to accommodate different D-locks. I chose a buckle that closes smoothly, with an audible click on engagement, and with a ridge on each half to allow ‘two finger’ closing.

First Impressions

The rack strap works better than I imagined. Once it’s set up, it doesn’t need adjusting, as the buckles stay in position on the high-friction surface. Taking the D-lock off the rack is quick: press the buckle tabs and lift the lock away. The strap ends itself stays in position, rather than springing outwards or flopping down, because the material has ‘substance’ thanks to the rubber backing. To secure the lock to the rack, you simply place it in position, squeeze the buckles closed and listen for the click. It’s a pleasure to use, but, more importantly, it has simplified my parking routine. When I pull up at a parking stand, I unclip the lock, unhook the farside pannier, lock the bike, then unhook the nearside pannier. The ‘unknown element’ of retrieving the lock from a bag is gone. This rack strap has proven to be a far better way of carrying a D-lock. There’s the added advantage that I’m less likely to leave the thing at home (something I’ve done once or twice), because now I can see if I have it with me.


In testing

I now need to know if it will work well for everyone who tries it – on their bikes, with their racks and their panniers – so I’ve given it to cycle commuters, asking them to test it. The following panniers are being used, to check compatibility. These bags all have different attachment mechanisms.

  • Ortlieb back roller – city
  • Carradice Carradura
  • Lidl shopping pannier
  • Altura laptop pannier

Some testers are using racks with solid tops, while others are using the traditional open-top rack without a top plate.

Initial feedback

I’m looking forward to the testers’ reports, but I’m encouraged by initial feedback. After fitting the rack strap and experimenting with it, one tester said, “this makes it really easy to carry the lock.” Another just said, “what a fab gadget.”

Coming soon

The first rack straps will go on sale soon. The release date will be announced, along with further updates, at @baileycycling.