Service » FAQs


FAQ Hub Dynamos

There is a rattling noise on the hub dynamo, what to do?

If a hub dynamo causes a rattling noise, its axle is not clamped well in the fork. The reason may be sluggish threads that lack grease or wrongly fitted small parts. Please follow the instructions for the skewer or quick release or ask a specialist to show you how to mount the front wheel.

Should I grease the skewer?

A lot of grease on a 5-mm or 15-mm skewer may block the pressure compensation system. Nevertheless, to avoid corrosion, we recommend a slight film of oil or grease; best idea will be applying some spray wax. In any case contact areas at screw head and thread need some grease.

How can I protect my hub dynamo against corrosion?

For average use corrosion resistance of SON hub dynamo materials will be sufficient. Cyclists who cycle a lot throughout the year in all weathers and expose their hubs to salt water should apply spray wax to skewer and hub housing before each winter.

Do bearings on a SON hub dynamo need any maintenance?

SON Nabendynamo bearings are sealed on both sides; they are lifetime-lubricated grooved ball bearings. Normally they run maintenance-free for many 10 thousands of kilometers and need neither lubrication nor adjustment. Should a fault nevertheless occur the bearings will be replaced by the manufacturer.

How much play may the bearings have?

New grooved ball bearings have about zero play. During longterm-use the play may increase within a few hundreths of a millimeter. At the rim you may feel a small movement to the right and to the left then. Even when you continue cycling with a lot of bearing play no damage will occur.

Has my SON hub dynamo become sluggish?

It is hardly possible to feel power consumption/sluggishness of a hub dynamo at the axle. A better idea is to spin the normally fitted wheel and observe its stopping behaviour. When lights are switched off spin the wheel with some impetus. It should do a few revolutions. If it stops after one revolution something has gone wrong.

Why did the connection turn when riding the bike?

Either the skewer was not fitted correctly or the hub dynamo has become sluggish. Please check if the connections on the hub dynamo or the connections on the cable are damaged as soon as the axle is mounted well in the fork.

No Light Output

When neither headlight nor rear light shine, the reason is hardly a faulty hub dynamo but more likely the headlight or the wiring. Systematic troubleshooting will make sense.
You may check if there is power output on the hub dynamo by doing the short-circuit test: spin the wheel and short-circuit the spade contacts with a screw driver. The wheel will slow down. When interrupting the short-circuit you will see small sparks.

Do I need to respect polarity on a SON hub dynamo?

Like practically all hub dynamos the SON hub dynamo supplies alternating current. None of the poles (spade connections) has ground connection, so that you may interchange connections deliberately.

How much voltage and wattage does a SON hub dynamo supply?

Nominal values are 6 volts and 3 watts. They are achieved at moderate speeds depending on wheel size and generator type. The real values depend on the electrical load to a large extent indeed. Running with no electrical load results in remarkably higher voItage. At high speeds and with suitable electrical load you may use significantly more power.

Can you operate just a headlight with no rear light on a SON hub dynamo?

Nominal power of a dynamo-powered headlight normally is 2.4 watts, the dynamo is 3 watts. The remaining 0.6 watts are intended for use of a rear light. A high-end LED-headlight tolerates 3 watts easily, though, and will thereby shine brighter. With lightbulbs that was not possible.

Can I use 15 mm or 12 mm thru axle dynamos in standard 9mm QR forks?

Yes, with a suitable axle-adapter that is certainly possible. The fork will need to be of 100 mm width , of course.

Is the sense of rotation important on a SON hub dynamo?

All current SON hub dynamos do not have a defined sense of rotation. On a SON 28 klassik (year of manufacture until 2011) the connections must be on the right side, so that the threaded lid does not come loose.

FAQ Edelux

Can I power the Edelux II without a rear light connected?

Although nominal power on the Edelux II is 2.4 watts, it tolerates the complete electrical power supplied by a 3-watt hub dynamo. Powered with 3 watts light output is a bit higher.

Neither headlight nor rear light shine after connecting the rear light

A short circuit may occur due to a faulty rear light or a wrongly connected rear light. If the rear light has ground connection the conductors must not be interchanged: the Edelux ground connection (eyelet connector) must connect to the ground connection on the rear light.
The spade connector female at the Edelux must completely be covered with heat shrink tubing to avoid a short circuit with the Edelux housing.

Is an upside-down mounting position permitted with the Edelux II?

There is a special version for upside-down mount. A standard Edelux II fitted upside-down would have a very bad light distribution.

In senso-mode the light switches on quite early

The sensitivity of a light sensor is a matter of taste. For safety reasons we decided for high sensitivity, so the light may switch on in cloudy conditions. Due to the light sensor‘s mounting position showing diagonal downwards the sensitivity of the light sensor also depends on a possible wide and dark mudguard below.

Is it possible to run 2 Edelux II on one hub dynamo?

In contrast to headlights with bulbs, it doesn‘t make sense to run 2 Edelux II on a hub dynamo in general. You may connect 2 headlights in series, but only at very high speed there will be significantly more light.

May I use an Edelux II on a battery?

Edelux II for hub dynamo is not suitable for DC current. There are two versions for DC current, though (6 to 8 Volts and 6 to 75 Volts). Those must not be powered by AC current on a hub dynamo.

Can the Edelux II LED be replaced?

No, the LED is always firmly fitted into a bike headlight and will last forever, given that it is adequately cooled. Changing to a more modern LED-Type is normally not possible for another reason – the different radiation angle will requires a different mirror.

Is there any Edelux with internal USB charger?

No, SON currently offers neither internal USB chargers nor external ones. But we provide several products, that split cables and thus help to connect charging devices easily (see also wiring).

FAQ Rear Light

Can you use a SON Rear Light on a Pedelec?

Yes, you can power a SON Rear Light on a Pedelec 25 with regulated 6 Volt output or on the rear light connection of an Edelux II DC 6 to 75 Volt.

Can you connect a SON Rear Light to a Supernova headlight?

Yes. Conversely you won‘t have standlight with a Supernova rear light connected to an Edelux.

Is a SON Rear Light mounted vertically permitted?

No. The SON Rear Light has very wide but not very high beam angles. When mounted vertically this would be vice versa resulting in poor visibility from diagonal back.

FAQ Charging

Can you run mobiles, smartphones and navigation devices on a hub dynamo?

Yes, you can. You will need a charging device that regulates the alternating current from your dynamo to constant direct current. We recommend "USB-Werk" from Busch&Müller for USB-devices that work with little power consumption.
Modern smartphones with permanently switched on displays consume 2-4 watts. Not many charging devices are efficient enough to work well with those. Highly effective at any speed are „Forumslader V5“ and „NC-17 AppCon GT1“.
CAUTION: permanently connected USB-cables may damage the charging socket of your phone on bumpy roads. When a cable is connected your device is not waterproof any more. Take care not to get distracted from traffic by your smartphone or GPS device.

Can you charge a device with lights switched on at the same time?

Most charging devices do not charge if the headlight shines at the same time; some of them might work with a small fraction of their nominal power. It makes sense to switch the light off when powering a USB-charger. You may connect an Edelux II DC 6-75V and a navigation device to the 12 V output on a „Forumslader V5“. If the buffer battery of the Forumslader V5 is well-charged you can power the light and your device at the same time.

What loading current can I expect from a hub dynamo for my mobile device?

Most simple charging devices supply no more than 400 to 500mA at their USB-output. Modern devices, such as USB-Werk may supply 800mA (which corresponds to 4 watts). Even when using efficient charging devices you will need to go significantly faster than 20 km/h to achieve such high power output.

Do I need a buffer battery when charging my mobile?

Smartphones like those from Samsung or Apple require constantly high charging power. This will be difficult to achieve without a buffer battery. On your leisure GPS device warning messages may appear as soon as you stop at traffic lights due to lacking power supply. A buffer battery will help.

What is the difference between SON 28 and SONdelux regarding charging properties?

Classic mobile phones and GPS devices work with economic power consumption. You can power them with a suitable charging device and a SON 28 or a SONdelux just as well. If you would like to charge a power-hungry smartphone at speeds lower than 20 km/h you should rather go for a SON 28. At speeds higher than 20 km/h you may charge a modern smartphone by using a SONdelux together with an efficient charging device.

How does a charging device connect to a SON hub dynamo in addition to a headlight?

Connect charging devices to a hub dynamo in parallel with the headlight, n o t at the rear light output of a headlight. We recommend to crimp 4.8 mm piggy-back connectors to the feedcable of a charging device. The headlight cable connects to the tongues on the piggy backs. If you connect and disconnect the charging device frequently our Coaxial Junction Box will be a good choice.