Igaro D2 Under Stem Mount/Case

Igaro D2 Under Stem Mount/Case

Original price was: R699.00.Current price is: R599.00. excl. VAT

In stock

Original price was: R699.00.Current price is: R599.00. excl. VAT

Discretely mounts the Igaro D2 under the bicycle stem. We occasionally 3D Print these. Search Igaro on thingiverse.com for more information.


The Igaro D2 is designed to work only with STVZO 3W dynamo hubs (all Shimano, SON and SP dynamo hub models are supported). 2.4W “LED” dynamo hubs provide less power and are less suited to USB charging. Using bottle or rim driven dynamos may damage the Igaro D2 and such usage is not covered under warranty.

Power Lead

Ensure the power lead is immobile by securing it (i.e cable tie) so that it moves with the main unit. This will prevent metal fatigue of the wire which could eventually lead to fracture. For example if the unit is situated on the handlebar then the power lead should move with the handlebar. A violation of this rule would be to place the unit on the handlebar and securing the power lead to the head tube.

USB-C Leads

Both USB Adapter Charging v1.2 (USB-A) and USB-C CC (Current Control) protocols are supported. Poor quality USB-C leads may only support the USB-A protocol and not work well if at all for USB-C to USB-C usage. Use original or good quality USB-C leads that specify USB-C CC (Current Control) or USB-C PD (Power Delivery) support. Keep leads short for slightly higher efficiency.

As with the power lead we recommend immobilizing USB-C leads to move with the main unit. Also note that all USB ports suffer electrolysis (corrosion of the pins) when wet. For a long working life it is vital water does not enter USB-C ports. This is discussed further in Placement.

For supporting multiple devices use USB-C leads with metal connectors. These are thinner then most plastic counterparts. Some plastic ones will work, as shown, but rubberised ones generally won’t fit. For breaking out to a USB-A port use an adapter on a lead and not the type shown.

Bicycle Lights

Dynamo lights can be wired in parallel directly to the dynamo hub. For Schmidt SON hubs piggyback spade connectors can be used. For Shimano and SP both wires can be twisted together and inserted into the plug that comes with the dynamo hub.

Dynamo hubs don’t have the capability to reliably power a dynamo light and USB device concurrently with a degree of reliability (they fight each other for power). For this reason we’ve chosen to automatically turn the Igaro D2 off if a dynamo light is detected3.

Dynamo light detection is performed on motion start. Dynamo lights should be in manual mode and you should come to a stop before turning them on otherwise it is likely the detection method won’t work.


Chose a location where the USB ports are protected from water ingression. While the Igaro D2 is water-proof, if water enters a powered USB port it will cause corrosion of the USB pins and lead to eventual failure1 (see FAQ). The Igaro D2 produces no heat and can be placed inside a bag however when doing so consider how other items inside the bag could move and apply force to USB leads and the sockets they connect to.

A handlebar mount is available that places the unit in an easy-to-access location and at an angle which naturally protects from water ingression with a rain skirt providing protection from driving rain. This is our recommended mounting solution.

We’ve also designed 3D printer models for positioning under the stem or to allow re-using an existing bicycle light bracket via a longer bolt. See thingiverse for details. Occasionally we print batches of these and add them to our online store however they are time/resource intensive and we frequently run out of stock. For customization you can download and edit the Freedcad (0.18) under stem or light bracket files.


Four lights (red and blue per USB port) provide status and diagnostic information. You should only attempt to look at them in a safe and controlled environment. Igaro is not responsible for loss of bicycle control or damage or injury caused due to attempting to inspect these lights whilst riding.

When the bicycle begins to move version information is displayed by a series of red flashes. The left red light denotes software version and the right red light denotes the selected dynamo hub model.

The system then waits for stable motion, which is approximately the same speed held for 4 seconds. After this, dynamo light detection is performed. If a light is detected the unit will alternative its red lights. For this reason always come to a complete stop when turning dynamo lights on or off.

The red light for either USB output indicates a minimum speed has not been reached. The default minimum speed is 8kph and will later vary based upon whether a USB device is successfully powered. For example if a USB device fails to power on at 8kph a percentage increase will apply and a further attempt will be made at the higher speed. If successful and then later speed decreases to 5kph and power fails the new speed will be 5kph plus a percentage increase. The speed value for each USB output is independent.

When either USB output is powered its red light will be replaced by a blue light. The blue light uses a pattern to indicate how much power the connected USB device is consuming.

With power successfully applied to USB output #1, and after a short period of steady motion, if there is minimal output (i.e the connected USB device is fully charged), and the minimum speed is met for USB output #2, then USB output #2 will enable. If USB output #1 later begins drawing significant power then USB output #2 will disable. As such, USB output #1 can be considered to have priority making it best suited for primary devices such as GPS and smartphones whereas USB output #2 is best suited for power-banks, camera chargers and rechargeable bike lights.

Power availability and output consumption are continuously assessed. If an imbalance is detected the system may restart a USB output (auto-reconnect) to further greater consumption. If unsuccessful it won’t occur again.

Blue light patterns

  • Quick flash – USBv1 (<= 100mA).
  • Equal flash – USBv2 (<= 500mA).
  • Mostly on – USBv3 (<= 900mA).
  • Steady on – USB-C CC (<= 1.5A).


The Igaro D2 has no internal storage and so power isn’t available when stationary. Constant monitoring ensures USB devices won’t experience unstable power fluctuation as the bicycle slows down. Some USB devices like smartphones may ‘wake-up’ when power is lost however newer phones (Android 9+) usually have a setting in the menu to disable this. See the general FAQ for details.

A common query is whether it’s best to charge a device direct or to charge a power-bank and then ‘dump’ the power later on. With the Igaro D2 lacking an internal power store it’s more important to choose the right approach for the USB devices you wish to charge. See the Compatibility page for further insight.

Always remember, there’s no such thing as a USB port that doesn’t corrode when wet and to keep water out for a long working life. If water has entered a USB port immediately stop riding and remove any connected USB lead. Shake the unit downwards to remove excess water then point upwards to allow remaining water to evaporate. Do not start cycling until you are sure the USB port is completely dry.


The Igaro D2 uses a programmable processor which uses software that we write. It’s well tested and we don’t expect to discover any bugs or to release new features, however we’ve left the door open for things we can’t plan for, specifically future dynamo lights which are found to be problematic with the Igaro D2’s detection method.

Software updates will always be free, however a custom programmer is required meaning the unit has to be returned to us.