TEST: Decathlon ST510 – the inexpensive front light with StVZO approval impresses with its uncomplicated installation and flexibility. We test the bicycle lights and show what they can do.
Test of the Decathlon ST510 – all information and data about the bike light at a glance
The Decathlon ST510 is a StVZO compliant bike light with built-in battery. It is available for €29,99, making it one of our affordable models Leaderboard. Accordingly, the material and its workmanship are of lower quality than the more expensive candidates in the test field. Nevertheless, there is no reason to complain here. The set also includes a rear light - so buyers are fully equipped. The handlebar mount with a sturdy elastic band is also practical: If you have several bikes in use, you can change the bike light back and forth quickly and easily. The light output is rather low at 25 lux, which is why Decathlon also specifies a driving speed of up to around 15 km/h. With IPX4, the bike light is only splash-proof - so users should not leave their bike standing in the constant rain with the lamp mounted.
data sheet
| luminosity | 25 lux |
| light modes | 2 (25lux – 15lux) |
| Lighting time | 2 h – 4 h |
| Charging time | about 2 h |
| charging connector | micro USB |
| Mounting options & adapters | Links |
| performance battery | 750 mAh |
| battery | No |
| Remote Control | No |
| weight with bracket | 62 g |
| StVZO approval | Ja |
| Color temperature | |
| Price | 29,99 € |
What's in the box
The Decathlon ST510 comes on a plastic-free cardboard display with the following scope of delivery:
- Decathlon ST510 bike light
- Handlebar clamp with rubber tension strap
- USB-A to Micro USB charging cable
- Rear light with holder for the seat tube
Accessories & Extension
Unfortunately, Decathlon does not offer any other accessories.
Test: The Decathlon ST510 in use
assembly and fastening
The handlebar mount of the Decathlon ST510 is attached to the handlebars using a wide, robust rubber band. Different eyelets for different handlebar diameters can be hung on a hook. The holder can be installed in a matter of seconds - the same also applies to the included rear light.
The lamp body itself is simply attached to the holder and clicks into place neatly. A small lever must be pressed to release it. All of this works well even with gloves - the Decathlon ST510 is suitable for winter. The handlebar mount sits firmly and securely on the handlebars - but you have to apply a little force during installation in order to attach the rubber strap tightly. Thanks to its low weight, the lamp itself practically does not wobble, even on forest paths.
Service
Operating the Decathlon ST510 is quite simple: a rubber button switches on the bike light, and pressing it again switches to the second brightness level. Pressing the button a third time switches the lamp off again. However, this has the disadvantage that you briefly drive in the dark when switching from the weak to the strong light level. This takes some getting used to and is not entirely safe - you should always keep it in mind. The button itself is not illuminated - this means that it is hardly noticeable in the dark. Accordingly, sometimes you are looking for something. This is less of a problem in twilight or street lighting, as the button stands out due to its gray color. You can't always feel the button straight away when you're wearing gloves. The fact that it is attached using a rubber band has a disadvantage when it comes to operation: When you press it firmly, the lamp wobbles quite a bit, but it didn't move during our test drives.
battery & runtime
Decathlon states the charging process for the ST510 is 2 hours. The charging socket itself is located under a tiny rubber cover, which is a bit fiddly to handle. The 750 mAh battery is charged via an outdated micro-USB port - USB-C would be much more modern here. With the maximum luminosity of 25 lux, the bicycle light has a running time of 2 hours. The second and weaker light level has 15 lux and a running time of 4 hours. On cold winter days, however, as with all battery-operated bicycle lights, you have to expect less. If the battery level is nearing its end, this is indicated by the button lighting up red.
The light field of the Decathlon ST510
The Decathlon ST510's light field is limited to the bare minimum, but that happens pretty well. The road is illuminated very evenly and the light beam is effectively focused. But that's it - shoulders and curves remain dark. At least the area directly in front of the front wheel receives some light from indirect radiation. The light is particularly suitable for cyclists who have few curves on their routes and who tend to travel in urban areas. In urban areas, streets are usually additionally illuminated by street lamps.
The 25 lux are quite dark compared to our brightest test candidates - but the ST510 only costs a fraction of that. For this reason, as mentioned, Decathlon specifies a speed of up to 15 km/h. Comfortable cyclists should be able to handle it well, especially in urban areas. The second light level with a little more than half the power is primarily limited to an illuminated environment. Or on steep, leisurely uphills in the dark. During our test drives, we didn't feel uncomfortable even at higher speeds.
The light levels in direct comparison
The following animation automatically shows the two different brightness levels of the Decathlon ST510.
