Detailed view of the Gravaa system mounted on a bicycle's rear wheel.

FAQ

Our FAQ page exists to answer commonly asked questions about Gravaa and topics related to ordering from our site. If you scan through the list and don’t find the answer you’re looking for or do but would like some more detail, please don’t hesitate to contact us. We’ll keep this page updated with new questions as they come in.

General

What will I receive when I order a Gravaa wheelset?

When ordering a Gravaa wheelset, you will receive a front wheel and a rear wheel, plus:

  • Disc brake rotors of your choice (mounted in the selected size, 140-160-180mm)
  • A freehub body of your choice (pre-installed)
  • An ergonomically designed wireless control unit that mounts on your handlebar
  • A set of small tools and some necessary spare parts

How long is Gravaa’s expected product lifetime?

Gravaa wheelsets have a product lifetime comparable to standard wheels. We provide you with a 2-year warranty period on non-wear parts. If you experience any degradation or issues with the performance of your wheels, please contact us. We will make sure to get you back on the bike as soon as possible. Read more about warranty conditions here.

Can I ride without a control unit?

Yes, you can. With the Gravaa app installed, your smartphone is an alternative control and display for riding. Without your phone and control unit, you cannot adapt the pressure of your tires. In this instance, Gravaa will maintain the pressure of your last used setpoint.

Do I need to pair my wheels and/or control unit each time I ride?

No, it's a one-time setup. After one (full) rotation, your wheels get active. Your control unit wakes up after a button press . After that, the coupling between the wheels and control unit is set automatically.

Will Gravaa advise me which tire pressure to choose?

During the initial setup, the app will ask you to enter details of your tires and a few other bits of information. Gravaa will intelligently suggest a starting or default tire pressure based on what you enter. Naturally, you are free to change these default settings. However, Gravaa won't let you set a higher pressure than the maximum rating of your tire, for obvious reasons.
Read more about optimal tire pressure here.

Why do you include a Presta interface?

You won’t need it often, but it’s there to give you the option to start your ride with the correct pressure (you can inflate using your standard bike pump if you want) or in case you have a flat tire. However, in almost all cases, there’s no need to use your bike pump anymore—just leave it to Gravaa.

Compatibility

Do you support my groupset?

When you order your Gravaa wheelset, you can select the correct freehub body for your groupset. We can deliver our wheelset with one of the following freehub bodies, which are compatible with the following cassettes:

  • Shimano Road HG 11 speed
  • Shimano Microspline 12 speed
  • Campagnolo Ekar 13 speed
  • SRAM XD
  • SRAM XDR

Can I display my tire pressure on my bike computer?

You can display the tire pressure (front and rear) on your bike computer using ANT+ or Bluetooth.

Are these wheels compatible with e-bikes?

Our wheelsets are intended for gravel biking and road biking and are not specifically designed for e-bikes. However, they may fit in bikes with a middle engine. Bikes with an integrated motor inside the hub will conflict with our wheels.

Are GRAVAA wheels compatible with all bike frames?

No, but the good news: we are compatible with most bike frames.

The following requirements apply:

  • non-boost hub spacing (100 mm front / 142 mm rear) will work,
  • Disc brake only: with rotor diameters from 140 mm to 180 mm,
  • Thru axles with diameter of 12 and 12 mm rear,
  • Freehub types for Shimano/SRAM 9-10-11 speed, Shimano Microspline 12 speed, Campagnolo Ekar 13 speed, SRAM XD and SRAM XDR.

Can I use my own thru axle?

Yes, you can use the one from your bike.

 

Can I use my own disc brake rotors?

No, we have designed dedicated Gravaa disc brake rotors, which are integral to the design and save weight. Our disc brake rotors are mounted with five bolts and are among the lightest on the market. The disc brake rotors are included as standard with your wheelset.

Can I still use my standard bike pump?

Yes, you can. There is still a Presta interface mounted, which fits your bike pump. You will not need it often, but it’s there to give you the option to directly start with the correct pressure (for example, before a ride you can pump it up using your standard bike pump), or in case you have a flat tire.

However, in most cases, there is no need to use your bike pump anymore. Just take your bike out for a ride as long as your tires are not too low in pressure: the GRAVAA wheels will automatically inflate your tires back to the last used setpoint while riding.

Can I ride with tubeless tires?

Gravaa wheels shall be compatible with tire sealants, as riding tubeless is widely used. As you can imagine, we do not want any of this substance to enter our system. The prototypes are undergoing intensive testing to make them function optimally.

Installation & Maintainance

How difficult is the installation of the wheelset?

Our wheels install just like any other wheels. There are no additional requirements. Simply tighten the wheel axles, pair the control unit with the wheels, and follow the in-app instructions for first-time setup. After that, it's time to ride.

Do Gravaa wheels require special maintenance?

All of the internal parts of our hubs are free of maintenance except for the following:

  • Standard wear parts in the wheels, like wheel bearings, which can be replaced. Please see the User manual for instructions.
  • Air filters keep the system clean from outside dirt so it functions properly. The system will automatically recognize when to replace filters and notify you. Replacement is easy. Spare filters will also be available via our webshop. Replacement instructions will follow.
  • Furthermore, you will need to charge your hubs occasionally to enable wireless communication and proper/safe usage. 


! On a serious note, please do not open the hubs yourselves, as this will invalidate your warranty (please check our service and warranty conditions here). If you have a product issue or would like to explore a topic in greater detail, please do not hesitate to contact us via our Contact form

 

Do I have to replace or charge any batteries?

The batteries inside the hubs are rechargeable. You can expect around 40 hrs of run time or ride about 1 to 3 months with full batteries in normal use. To prevent issues, we recommend charging batteries before each use of your wheelset.

Inside the control unit, there is a replaceable coin cell battery (type CR1/3N), which lasts for about 6-12 months, depending on usage. 
You can easily read the battery status of both wheels and the control unit from the Gravaa app.

Technical

How much energy does it cost me to inflate tires using Gravaa wheels?

The answer is simple: only a little. The exact power consumption when Gravaa actively inflates your tires depends on many factors, as the Technology page explains. On average, the power consumption is 4 Watts (per wheel) when inflating and 0 Watts when the system is no longer inflating (deflation requires no power, of course). The power Gravaa does draw (when active) is more than compensated by the advantages you will achieve by riding with adaptable tire pressure; with less friction/rolling resistance or improved traction, you stand to beat your friends or competitors.

 

How much energy does Gravaa draw when deflating my tires?

None whatsoever.

How long does it take to deflate my tires using Gravaa wheels?

This also depends on some factors (like inflation) but it’s so fast that you won’t notice it.

How long does it take to inflate my tires using Gravaa wheels?

The inflation time depends on several factors, including your tire size, riding speed, and the pressure difference you're adjusting between. As a general reference:
It takes approximately 800–1000 meters of riding to increase your tire pressure by 1 bar.

At a speed of 30 km/h, that’s roughly 2 minutes.

For more details on how the system works, check out the Technology page.

Orders & Shipping

When will I receive my order?

When all items from your order are in stock and your payment has been processed, your order will be packed and shipped as quickly as possible, usually on the same day. The expected delivery date is mentioned during checkout. We will notify you about your orders progress and shipping updates by email. 

Why do you not ship to my country?

While our goal is to be everywhere our customers ride, we have chosen to limit our coverage to the countries listed on our Shipping page to ensure a seamless service and experience. We aim to extend our coverage in the future, so stay tuned.

Shipping & Return Policy

The wheelsets are available for worldwide shipping.

Because we start on a build per order basis, items will be shipped as soon as the wheelsets are ready.  As soon as it’s possible, orders will be shipped directly. You will be notified as soon as your wheelset will be shipped, and you will receive a track & trace.

If and when you are a consumer (not professional trader) you are allowed to cancel your order within 14 days after the date of ordering. In case of cancellation, the provisions of our GENERAL TERMS AND CONDITIONS OF SALE AND DELIVERY apply. GRAVAA also has a cancellation policy which can be separately viewed below.