Tube and Tire Service for Rear Motor Wheels

Tube and Tire service for Rear Motor Wheels
       For All Volt bikes with Rear Hub Motors

Tools/Parts Required:
18mm Wrench (or Adjustable Wrench)
10mm Wrench
Cutter
Zip Ties
Plastic Tire Levers
Pump
New Tube/Tire 

1. Introduction

Since the creation of the pneumatic bike tube & tire the dreaded ‘flat tire” has been a reality that every cyclist must deal with at some time or another. Despite puncture resistant tires, tire liners, and liquid sealers, nothing is 100% impenetrable to the thumb tac, the blown sidewall , and the all popular blackberry thorn. Every able cyclist should know the basics of how to remove a wheel and change a flat tire in case they find themselves stuck far from home or local bikeshop.


The Front Wheel

For most Voltbikes, removing and installing the front wheel is no different than the front wheel of a regular bicycle that has a front quick release skewer or axle nuts. Once a front tire or tube is replaced ensure the wheel is re-installed properly all the way up in the drop-outs and is centered in the fork. The quick release lever must be firmly and fully closed. The threaded nut may need to be re-adjusted by a few turns to ensure the closed lever tension is correct. Visually re-check the wheel is centered and use your fingers as a guide to confirm equal spacing on each side. Spin the wheel to ensure the disc brake rotor is centered in the brake caliper and the front brake is functioning correctly. Never squeeze
the hydraulic brake lever when the wheel and brake rotor are removed.





The Rear Wheel

Removing the (rear hub motor) wheel of your Voltbike is a slightly more technical job that requires a few extra tools and extra attention to details. The first attempt will be the most challenging and typically gets easier with a bit of practice. Having the right tools, a workspace, and a bike stand (or friend) to position the bike off the ground will help. If needed, carefully turn your bike upside down to rest on the handlebars, but ensure the LCD screen, controls, or saddle are not damaged.

Some key things to keep in mind before starting the repair are:
• Remove the battery or ensure your bike is turned off
• Be careful not to damage the rear motor cable and plug
• Visually check the orientation and order of spacers and anti-spin washers
on the rear axle before you remove the rear wheel. Take a photo if
needed.
• Know the size of the tire and tube that is compatible with your bike
• Common tube/tire sizes:
        20” x 2.0” - 2.2”        26 x 2.0 - 2.2       27.5 x 2.0 - 2.4
            20 x 4.0                   26.0 x 3.0             27.5 x 3.0
                                            26.0 x 4.0 

See below for details about diagnosing a flat and replacing the front or rear tube and tire.

2. Remove The Rear Wheel from the Frame

To remove the rear wheel, uninstall the chainstay pad, cut zip ties, and carefully
disconnect the main power cable from the rear hub motor. 



Position the 7sp thumb shifter into the high gear (small cog)



Use a 18mm wrench to loosen and fully remove the axle nut and flat washer from the drive side.



Next use a 18mm wrench to loosen and fully remove the axle nut and flat washer from the non-drive side.




To uninstall the rear wheel from the frame’s drop-out use a 10mm wrench (or small crescent wrench) on the axle flats and firmly wiggle the axle while pulling back on the rear derailleur. This will ensure the rear derailleur and chain do not interfere with the 7sp freewheel while the rear wheel is being removed from the frame. The wheel’s brake rotor should slide straight out of the rear brake caliper. Do not squeeze the rear hydraulic brake lever while the rear wheel is removed from the bike.

Wiggle the axle using a 10mm wrench



Pull back on the rear derailleur



Remove the rear wheel from the frame’s drop-outs 



CRITICAL: Remove any inside spacers, and anti-spin washers. Keep the driveside and non-drive side spacers separate and note the order and orientation of
the anti-spin washers and any spacers. This will ensure no spacers are lost or
misplaced while the flat is being repaired. 

3. Remove The Tire and Tube from The Rim

Remove the valve cap and any remaining air from the tube. Next uninstall the tire and tube from the rim. Some tires can create a tight seal with the aluminium rim wall and must first be separated before the tire can be removed from the rim. Use your thumbs to firmly push the tire away from the rim sidewall on both sides. 



Start to remove one side of the tire bead from the rim wall using plastic tire levers.



Once one side of the tire bead is fully off from the rim, the second side of the tire can be removed more easily. 



Uninstall the tube and tire from the rim by hand. This is a good time to check the rubber or nylon rim strip that covers the inside spoke holes. 

4. Determine The cause of the Flat

Attempt to locate and diagnose the cause of the flat tire/tube. The type of hole can help identify the possible cause of the flat:
         • Puncture hole- nail or thorn type puncture
         • Tear – tube seam or tire side wall
         • Snake bite – two holes in tube, pinch due to low tire pressure
         • Valve stem - damaged stem valve or sharp edge in rim hole

Examine the tire carefully for wear or small sharp objects both outside on the tread and inside the tire. Reinstalling a new tube without knowing the reason for the flat may result in a second or even third flat from the same cause. Small pieces of metal or glass can be embedded in the tire tread and require a careful visual and hand inspection using your fingers to feel for small sharp objects. 

5. Installing The Tube and Tire

Once the cause of the flat has been determined, a new tire and/or tube can be installed. Ensure the new tube or tire size is compatible with your rim and bike frame. The tire size and pressure range is located on the tire sidewall. Typically most Voltbikes use Shrader style valves but Presta valves will also work. 



Note: Most tires have a rolling direction also shown on the sidewall.



First pump up the tube just enough to take shape and make it easier to install.



There are a few ways to install a tire and tube...we recommend you fit the tube inside the tire, check the rolling direction, place the valve stem through the rim hole, then proceed to get one side of the tire bead fully on the rim. 



Next, flip the wheel over and start near the valve stem to install the other side of the tire bead onto the rim. Typically it’s to best to work by hand in both directions and finish opposite from the valve hole. Be careful not to pinch the tube between the tire and the rim wall. A plastic tire lever or strong hands may be needed to push the last portion of the tire bead onto the rim as it is may be a tight fit.

6. Seating The Tire

To ensure the tire is seated evenly, add a small amount of air and go around the tire checking that the tube is fully inside the tire and not interfering with the rim strip. Massaging the tire and tube side to side on the rim can help to balance and seat the tire. Once in place, pump the tube up to half pressure and check the tire by spinning the wheel. There should be no major bumps, high or low spots, or areas where the tire appears to be coming off the rim. Seating a tire properly can be challenging and may require pumping the tire up to a higher pressure (listen as it pops in place) or using a soap solution to help seat the tire bead. Do not use WD40 or oils to seat your tire!

Once the tire is properly installed on the rim it can be inflated to full pressure as noted on the tire sidewall. Riders should check their tires for tread wear and pressure at least once every thirty days.

7. Reinstall The Rear Wheel in the Frame

Critical: First ensure all the inside axle spacers and anti-spin washers are installed and orientated correctly.



Align the brake rotor with the brake caliper to reinstall the rear wheel in the frame. The chain should be positioned around the small cog. Use a 10mm wrench to align the axle flats with the drop outs and push the wheel straight up into the dropout slot.



Once the wheel is seated fully in the dropouts, the non-drive side axle washer and nut can be installed and partly tightened with an 18mm wrench. Next install and tighten the drive side washer and nut. Check the rear wheel is centered in the frame and the brake rotor with the caliper. Recheck both axle nuts are very tight. Recommended install torque 45-55 N*m

Tip: a small drop of oil on the axle nut threads will make the nut easier to tighten. 

8. Reconnect The Rear Hub Motor

Install the rubber axle nut covers (if available), align the power cable plug arrows, and firmly connect the rear hub motor plug. Secure the motor cable with zip ties and/or chainstay pad.

9. Test Ride and Check

Test ride to ensure the bike is safe and functioning properly! This includes checking the brakes and shifting. A minor adjustments to brake and shifting may be required. Recheck the axle nuts are tight after 24 hours riding time. Failure to properly re-tighten a rear hub motor wheel may cause the motor to come loose over time and potentially damage the bike frame. 



For a PDF Version of this article complete with photos: Click Here