Douze FAQs

Maker: Douze Cycles in France.

Bike Operations

What are the specs of the bike?

  • Rear Frame: Steel CrMo 4130
  • Front Frame: Aluminium 7005 T6
  • Color: Matt black / Glossy white – Powder coated
  • Fork: Steel CrMo 4130 – QR 9 mm Axle
  • Kickstand: Steel CrMo 4130
  • Rear Hubs: 135 mm – 36H – 10 mm Axle – Black
  • Front Hubs: 100 mm – 36H – QR 9 mm Axle – Black
  • Rims: 20″+ 26″- 36H – Alu Dble side – Eyelets
  • Tires: SCHWALBE Big Apple 26”+20”x2.0”
  • Brakes: TEKTRO Gemini Hydraulic – Disk 160 mm
  • Fenders: Stainless 60 mm- Powder coated
  • Steering System: Steering by 2X2 cable + KEVLAR housing
  • Steering Column: Adjustable – Easy-up
  • R/F Headset: 1″ 1/8 Semi-integrated
  • Handlebar: Moustache – 640mm
  • Stem: 60mm – D1: 28.6 – D2: 31.8
  • Seatpost: D 31.6 – Adjustable 2 parts (H82-110c)
  • Pedals: City- VP 856 – anti-skid
  • Front/Rear Mount: 2 X Anti-theft axles
  • Gears: SRAM Ext Der. XSerie 9V or NUVINCI N380 – 19t
  • Crankset: First DT1 38t or CNC 34t – 44t (Motor Reduc : 1.3)
  • Gear Ratios: S1: 2.43 m – S9: 7.08 m or Low: 2.25 m – High : 8.57 m
  • Bottom Bracket: Internal 68 mm – 1.37”x24t or Internal 68 mm – 1.37”x24t
  • Chain: TAYA Octo DH 1/2”x5/64”
  • Light: LED Light F/R USB rechargeable
  • Wood Board: Anti-skid plywood board
  • Side Tube: Aluminum – Powder coated

All parts and components subject to change, based on availability.

How does the electric assist compare with other electric assist systems? What about the brakes?

See the electric assist specs here.

How old should my kid be before sitting in the main seat? When do I know when my child is too big?

Kids can sit in the main seat as soon as they can sit upright on their own and fit into a helmet. For small children whose feet don’t reach the ground, put a bag under their feet to add more stability. Babies who cannot yet sit up and wear a helmet should ride in an infant seat. If your passenger’s head or body interferes with the steering of the bike, is below 18 and can’t be secured in the seat by the harness or exceeds the weight limit of the cargo box, the passenger is too big to ride.

How do I use the kickstand?

Press your foot on the bar running along the bottom back of the front box (under the handlebars) while pulling the handlebars back. You may need to use more force than you expect the first time you try this. To disengage the kickstand, just use the handlebars to rock the bike forward.

How do I shift gears?

Derailleur: Use the levers to shift up and down. It’s always advisable to take a bit of pressure off the pedals as you shift.

Nuvinci: Twist the grip on the right side up and down. Twisting up makes the bike easier to ride. Twisting down makes it harder. You can twist to change the gearing whether you’re pedaling or stopped. If you’re twisting while pedaling, take pressure off the pedals while you twist. While the bike will shift under load, it is not good for the system and may overload the mechanics.

What is the weight of the bike?

Depending on options and accessories added, the complete bike weighs around 53 pounds.

How much weight does the bike take?

200 kg, which is about 440 lbs. This weight limit includes the rider.

How do I avoid getting blown around when it’s windy and I’m using the rain canopy?

When the rain cover flaps are up, the wind can catch the sides of the cover and blow you around more than comfortable. Zip the flaps all the way down on both sides and secure the velcro to avoid catching the wind.

Electric Assist

How do I adjust the settings on my console?

To come.

How do you turn the electric assist system on and off?

To come.

Do I need to turn the electric assist system off?

To come.

The electric assist cut out while I was riding. What happened?


To come.

Does the BionX system have a regeneration mode? Does the E-Rad

BionX, yes. E-Rad, no.

Can I adjust how strong/weak the power is on the electric assist?

To come.

How do I take out the battery? Put it back in?

To come.


How do I turn on the lights?

To come.

The light isn’t working. What should I do?

To come.

Carrying Other Bikes

Can I tow a bike? How do I do it?

If you have a rack and well-installed pannier, you may be able to tow a small child’s bike. Place the wheel in the rear bag and use the bag straps to secure the wheel through the spokes and/or frame of the towed bike. We recommend also securing the frame to the bike with an additional strap.

Can I attach a trail-a-bike?

This is not a plug and play option. However, you may be able to find a professional machinist who will weld a trail-a-bike to the back rack. This solution only works for trail-a-bikes that attach to the back rack (not the seatpost).

Can I attach a trailer?

We don’t advise hooking up axle trailers to the Nuvinci hubs.


Where’s the safest place to lock the bike?

In a well-lit location where there are lots of responsible eyes on the bike. So, in front of a busy all-day cafe is more likely to be safe than a deserted alley. If you’re in San Francisco, check out the bike theft heat map for hot spots to avoid.


How do I adjust the position of my seat to be more comfortable?

You can make adjustments with the saddle attached to your bike or if easier for you, you can remove the saddle to make adjustments. Unlock your seat lock and undo the quick release. Then lift your seat straight up until it comes out of the frame. Turn the seat over and notice the large bolt right in the middle. Use a 5 mm Allen Key to loosen the bolt on the underside of the saddle. Once it’s loose, you can slide the seat forwards or backwards along the rail (just never go past the marked limits). You can also rotate the clamp, and click the seat up and down, to adjust the angle of the saddle. Once you have the seat where you want it, hold it firmly in place and tighten the bolt again and place it back in the frame.

The front stem is also adjustable. Try playing with its height to see how it impacts your comfort.


How do I position my bell to make it easier for me to ring it while riding normally?

You can use a Phillips-head screwdriver to loosen the bell so you can rotate or move it appropriately. Whether on the right side or left, you may need to rotate the bell to get the desired ring lever position that you prefer. Tighten the screw after you find the best position for you.

If you have smaller hands and/or simply feel you are reaching for the bell, we suggest upgrading to Incredibell brand bell (or other bell with longer ring lever) which will allow you not only to rotate the bell around the handlebar, but rotate the lever around the bell allowing you to bring it closer to the grips, making easier to reach. Incredibell fits nicely on the left side, allowing you to conveniently position the lever just over the console.

Yepp Seat

How do I take the Yepp seat on and off the bike?

Check out this helpful, brief video from Yepp.

Can the bike fit a front Yepp Mini or Bobike Mini seat?

We don’t advise this setup on the Douze’s adjustable tube.


I hear a scraping sound when I brake. Is that normal?

Yes and no. Disc brakes are essentially metal/resin pads that come into contact with a metal rotor. The friction of these two materials can create sounds. In particular you may hear some sound when braking at low speeds. While some noise can be expected and normal, contaminates or damaged pads can impact your brakes and lead to more concerning sounds. Note, even simple oils from your fingers can contaminate the system. Never touch rotors with your hands, especially after riding the bike, the heat build up from braking makes the rotors extremely hot. These contaminants, dirt and oil can build up over time on the rotors and pads during normal use. These need to be removed as part of regular maintenance. If your bike is making sounds it may be time to clean your brakes system and inspect pads for damage and or excessive wear.

How do I know if my brakes are in good shape?

The best way to know if your brakes are in good shape is to remove the pads and inspect them for damage and or excessive wear. If you do not know how to do this, you can schedule a maintenance appointment with Vie. Want to try it on your own? See below.

My brakes are squealing. Should I be worried?

Yes. While squealing brakes are most commonly an effect of contaminated pads and/or rotor it can also be caused by misaligned rotor, loose bolts or damaged pads. Squealing brakes should be addressed as soon as possible. You can schedule a maintenance appointment.

What can I do at home to keep my brakes in good shape?

With some basic tools and mechanical knowledge you can maintain your brakes at home. This is a good practice that will keep your bike and braking system operating safely. If not confident of your skill set, please schedule a maintenance appointment with Vie or email Karl with your questions.

Keeping your pads and rotors clean and regularly inspecting pads for damage and/or excessive wear is important and can be done at home. The following is a simple overview of the process.

  1. Remove the wheel. While the wheel is off you should take the opportunity to check torq on rotor bolts and clean the brake caliper.
  2. Remove pads and inspect them for damage and/or wear. You can clean your pads and rotors with denatured alcohol or various products which are sold at bike shops for this purpose. Install clean and or new pads if needed. Clean your rotor and inspect for damage.
  3. Re-install your wheel. Be sure to properly seat the wheel so the rotor is aligned and take caution not to damage pads when installing the wheel. Properly tension the quick release and check for rotor alignment by spinning the wheel. If installed properly you should not have any sounds and pads should be no more than 1 mm from the rotor. At this time, check the brake line for any damage and check for proper function of lever. Pads should come into contact with rotor simultaneously. Note, if new pads were installed you will need to complete a bed-in process.

My console is giving an error code. What does it mean?

To come.

What do I need to know to pump up my tires? How often should I pump?

You should check for the recommended air pressure called PSI (Pound Per Square Inch) on the sidewall of the tire. You must keep the air pressure within this range. It is recommended to check air pressure regularly (at least once a week). Note, while there is conventional wisdom that says lower air pressure is a softer ride; riding cargo bikes with heavy loads on low air pressure can lead to pinch flats.

I have a flat tire. How do I fix it myself?

With a tire lever, tube/patch kit and a little elbow grease, anything is possible! Or at least you can change a tube and fix a flat tire. Start by assessing how you will stabilize the bike while taking the wheel off and how the bike will balance with no wheel. Pending which wheel, and your kickstand style, you may need to turn it upside down; or simply put it in a bike stand at home. As for the repair itself, the key is to know what caused the flat. So take time to assess this and follow logical steps before removing tube and placing in new tube which may simply go flat in a few blocks.

After removing the wheel, inspect the tire for what caused the flat. Nail? Glass? Etc. Make note of it but don’t remove it yet, you don’t want to assume it’s the only issue. Remove one side of tire using a tire iron (we highly recommend Pedro tire levers, they’re yellow/pink/orange levers sold at most stores.) No need to remove whole tire. Pull the tube from the tire but do not remove the valve from the rim yet. Inspect the tube for where the leak is. You may know where based on the nail, glass you found earlier. If not, you may need to pump air into the tire and listen and/or feel for air leak. When you find the leak, line the tube back up to the tire and re-inspect the tire on the inside and outside to ensure the object is removed. If the leak is on the inside of the tube (facing the rim), you most likely were riding on a wheel with too low of air pressure. Either way, inspect the rim to see if something is there that caused the flat.

At this time remove the tube and take a new tube out. Get ready to install the new tube by filling  the new tube with just enough air to give it shape and swiping the inside of the tire with your fingers to ensure there is no additional glass, little wires, or other things that could damage a new tube. Now you’re ready to install the tube.

To install a new tube, place the rim in front of you with the valve opening at the top. Pull the tire back and insert the valve into the rim and fill the tire with the tube. Use your hands to position the tube well inside of the tire and rim moving all the way around the tire methodically. Now pull on the valve firmly and ensure it is perpendicular to the rim. Start installing the tire onto the rim with your hands. Follow the bead around the rim and try to seat the tire on the rim with just your hands if possible. If necessary to use the tire lever, be careful not to pinch the tube and cause another flat (this is why we give the tube shape with a little air and take the time to stuff it all the way into the tire and over the rim.) Once tire is on, inflate to proper PSI.

How often should I oil my chain? How do I do it?

It all depends on how often and in what conditions you ride. A good rule of thumb is that you should check your chain as often as you check air pressure. To check your chain all you need to do it pinch it. How did it feel? The chain should be slightly tacky. Not too dry. Not too oily. It should be its original color (gray, silver or brown). It should not be black with grime or rusty and dry for that matter. Pending how often you ride and in what conditions you may only need to oil the chain every couple months. If you ride often in wet and/or dirty conditions this may be much more frequent.

To oil use a clean rag and an oil designed for bike chains. There are endless options. Tri Flow is a popular choice. To start you want to apply oil to a clean chain. If necessary clean chain with a degreaser first and then dry the chain. When ready to apply oil think minimal. Apply a drop of oil to each link of the chain. After applying the oil, pedal the bike (while in place) to allow the links to move around the cassette which encourages the oil into the links. After 20 or 40 seconds of pedaling you can stop. Final step is to wipe all the excess oil from the chain with a rag. Be certain to also wipe excess oil off the bike and or components.    

My kickstand feels loose. How do I tighten it?

We highly recommend that if you hear or suspect that something is loose on the bottom of your bike, stop riding and contact Vie to either schedule a maintenance appointment or get advice on next steps. If you feel mechanically inclined you can check the kickstand fasteners and engagement rod.

The door is coming loose. What should I do?

You can adjust the door with the four bolts located at the hinge. Two fasteners hold the alignment of the door while two more fasteners attach the door to the frame. The Allen or hex bolts are located under plastic faceplates. Use a small flathead screwdriver or blade to remove the faceplate. You’ll need a 4 mm Allen key and an 8 mm socket to make adjustments to the fasteners.  

How worried should I be about bumpy pavement? Will riding on bumps mess up my bike?

While bumps in life are most likely unavoidable, we do want to avoid them when possible. The constant jarring of urban riding is tough on bikes, little ones and us. The constant jarring impacts wheels as well as general fasteners. Is it bad? Yes. Is it always avoidable? No. The most important thing is to ride safely when navigating rough roads and check your bike often to ensure all is well.

The Nuvinci system won’t work when I’m stopped/moving? What should I do?

The Nuvinci shifter will rotate or shift through about 60% of the available gearing. There are several reasons why you may not be able to turn the shifter or that the shifter is rotating freely. We suggest scheduling a maintenance appointment.

If you feel mechanically inclined and would like to assess the problem further, you can begin by removing the chain guard and inspecting the cables at the hub interface. Both high and low gearing cable should be installed correctly (see NuVinci Technical Manual) and the spring latch snapped to ensure it is seated properly. With cables installed the slack should be checked by pulling lightly on the housing where it enters the shifter. There should be between .5 mm and 1.5 mm of slack. If the cables are installed properly but the shifter is not rotating as expected, there is most likely damage to the housing and cables that is leading to friction or perhaps the shifter/hub itself has been damaged. Either way, further use could only damage it more. Avoid riding the bike further and schedule a maintenance appointment.