Racks are ideal for carrying luggage on a bike. Lights are essential for cycling after dark. If you’re cycling for transport, you need both of these accessories. Yet many lights are designed to be attached to the bike’s seatpost, where they may be obscured by the stuff you put on the rack. The solution is to mount the light to the rack.
Some racks are designed with light fixing points welded on. These fixing points can take the form of a tab, a short tube or a small vertical plate. Tabs and tubes allow you to use the bracket supplied with the lamp. A vertical plate may require an additional plastic bracket (one that is compatible with the lamp).
However, many racks don’t have anywhere at all to attach a rear light.
Here’s a way of adding a fixing point to a rack that doesn’t have one. It works for racks with a top plate.
How to mount a light beneath a rack
This is how to add a short post beneath the rack to which you can attach a light. It’s a bodge that allows you to use the seatpost bracket supplied with the light, meaning you don’t need to buy another bracket from Cateye or whoever.
The central ‘component’ in the design is an empty thread spool. Spools come in two shapes, short and fat or long and thin. The fat ones are about the same diameter as a seatpost, so a seatpost bracket should be a close fit. Market stalls are the cheapest place to buy spools of thread and offer the widest choice; supermarkets are the most expensive. You don’t need the thread, just the spool.
- a plastic thread spool, with thread and labels removed
- a bolt, 15mm longer than the spool and narrow enough to fit through its centre. I used a roofing bolt because it has a domed head
- a nylock nut to fit the bolt
- a washer
- your LED light and its seatpost bracket
- a rubber strip to use as a shim (needed if spool and bracket are slightly different sizes). These sometimes come with the light. A strip of old innertube will work.
- a drill
- a drill bit slightly wider than the bolt
- a spanner to fit nylock nut
- a marker pen
- Fasten your light bracket to the spool. If necessary, shim it using the rubber strip.
- Mark a point on the centre of your rack’s top plate, a few centimetres from the rear edge. This will be the centre of the spool.
- Drill a hole in the top plate at the point you’ve marked.
- Slot the bolt through the hole and fasten the spool to the underside of the plate using the nut and washer. Line up the bracket and tighten the nut so the spool does not rotate.
- Attach your light.
A light mounted underneath a rack in this way is less likely to be bashed by panniers when the rack is being loaded up. It also gets some protection from the rain.