FAQ – Team Zwatt

Good question. We get that a lot. But the real question may be: Why not?

You want to help us evolve the technology to the point where all your bikes can have a power meter without breaking the bank. So you want us to have an incentive to keep providing progress on that.

And we want you to keep providing real world ride data for our test database. So we want you to have an incentive to keep doing that.

So why not a monthly fee that we can discount when you upload data to us?

We also want you to have the lowest possible initial investment to start generating data for us. By splitting the price like that, we can offer you the lowest possible price to get started.

For the ZPIDER, please go through the guide to fit and accessories. Or ask a skilled mechanic if in doubt.
For the ZIMANOX it’s even better 🙂 If you don’t have a road bike Shimano crank already, you just sell whatever crank you have. Then you put a Shimano crankset on and the ZIMANOX will fit unless you have clearance issues. Please see that question also.
If you don’t think this is perfect for any of your bikes, be patient. We will have other options coming later – including MTB.

ZPIDER is based on FSA’s Gossamer crankset with a BB386EVO spindle format. This fits most bikes. You can read more in the support guide to picking the right accessories. At this guide, please read also the link to the guide to BB386EVO compatibility

If you have a wide frame with press-fit bearing, please be careful. The ZPIDER gen 1 will not fit all wide press-fit frames.

It depends on what style of frame and bottom bracket you are using. For proper installation please follow the ZPIDER first time install guide.

For ZIMANOX this is because ZIMANOX only measures your left side.

For ZPIDER this is a minor bug in that we measure only one number for pedal smoothness (i.e. average for both legs), but when sending to bike computer etc. via the ANT+ protocol, the data fields are a number for left and one for right. As we have only one number, we send this to the left field only, which confuses users. It’s on the list of things to improve.

Maybe. If your crankset is a Shimano road crankset: Yes. If you strongly prefer some other crankset, you either have to be (potentially very) patient or go buy some other (probably pedal or rear hub based) power meter.

No. It is integrated with the FSA Gossamer crankset. You will get a complete crankset, and simply just install chain rings in your preferred size.

If you have a set of Shimano style 4-arm 110mm BCD (introduced in 2013) you can fit them to the ZPIDER.  You can also find a set of chain rings in your preferred size for the ZPIDER in our webshop and have that shipped with your ZPIDER.

No. Bolts are included at ordering chain rings (they are specific for different chain rings).

Yes. FSA Cranks are compatible with all of the above.

Yes. We have the 3 most popular lengths now: 170/172.5/175mm. 

No, the ZIMANOX design is created with the help of STRONGLIGHT in France. They have verified the strength on a fatigue tester to the ISO standards. And we have verified the stiffness to be comparable to an Ultegra arm.

You should make sure that the ZIMANOX will not interfere with the chain stays of your frame.

Take a look at the figure below. Get your ruler, and check that there is sufficient space on your frame. Note that all the dimensions in the figure are i mm. 

Yes, it will automatic compensate for temperature changes.

Calibration is done to set the zero offset of the highly sensitive torque measurement pretty much like the tare function on a kitchen scale.

There is no need to calibrate the power meter for every ride. Calibration is recommended after any mechanical changes to the crank such as changing pedals, chain rings, installation of the crank, tightening of bolts etc.

We will not add the auto-calibrate feature to ZIMANOX, but may do that on the ZPIDER.

We’ve identified a bug in firmware version 1.18. We’ve fixed it and added tests to ensure it won’t happen again. The new firmware is released as version 1.21.

Main releases and beta release

Before offcially releasing firmware we put it through a set of tests to ensure we fix bugs instead of creating them. However, since we’ve got the largest test team in the world it makes perfect sense to make the firmware available to them too. We do that in the form of beta releases.

You can distingues a main release from a beta by the first number. Zero dot something is a beta, one dot somthing is a main.

Please send us data, preferably a .fit file together with raw data from your app. Only with data are we able to analyse this kind of issue and give recommendations.

Make sure you perform a calibration from the head unit or app before the ride. First thing we check is if your zero is good at the start. Never have any force at all on the pedals when doing the calibration.

We have seen some Android related Bluetooth issues. Turn your bluetooth off and on again. That will do the trick in most cases.

The power meter is specified for -10°C to +50°C but will probably work at -20°C as well.

This is where you come in – we will love it, when you test it out for us.

Using Shimano? Yes. Else: No. The first models released will be factory installed to the specific bike parts.

The ZIMANOX model will show power calculated based on left leg power.

The ZPIDER model will provide dual leg power measurements and left/right balance.

Yes, mechanically the Power meter is 100% compatible for use with non-round chain rings, but any sort of oval or non-round chainring will affect power measurement. It is not a sign of poor quality or design of the power meters, but rather a question of simple physical character.

Our power equation assumes a constant velocity. The power meters assumes a constant speed throughout each complete revolution. With oval chainrings, the crank velocity will change during each pedal stroke, so you spend more or less time in certain parts of that pedal stroke. The net effect is that you’ll get slightly inflated power numbers using an oval ring. It can range from a few percent and can be as much as 5% increase, and depends on how odd-shaped your ring is.

We have better support for oval chain rings (O.Symetric, Absolute Black etc.) on the list of improvements we plan to do and release as a firmware update. Till that happens, you can use the function in the app under Settings > Power Measurement Trimming to slightly adjust the power reading from the power meter. Enter 2 to increase the power output reading by 2%.

When you have created an account here on our website, go to settings in the app and type in your account info. Activate the power meter by turning the crank arm a few times and start the app on your phone (or if the app is already running, make sure you’re in the dashboard view).

iOS Dashboard


Leave the app in dashboard view and when it finds the sensor, it will ask you if you want to assign your account to this power meter. Be aware that will work only when you start the app. If the app was already running in the background, this will not work.

This is done once, and you’ll not need to do it again.

Settings view


When the account and the power meter are linked, the power meter will automatically know when the maintenance fee is paid and keep your power meter running.

Note also that when your app has been assigned an account, you can see the account name in the bottom of the settings screen.

The app is logging data when it is connected to your power meter during a ride. You cannot actually see that data is being recorded, but to make sure that data is being recorded do the following:

  • In Settings, ensure that Logging Enable is enabled
  • Once you would like to upload data to us, press the Upload data to cloud now

If there is no data to upload, the app will warn you.

Basically by using the app. Connect the app to your power meter before you start a ride and data is collected automatically.

You can then upload data after each ride or just do it from time to time, e.g. once a week or once per month.

Be aware that if you prefer riding using your bike computer, you can do so at the same time. Our app just need to be open and active during the ride, but you can have your phone in your pocket or wherefter you prefer.

Yes, data is transmitted through BLE and ANT+ on all our devices, so you can use them with either our own or a third-party mobile app, and your bike computer simultaneously (BLE is often referred to as Bluetooth Low Energy, Bluetooth 4.0 or Bluetooth Smart).

We basically ask for two types of data:

  • Background data and opinions through quick and simple surveys.
  • If you are in one of the power meter groups, we ask you to share the raw GPS and PM data of at least one ride per month.

The easiest way to share your ride data with us is by using our mobile app to track it and upload it to our servers.

The primary goal is to use diverse data to optimize the software algorithms. Different biking styles and surfaces matter a lot in estimating cadence and thus power. As an example: for MTB we have been chasing the dreaded power spikes from vibrations that many power meters seem to have issues with (experiencing power spikes means you can’t trust your max value, and you start to question other data). We think we have that pretty much under control and are outperforming other power meters output as we can see it on Strava – but having more diverse data would definitely help us improving this further. Constant improvement is the name of the game and our Team ZWATT members will make their own power meter better.

No. The data we need can only be recorded through the App as it contains way more information than you can collect with a standard head unit.

Yes. Come on – we are from Denmark. What do you think? We test to IP67 level (look that up on Wikipedia if you need).

It is displayed in our app, may be seen in third party apps that follow the standard protocol and most head units/bike computers.

If the green light in the charging pod comes on, your USB charger is connected and on. Good.

If  the red light does not go on when you connect the charger pod to the power meter that is unusual. If the two contact points does make contact the red light should go on. If not, here are a few things to try:

  • Try wiggling the charger around a bit and see if you can get the red light to turn on
  • Check the two contact points on the charger are “sticking out” (spring loaded contact points – so called pogo-pins). Could they be stuck somehow?
  • Are the contact points on the ZPIDER clean? (we have seen one case of a thin layer of glue on the contact point)

Yes, the power meter technology we use is 100% direct measurement meaning they use strain gauges.

The measurements offered are: power, cadence, torque effectiveness (ZIMANOX only) and pedal smoothness.

Yes. A crank based power meter needs to measure cadence in order to calculate the power.

Not at all. If you would consider buying a power meter, you are exactly the type of rider we are looking for. We want the products to be tested by the same types of riders that may later buy them.

During the development process we learned a few important lessons:

  • Testing by pro riders may be extreme in power and intensity, but it’s not as diverse as the riders actually buying the products
  • The difference between power meter algorithms surface when they are put in real life situations

That is why the results generated by the pro riders testing our technology for the brands, is not nearly good enough for us, and we decided to establish Team ZWATT to change this by crowd sourcing the data collection to help take power meter technology to the next level.

  • Better algorithms
  • Better price
  • Better products that works better for your style of riding

These power meter models are being built specifically for Team ZWATT to gather data on the different models and to fit a wide variety of users and bikes.

Being part of Team ZWATT is free. The power meters we are providing for testers are not free. We strive to make them as inexpensive as we can. Our vision is that you should be able to afford  a power meter on all your bikes.

You can find the actual prices in the webshop.

There is a fixed price to get the physical product and a monthly maintenance fee to keep it running (after 2 years, the fee goes to zero).

No. We are a startup and not making the kind of money required to do that. Creating Team ZWATT is also a reaction to the idea that you can sponsor equipment for a few riders and get valuable testing -and- promotion in return. Sponsoring is actually not a very good way to get unbiased test results.

Well simply put:

  • We present the power meter models we want you to pre-order. There are different “pledge” options with different prices and limits on quantity. The cheapest tend to go first 🙂
  • You pick what you want and “pledge” that (i.e. pay with your credit card)
  • At the end of the campaign (Sep 1st). If we hit the minimum amount we set, Kickstarter will charge your card and pay us the money.
  • We complete the various bits missing, manufacture the units and ship them to you.

To learn all about Kickstarter read the Kickstarter FAQ.

We have released arm and spider based power meter solutions (we call them ZIMANOX and ZPIDER). These bike parts will come with a power meter module integrated in them. All you have to do to install them is to swap your old bike part with the new.

Not one style fits all and that’s okay. We will have more versions coming. Get on the team and we will keep you updated.

In the August 2016 Kickstarter Campaign, the ZIMANOX and ZPIDER versions were offered with a ZPINDLE MTB as a stretch goal. The September Indiegogo “top-up” Campaign had the ZIMANOX and ZPIDER available also.

Team ZWATT is run by SENSITIVUS gauge – a Copenhagen based danish start-up developing advanced electronics for bike brands. The first products include power meter sensors for crank based power meters. Here is a short video pitch we made for our office park (Watch on Youtube).

If we get bought up? We drink champagne. Easy 🙂

No seriously, we have thought of that situation a lot. Since the power meter will default to stop working after a while unless you connect with your smartphone and give it more life. This requires that we are still there to run the servers.

If we get bought up – the buyer will also buy the obligation to continue the service. No problem.

If we close – we will simply unlock all the power meters.

And to make that 100% sure, Rolf Ostergaard (CEO and majority shareholder of the company) has issued a standing order to the lead software developer to unlock all power meters right away if the company looses its ability to make decisions for any reason.

Have another question?

Please email support to get your question answered by a human if you can’t find the answer you need on this page.

Make sure to include app and firmware version numbers, if at all relevant to your question.