Hightekbikes Motor Kit Installation Instructions
This motor kit must be mounted on steel (chromalloy) front
forks. Aluminum (alloy) forks are not suitable as aluminum is very brittle and
can not take the stress. The dropouts can break off, causing serious injury.
If you are not sure, use a magnet to test. The magnet will stick to steel but
not aluminum. If your donor bike has the common aluminum suspension fork, it
can be replaced with an appropriate steel rigid fork. When you order the new
fork, make sure you specify it is replacing a suspension fork so the geometry
will be maintained. An alternative would be to just choose another one of the
fine bikes that are available with a rigid steel fork.
is not responsible for damage or injury as a result of installing the kit on an
Do not attempt to power the motor until it is mounted in the
fork and the nuts are securely tightened. Damage to the wires will result,
which will void the warranty.
Part I – Remove existing
wheel and check fit for new wheel
- Turn bike upside so it is resting on the handle bars and
seat. If necessary, loosen and move any bells or lights mounted on the
bar so they won’t be damaged, or place a towel or blanket under the handle
- Loosen the front brakes by pulling the curved bar out of
the retaining bracket so the brake arms are fully extended away from the
wheel. Loosen the nuts on the wheel and remove. You might have to let
some air out of fat tires to get it past the brake pads.
- Loosen the nuts on the motor kit wheel and place the wheel
into the fork to check the fit. The most common arrangement of the
washers is to have the flat washer inside the fork next to the motor, then
on the outside of the fork is the torque washer, then the nut. This is
the recommended setup for dropouts with a flat surface for the nut and
lock washer. If the axle fits in the dropout and the washers lay flat,
continue on to the next step. Note: the dropout is the end of the fork
where the axle fits into the U-shaped opening.
Condition: Axle does not fit into dropouts
First make sure the flat part of the axle is aligned
properly in the dropout. If it looks like a close fit but the dropout is just
a little too narrow, you can widen it slightly. Take a flat file and carefully
file a small amount from each side of the dropout, being careful to keep the
file parallel to the dropout. You want this surface to be absolutely flat.
Don’t over do it, you want the axle to be snug to slightly tight.
Condition: The outside of the dropout has a ridge,
preventing the torque washer from laying flat.
Many new bikes come with quick release hubs these days. The
dropouts often have a circular ridge where the round nut goes onto the quick
release mechanism. The problem is that this prevents the torque washer from
seating properly. There are two possible solutions. If the dropout is thick
and strong, and the ridge is short, maybe only a quarter to a half circle, you
can file it down until flush with the main surface. If the ridge is more than
half a circle, and or the dropout is relatively small and thin, it is not
recommended to do any filing. Instead, insert an extra lock washer (the normal
split kind) onto the axle first, then the nut. The lock washer will fit into
the ridge allowing the nut to grip against both the lock washer and the ridge.
Since the lock washer will move the torque washer too far away from the dropout
to be effective, you have to instead move it to the inside of the fork. So now
the order is: on the inside of the fork, next to the motor, is the torque
washer with the tab facing out. The flat washer is removed and not used. On
the outside of the dropout goes the regular lock washer then the nut. An
alternative to the standard lock washer is the toothed washer with the teeth
facing inwards. This type works well when the standard lock washer doesn’t
fit. As shown below, it will compress and deform into the recessed areas
allowing the nut to grab tightly. Another option is to add a second torque
washer on the outside of the fork. This provides additional insurance against
an axle spin. For extra heavy duty use, a torque arm is recommended (not
Part II – Install New
1. At this point you have fitted the wheel to the fork.
Remove the wheel and put aside for a moment. Retrieve your original wheel and
remove the tire, tube, and the tube protection strip from the wheel. Place
these on your new wheel. If your treads have a pattern that is designed to rotate
in one direction, make sure it matches the rear wheel.
2. Install the assembled wheel into the fork. There are two
possible ways it will go in. You want the motor wires exiting down towards the
road. As you look at the bike upside down, the wires will be facing up. Also
make sure the wires are on the right side of the bike when you are normally
sitting on the bike.
3. Make sure the axle is all the way into the dropouts and
the wheel is centered. Verify the washers are in the proper place and torque
down the axle nuts. With an eight to ten inch wrench, you want to tighten as
tight as you can without bracing yourself or leveraging.
4. Turn the bike right side up.
Part III – Install
- Determine where to mount the controller by holding it in
various places to see where it will fit. First, check under the rear rack
for clearance. If it doesn’t fit, check to see if you can raise the
rack. Note: if you didn’t already install the rack, do so now. If that
won’t work, check the mounting brackets for the rack that attach to the
seat post area. It can go on top of these or under if there is room.
Another possibility is the seat post bar between the bottom bracket and
the seat. It can go behind or in front of the bar, whatever fits and looks
- After determining the best location, mount the controller
using bolts or cable ties. Use one inch pipe mounting clamps to secure
controller to the bar seat post. When mounting in the rack area, you can
use cable ties or bolts on the controller brackets. It might be required
to drill holes in the rack.
Part IV – Install Throttle
and Brake Levers
- Remove the handle bar grips. The easiest method uses soap
and water to loosen the grips. Take a handy wipe, or paper towel soaked
in soapy water, and force it under the grip with a flat head screw
driver. Being careful not to scratch the bar, work it around pushing it
at least half way under the grip. Start turning the grip and work the
water around. When enough of the grip is coated , it will slide right
off. Wipe the water off the bar.
- Remove the brake levers. Detach the cables from the
handles but not the brake assembly. Replace the brake handles with the
ones from the kit and insert the cables.
- The throttle has a small hex screw that tightens it to the
handle bar. Find the correct Allen wrench and loosen the screw until it
does not protrude into the inner circle that the handle bar goes through.
Before mounting the throttle, take a look at the brake handle and any
shifter. Determine the best order for easy access to all three controls.
Generally you want the throttle next to the hand grip. Usually the brake
comes next. If that looks good, then just loosen the brake and shifter
and shift them down the bar to allow room for the throttle. Slide on the
throttle, allowing enough room for the grip. Align it so the LEDs face up
and toward the rider and tighten the Allen screw. Slide the brake lever
and shifter back up the bar and tighten. Slide on the hand grip, leaving
a small space between it and the throttle so it doesn’t bind.
- Run the wires from the throttle and brakes back to the
controller. Use the included tie-wraps to secure the cables to the frame.
Part V – Connect Wires to
- You have run the wires back to the controller which is
mounted to the frame. All the connectors are different so you can’t plug
something in wrong. Do not plug the battery in yet. Connect the
throttle (4-pin) and the brake cable (2-pin) to the controller
connectors. Run the motor cable from the controller to the motor. Don’t
fasten with the cable ties yet but run along the frame in the proposed
location. Slide one of the large diameter shrink wrap strips over the
connector and back it onto the cable. Connect the cable to the motor
connector which is tie-wrapped to the fork. Now slide the shrink wrap
over the two connectors. What you want to do is heat up the top part only
with a heat gun or hair dryer. This will seal up the top half but allow
you to still slide it up to get access to the connector. Optionally, use
one of the small tie wraps to fully close the top edge of the shrink
wrap. Working from the front fork back to the controller, use tie-wraps
to secure the motor cable to the frame. You can secure it to the brake
cables or to the frame as needed. As you make the turn from the fork to
the main tube, put an extra two to three inch loop to allow slack for
- You have run all the cables back to the controller.
Gather the excess cable lengths and either fold or coil them so they are
about 3 to 4 inches in length. Cover with the large shrink wrap and
secure this bundle to the frame. You might have to separate the wires
into two bundles. This protects the connectors from dirt and moisture and
makes for a clean installation.
- The one cable not connected goes to the battery. If you
haven’t already, connect the pigtail into the controller power connector
(“trailer hitch” type). This will have Anderson connectors on the battery
side. If more length is needed, you will have to make an extension
cable. We can supply this for a nominal charge..
Part VI – Adjust Brakes
- The width of the new rim might be a different from the
original, so you might have to adjust the brakes. You previously detached
the curved tube holding the two brake pad assemblies together so they are
extended out away from the wheel. Using an allen wrench, loosen the brake
pad. Hold the pad against the rim and move around until it seats in the
proper place. While holding it against the rim, tighten the brake pad.
After repeating for the other side, insert the curved tube into the
bracket. It there is not enough slack, loosen the cable bolt, and let out
enough cable until there is about 1/8” of play before the brakes hit the rim
and re-tighten. Test the brakes and make sure they are working correctly.
Part VII – Connect Battery and Testing
- Place the battery pack into the battery bag and attach it
securely to the rear rack. Make sure the controller is turned off and plug
the pack into the controller. Make sure the polarity of the wires is
correct; red to red and black to black. When you plug the pack into the
controller, you may see a spark due to the current inrush caused by the
capacitors in the controller quickly charging up. You can add a high
power switch or relay in series with the power cable to prevent this. We
will also be offering an electronic switch in the near future.
- Switch on the controller. You should see a red LED on
continuously and the green LED should be blinking slowly.
- Lift the front wheel off the ground and slowly press the
throttle. The wheel should go backwards for a split second as the
controller determines the motor position, then spin forward smoothly.
- Take the bike for a short test ride, working the throttle
gradually and only going a few blocks. Re-check the tightness of the
front nuts and the wiring. Make sure the battery pack is tightly secured.
- After a few weeks of riding, check the wheel alignment and
verify it is true (straight). Also check for loose spokes and make sure
the nuts are tight.
Part VIII – Maintenance
- The motor is sealed and does not require lubrication. It
is a brushless motor and has no gears. Do not go through deep puddles or
submerge the motor in water as it can enter the motor through the cable
- Do not allow any of the electrical components to get wet.
Cover the controller, throttle, and battery with plastic bags during
rain. It is recommended not to leave the bike outdoors for long periods
of time due to condensation.
- Be careful not to let the wires coming out of the motor rub
against the axle area. The wires should exit straight and be secured to
the fork. If the wires are pulled to one side, they might be susceptible
to having the insulation worn off, causing a short.
- Check the tightness of the axle nuts regularly. If they
become loose, the axle might spin in the dropouts, twisting and cutting
the wires. This is an expensive repair and is NOT covered under warranty.
Part IX – Troubleshooting
- The motor controller has two LEDs that aid in
troubleshooting problems. The red LED indicates power is turned on to the
control circuitry. It should stay on continuously after flipping the
power switch. The green LED is a status indicator and will indicate
Steady blink: Connections are
correct, throttle off.
Steady on: No errors, throttle on.
Slow 2-pattern blink: Brake
cut-off switch engaged.
Slow 6-pattern blink: Error. Can
not detect motor position.
Slow 8-pattern blink: Low voltage
Cutoff reached (LVC). Battery low.
Thank you for your purchase. This
quality kit will provide you with years of service.
Happy eBiking !
© 2009 Hightekbikes, Inc. www.hightekbikes.com