Thank you for your support by buying a Boost kit. We are committed to getting you on the road safely and as soon as possible! Please do not hesitate to drop us a line if you want any help with installation.

If you are not comfortable with any of the instructions here, please consider taking your kit to one of our growing network of partner shops - they will be pleased to help you out.

Installing your kit

Getting ready

  1. Unpack your kit. Check you have the battery, charger, battery mount and rear wheel, and that the rear wheel matches your expectations for size & colour.
  2. Plug in your battery to charge.
  3. Thoroughly clean your bike and chain.
  4. Check your existing chain for stretching using a chain measurement tool. Stretching should be less than 0.5%.

Fitting the wheel

  1. Remove your rear wheel. If it's a hub gearbox wheel you will need to detach the gear selector cable.
  2. Remove your rear tyre from your wheel and install it on your Boost wheel. Your new Boost wheel may not have rim tape installed - this will need to be transferred from your wheel.
  3. Make sure the valve type is the same. If you have a Schrader tube in your source wheel, you will need to replace it with a Presta version. Do not drill a larger hole in the wheel valve hole.
  4. Inflate your tyre.
  5. Nuts and washers; remove all washers prior to positioning the axle in the frame. We cannot provide instructions for every single frame but generally speaking the washers will be on the outside of the frame.
  6. Be careful at all times with the wire coming out the Boost wheel.
  7. Fit the new rear wheel to the bike, making sure the wire does not get caught or pass through the dropout slot. If it's a single speed you may need to find chain tensioners for your bike - this will be specific to your bike but note you will probably need 12mm tensioners not 10mm. Route the cable pointing forwards on the bike; make sure it isn't touched by the wheel (particularly the brake rotor bolts) as the wheel turns.
  8. On very narrow frames you may need to remove the plastic rotor substitute spacer and disc brake bolts. Be careful when replacing disc brake bolts without the spacer - the bolts may touch internal parts and cause damage so you may need to find shorter bolts to plug the holes. The holes should be covered to avoid water ingress.
  9. Once the wheel is in place, you can add the washers. Put the tab washer on first, tab facing inwards and into the open end of the dropout slot. Then add the plain washer, finally the nut.
Wheel with torque (tab) washer in place (highlighted in green)

Disc brake considerations

  1. Our hubs use a six-bolt pattern (not centre-lock). You will probably be able to reuse your existing rotor.
  2. Disc brakes - the position of the brake disc rotor is important and on some bikes we've found it's necessary to move the flat washer to the inside of the frame so that the disc rotor is in the correct place.
  3. You will likely need to move the disc brake caliper - this is normal for disc brake adjustments.

Fitting the battery mount

  1. Remove the battery from the battery mount.
  2. Remove your existing bottle cage. The battery mount can be installed on the seat post or down tube. The battery should not be installed slung underneath the frame.
  3. Lightly fit the bolts to the battery mount. Route the cable from the battery mount to the connector on the rear wheel. The cable is a standard length; it can be wrapped around the bottom bracket or seat post if you have excess cable. Just make sure it isn't touched by the wheel as that turns.
  4. Carefully align the controller cable connector with the motor cable connector - there is an arrow for alignment. Slide the connectors together - there is a line and the connectors must engage this far.
  5. Do not force the connector together - if it doesn't engage then you likely need to pull it apart and align carefully. You may need to wiggle it to release the air that gets trapped when pushed together.
  6. If you need to disconnect the connector, pull on the connector housing only - the wire is not strong enough.
  7. Once you have got the cable routed to your satisfaction, tighten the bottle cage mounts using the standard procedure and torque.

Fitting the battery

Warning: The battery must be locked into the battery mount when the bike is in use to prevent the battery jumping out of the mount.

  1. Lower the battery carefully into the battery mount and twist slightly until you feel it sit properly. It is possible to damage the terminals if you just drop it in.
  2. Use the key to lock the battery into the mount, again carefully and making sure the key turns fully.
  3. Lift the lid on the battery and turn on the switch. You should hear the Boost beeps as the system performs a self-check.

Downloading the app

Check the Support page for links to the Android & iPhone apps.

You're ready to ride!


The axle is too big for my frame, I think I need to file my frame to get it to fit

Do not file your frame! Solid axle & quick release bikes have a 10mm wide slot ('dropout') in the frame to install the wheels. The hub motor has a 12mm axle, with flat sections so that it can be slid into a 10mm dropout.

The valve hole in the wheel is too small for my inner tube

Please see the instructions above. If the inner tube will not fit into the new wheel it is because you have a Schrader valve inner tube, as used on cars. Wheels we supply have Presta valves which are smaller and more suited to bicycles. You will need to buy a Presta valve inner tube for your new wheel.

Click here for the full troubleshooting guide