Retrospec KOA REV+ User manual

Koa
Electric Fat Tire Bike - 750W
Assembly Instructions
ENGLISH | FRENCH

List of E-Bike Component Names
1. Tires & Tubes
2. Rims
3. Spokes
4. Front Hub with QR
5. Front Mechanical Disk Brake
6. Front Suspension Fork
7. Front Mudhuard (Fender)
8. Shift Lever & Brake Lever
9. Handlebar & Stem
10. Display
11. Throttle
12. Grip
13. Front Light
14. Frame
15. Saddle
16. Seatpost
17. Seat Post Clamp
18. Rear Light
19. Rear Mudguard (Fender)
20. Rear Mechanical Disk Brake
21. Rear Motor Hub
22. Kickstand
23. Freewheel
24. Rear Derailleur
25. Chain
26. Controller
27. Chainwheel/Crankset
28. Pedal
29. Battery
Fig. 1 Electric Bicycle
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1

Before your first ride
We strongly recommend taking your bike to a local bike shop after assembling
so a professional, reputable bike mechanic can check your work and perform all
necessary safety checks prior to the rst ride. To nd a Retrospec dealer near
you, please visit https://retrospec.com/pages/store-locator.
Please keep these instructions for future use & reference. Do not discard.
Congratulations on your purchase of this Retrospec electric bike! We make sure
all of our e-bikes have been carefully designed and manufactured to the latest
international quality standards.Please read this instruction manual carefully
and thoroughly before riding. It contains important information on safety, and
maintenance and it’s the owner’s responsibility to read this manual before riding
and keep it for future reference.
This user’s instruction manual includes two sections:
SECTION I - Mechanical Operation, and SECTION II - Electric Operation.
These instructions apply to electric bike models with following equipment:
Section I:
Mechanical Components Operation • Derailleur with Disc Brakes
For mechanical equipment, an electric bicycle diers only slightly from a
non-electric bike.
Section II:
Electrical Components Operation
• The battery-pack mounted on the down tube
• The motor in the rear wheel hub
• The controller box is inside the frame
• Handlebar-mounted Display Panel operations.
2

Warranty:
Should any original component prove defective in terms of workmanship within its
warranty period, we will replace it. Warranty period for Retrospec electric bikes is
as follows:
• Electrical Components excluding Battery: 2 years with proper maintenance
• Battery: 1 year
• Frame and Fork: 1 year
• All Other Components: 6 months
This warranty does not include labor and transportation charges. The company
cannot accept any responsibility for consequential or special damage. This
warranty applies only to the original retail purchaser who must have a proof of
purchase in order to validate any claim. This warranty applies only in the case of
defective components and does not cover the eects of normal wear, nor damage
caused by accident, abuse, excessive loads, neglect, improper assembly, improper
maintenance or the addition of any item inconsistent with the original intended
use of the bicycle.
No bicycle is indestructible and no claims can be accepted for damage caused by
improper use, competition use, stunt riding, ramp jumping and leaping or similar
activities. Claims must be submitted through your retailer. Your statutory rights
are not aected. The company reserves the right to change any specication
without notice. All information and specications within this manual are correct
at time of printing.
Section I -
Mechanical Components Operation, Maintenance, & Safety
Contents:
1. Conditions for riding this electric bicycle
2. Saddle and handlebar set-up
3. Safe cycling and safety tips
4. Routine maintenance checks and lubrication
5. Assembly instructions
1. Riding Conditions
This pedal electric assistance bicycle is designed for riding on road, or paved
surfaces where the tires have rm contact with the riding surface. This e-bike
must be properly maintained according to the instructions found within this
manual. The maximum weight of the rider and load is 350lbs (159kgs).
3

WARNING! The owner/rider assumes the risk for personal injury, damage,
or losses. If the conditions in this manual are breached, the warranty will be
void automatically.
2. Saddle and Handlebar Set-Up
The saddle can be easily moved either up or down. Adjust the saddle to
keep the rider’s knee maintaining a slight bend when the foot is in the lowest
(6 o’clock) pedaling position (Fig.2). To position the saddle fore and aft saddle
position see (Fig. 3).
3. Safe Cycling and Safety Tips
3.1 Pre-Ride Check Points
Before you ride your pedal electric assistance bicycle always make sure it is in a
safe operating condition. Particularly check that your:
• Nuts, bolts, quick-releases and parts are tightly fastened, not worn,
damaged or loose.
• Riding position is comfortable and unencumbered.
• Brakes are operating eectively.
• Steering is free with no excessive play.
• Wheels run true and hub bearings are correctly adjusted.
• Wheels are properly secured and locked to frame/fork.
• Tires are in good condition and inated to correct pressure (tire pressure
;in on tire sidewall—do not exceed max tire pressure).
• Pedals are securely tightened to pedal cranks (NOTE: left side is reverse
thread. Turn left to tighten).
• All reectors are secure and in position.
Fig. 2 Fig. 3
Knees slightly
bent
Handlebar stem
approximately
level with seat
or slightly lower
Loosen saddle from seat
pillar to adjust forwards
or backwards. Tighten
when set correctly
The saddle should be moved forwards or
backwards so that the knee is directly above
the pedal when crank is parallel to the ground
Pedal at bottom
4

After you have made any adjustment to your electric bicycle, check that all nuts
and bolts are securely tightened and cables are free from kinks and xed securely
to the electric bicycle frame. Every six months, your electric bicycle should be
professionally checked to ensure that it is in correct and safe working order. It
is the responsibility of the rider to ensure all parts are in working order prior to
riding this electric bicycle.
3.2 What Never To Do When Riding
• NEVER ride without wearing an approved helmet, which must meet
lUSA/European (CPSC/EN) standards. Always comply with the local laws
lland ordinances.
• NEVER ride on the same side of the road as oncoming trac.
• NEVER carry a passenger as this bicycle is designed for a single rider only.
• NEVER hang item(s) over the handlebar as this could interfere with steering
or catch in the front wheel causing a crash.
• NEVER hold on to another motor vehicle or bicycle.
• NEVER ride too close to another vehicle—stay aware and keep your distance.
WARNING! Wet Weather Riding: Your bike’s brakes do not work as well under
wet or icy conditions as they do under dry conditions. The braking distance in wet
weather will be longer than that in dry conditions. Take special precautions in wet
weather to assure safe stopping. Ride slower than normal and apply your brakes
well in advance of anticipated stops.
WARNING! Night Riding: Do not ride at night. If
you have to be on your e-bike at night or in low-light
conditions, always comply with laws and regulations
(local and otherwise) for bicycle lighting. Use
approved headlights (white), taillights (red) properly
axed to your e-bike in addition to all-around
reectors. For additional safety, wear light colored
clothing with reective stripes, or safety yellow or
safety orange clothing. Check that the reectors are
rmly secured in the correct position and clean and
not obscured. Damaged reectors must be replaced
immediately.
WARNING! The seat post must be inserted at
least up to the minimum insertion mark, or further
so the insertion line is no longer visible (Fig. 4).
If not, the seat post may bend or break, possibly
damaging the bicycle or causing injury.
m
Minimum
extension
mark
Fig. 4
5

WARNING! Handlebar stem minimum insertion mark on traditional quill stem
must NOT be visible above the top of the headset. If the stem is extended beyond
the minimum insertion mark, the stem may break or weaken the fork steering
tube, possibly damaging the bicycle or causing an accident (only for bike equipped
with a quill stem).
4. Routine Maintenance Check and Lubrication
WARNING! As with all mechanical components, your bicycle is subjected
to wear and stress. Dierent materials and components may react to wear or
fatigue in dierent ways. If the design life of a component has been exceeded
it may suddenly fail, possibly causing injuries to the rider. Any types of cracks,
scratches, or change of coloring in highly stressed areas indicate that the life of
the component has been reached and it should be replaced immediately.
Always inspect your bicycle before every ride.
WARNING! Use only genuine replacement parts, particularly for safety-
critical components, installed by a professional bicycle mechanic. To keep your
electric bicycle functioning well, the following routine maintenance lubrication is
necessary (refer to Fig. 5):
Half-Yearly: Remove,
clean, and lubricate chain,
derailleur(s), cog set, and all
cables. Check and replace
as required.
Weekly (or as needed):
Wash bicycle with warm
soapy water. Dry with a
soft, nonabrasive cloth. Do
not use strong chemicals
or abrasives. Do not use
a high-pressure washer.
Inspect your bicycle while
cleaning.
WARNING! Every six months, your pedal electric assistance bicycle should be
professionally checked to ensure that it is in correct and safe working order. It
is the responsibility of the rider to ensure all parts are in working order prior to
riding.
Fig. 5
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6

5. Assembly Instructions
Following is important information and instructions for assembling and maintaining
your new electric bicycle.
Step 1: Unpacking Your Bike
• Open the box. You may need a box knife to cut tape. Watch-out for staples
and sharp edges as you lift the bike out of the box. A helper can make this
easier. Do not lay the box out at and cut the bike out as you may damage the
bike. HOT TIP: Use needle nose pliers to remove the staples before pulling the
bike out of the box. This will insure they do not scratch you or the bike.
• Cut all packing zip ties. Detach all parts that are tied to the frame. Be careful
not to cut/scratch the bike, particularly the tires and cables when removing
the ties.
• Do not attempt to rotate the handlebar/fork until all zip ties and packing have
been removed, otherwise you may damage the bicycle. Carefully examine
the carton for loose parts and make certain that no parts are remaining in
the box. Keep the box and packing material for a short time in case the bike
needs to be returned.
• Examine your new bike for any visible damage which may have occurred
during shipping.
01 - Tires
Check for cuts and wear,
maintain pressure indicated
on tires wall for maximum
eciency.
09 - Stem and Handlebar
Ensure stem nuts and bolts
are tight. Check handlebar
bolt is tight. Check brake lever
securely mounted to bars and
brakes stop smoothly and
eciency.
25 - Chain
Lubricate as needed (this will
depend on usage and riding
conditions).
02.03 - Wheel
Check that axles are sealed and
secured properly. Rim should be
kept free from wax, oil, grease,
and glue. Check for loose or
missing spokes, (see warning
below).
10.11.21.26.29 -
The Electrical Parts
You can refer to the manual for
electrical parts.
27 - Cranks
Check for loose bolts on both
arms and rings.
04 - Wheel Hub
Grease bearings annually. Adjust
cones to avoid free play side to
side without binding.
12 - Grip
Check that they are clean and
tight.
28 - Pedals
Check for looseness.
NOTE: left side is left-hands
thread.
7

Step 2: Fender, Headlight and Front Wheel Installation
2.1 Installing the Front Fender and Headlight
1. Unwrap both the fender and the headlight.
2. Locate the long bolt, washer, and nut which will either be in the parts bag/
box or inserted in the top of the fork. If it is threaded into the top of the fork
arch, remove it using the 5mm hex wrench.
3. Slide the tab at the top of the fender in front of fork arch hole at the back.
Place the light mounting bracket on top of the fork tab in the same position.
Insert the bolt through both and snug tight with the 5mm hex. (Fig. 6)
4. Position the fender struts to the mounting tabs on the fork. It is okay to
squeeze inward as these braces are designed to be pliable. Using the 4mm
hex and 8mm open end wrench, unthread the mounting bolts. Run the bolt
through the open end of the strut and x the fork mounting tab. Thread
the nut onto the back of the bolt and snug tight with the 4mm and 8mm
wrenches. (Fig. 7)
5. Check that the fender and light are level and straight and tighten the fork
arch mounting bolt using the 5mm hex wrench. We will tighten the struts after
installing the front wheel, which is up next.
Fig. 6 Fig. 7
8
2.2 Installing the Front Wheel.
1. Remove the plastic dropout protector from the fork. (Keep this in case there
is a need for a return.) (Fig. 8)
2. Inate the tire to make centering the wheel in the fork easier. The tires range
is 5-30PSI (point 4 below).
3. Using the 17mm open end wrench, loosen the axle nuts on the front wheel.
Lift the front of the bike and insert the front wheel into the fork dropouts (a
helper can make this easier). Make sure the washers are also between the nut
and the fork and not the fork and the hub. (Fig. 9)
4. Inspect the wheel to make sure it is centered in the fork and the rotor is
situated in the brake caliper. Tighten each axle nut a little at a time (17mm or
adjustable wrench), alternating between sides until each axle nut is properly
tightened.

Step 3: Seat Assembly (Refer to Fig. 8)
3.1 - Assembling the Saddle onto the Seatpost:
1. Loosen the seat clamp nut.
2. Insert the seat post into the seat
clamp. Make sure the seat post is rm
against the seat clamp limit and seated
into the rails of the saddle.
3. Re-tighten seat clamp nut (hand tight).
4. Insert the seat post into the frame seat
tube and rotate the saddle until the top
of the saddle is level to the ground. You
can nish tightening the seat now or
after Step 3.2. Do not sit, or test saddle
until completing Step 3.2!
WARNING! The seat post must be
inserted into the seat tube at a depth where
the minimum insertion line is not visible!
3.2 Inserting the Saddle/Seatpost
Assembly Into the Frame Seat Tube,
Quick-Release Seatpost Clamp:
1. Open the seat post quick release lever (Fig.9). Apply a small amount of
grease to the seatpost. Insert the seat post into the seat tube to sucient
depth so that the minimum insertion line is no longer visible. NOTE: The lever
should require some force to close. If it closes too easily and does not hold
the seat post in place, or if the eort to close the clamp is too great, adjust
the clamping force by loosening or tightening the adjusting nut on the side
opposite the lever.
2. When you are satised with the height of the seat post, close the seat post
quick release lever. The tightness of the lever is adjusted by rotating the
adjustment nut opposite the quick.
Seat
Clamp
Seat
Post
Seat Tube
Top tube
Seat Post
Binder Bolt
and Nut
Seat Clamp Nut
Tip of Seat
Minimum
Insertion Line
Fig. 8
Fig. 9
Adjustment Nut
Closed
Open
9
4. If the fender is not straight, or rubbing the tire, that’s okay! the fender braces
can be adjusted or bent to center the fender. Gently adjust the fender by
hand until it’s straight. Tighten the strut xing bolts at this time.
NOTE: Rear Fender Adjustment: The rear fender is installed at the factory and
should be good-to-go. However, it may require some small adjustment due
to shipping. Follow 2.2 step 4 to straighten as necessary or a combination of
loosening the brace end bolts, retightening, and centering

2.2 Installing the Front Fender
1. Locate the long bolt, washer, and nut which will either be in the parts bag/
box or inserted in the top of the fork.
2. Slide the fender in place from the back of the fork. Insert the long bolt
through the top/center fork hole from the front of the bike. At the rear of the
fork hole, place the bolt through the fender mounting tab with the washer
and nut. While pushing the fender tab up as far as it will go, tighten the bolt
and nut to secure the fender to the top of the fork (Fig. 10).
3. Position the fender braces to the mounting holes on the fork dropouts. It’s
okay to squeeze inward as these braces are designed to be pliable. Partially
thread the screw through the fender brace end hole and into the dropout—
repeat for the other side. When both braces are partially attached, tighten
the brace screws to complete the install (Fig. 11).
4. If the fender is not straight, or rubbing the tire, that’s okay! As mentioned
above, the fender braces can be bent to center the fender. Gently adjust the
fender by hand until it’s straight.
NOTE: Rear Fender Adjustment: The rear fender is installed at the factory and
should be good-to-go. However, it may require some small adjustment due
to shipping. Follow 2.2 step 4 to straighten as necessary or a combination of
loosening the brace end bolts, retightening, and centering.
Release lever. Turn the nut by hand to adjust the tension while holding the
lever stable.
Fig. 10 Fig. 11
10

Step 4: Handlebar & Handlebar Stem Assembly (Refer to Figs. 12 & 13)
The handlebar has been pre-assembled together with brake levers, shifter levers
and grips. Be sure that the longer cable is xed to the right lever (rear brake) and
shorter cable to the left (front brake). (NOTE: In some areas, such as the UK, the
cables are required to be arranged in the opposite way).
Your e-bike may be tted with an
adjustable stem, a standard quill stem,
or a threadless stem (Refer to Fig. 12).
Regardless of stem type, always check
that all the bolts are tight before
riding. Respect the stem type and
follow the instruction below:
1. For Quill Stem: Insert the
handlebar stem into the fork
steer tube to the minimum height
line that is marked on the side
of the handlebar stem. It may be
necessary to loosen the stem
Expander Bolt so that the stem
can slide into the fork tube, until
you get your desired height of the
handlebar stem. For Threadless
Stem: Slide the stem over the fork
steer tube.
2. Align the handlebar stem with the
front wheel (See Fig. 13). Securely
tighten the stem bolt(s). Note:
Some models require a 6mm hex
key. (Tightening torque: 18N.m or
14foot lbs.torque).
3. Positioning the Handlebar:
• Loosen the stem handlebar
clamp bolt (Quill) or hex bolts
(Threadless).
• Position the handlebar at the
desired angle. Make sure the
handlebar is in the center of the
stem handlebar clamp.
• Tighten the handlebar clamp
bolt (tightening torque: 18N.m or
14footlbs.lbs).
4. Be sure that your handlebar
and stem assembly is properly
tightened before riding. The
handlebar and stem should not
rotate in the stem up or down or
in the fork.
Compression Bolt
Compression Cap
5 Star Washer
Extension
Bearing Seat
Expander Bolt
Handlebar
Clamp Bolt
Handlebar Stem
Reector
Fork Tube
Center Line
Handlebar
Front Wheel
Expander Wedge
Top Cups with
Bearings Inside
Spacers
Stem
Bolt
Fig. 12 (Threadless)
Fig. 12 (Quill)
Fig. 13
11

Step 5: Installing Pedals (Refer to Fig. 14)
The pedals are marked with either a “R” (Right) or “L” (Left) on the threaded end
of the pedal axle.
Screw the pedal marked by” R” into the right side of the crank assembly (chain
side of bicycle). Turn the pedal (by hand) in the clockwise direction. Tighten
securely with a 15mm open-end, 15mm pedal specic wrench, or adjustable
wrench (tighten to torque: 34N.m or 26 lbs.).
Screw the pedal marked by “L” into the left side of the crank assembly. Turn the
left pedal (by hand) in the counterclockwise direction. Tighten securely with a
15mm open- end, 15mm pedal specic wrench, or adjustable wrench (tighten to
torque: 34N.m or 26 lbs.).
The handlebar has been pre-assembled together with brake levers, shifter levers
and grips. Be sure that the longer cable is xed to the right lever (rear brake) and
shorter cable to the left (front brake). (NOTE: In some areas, such as the UK, the
cables are required to be arranged in the opposite way).
Your e-bike may be tted with an adjustable stem, a standard quill stem, or a
threadless stem (Refer to Fig. 12). Regardless of stem type, always check that all
the bolts are tight before riding. Respect the stem type and follow the instruction
below:
1. For Quill Stem: Insert the handlebar stem into the fork steer tube to the
minimum height line that is marked on the side of the handlebar stem. It may
be necessary to loosen the stem Expander Bolt so that the stem can slide
into the fork tube, until you get your desired height of the handlebar stem.
For Threadless Stem: Slide the stem over the fork steer tube.
2. Align the handlebar stem with the front wheel (See Fig. 13). Securely tighten
the stem bolt(s). Note: Some models require a 6mm hex key. (Tightening
torque: 18N.m or 14foot lbs. torque).
3. Positioning the Handlebar:
• Loosen the stem handlebar clamp bolt (Quill) or hex bolts (Threadless).
• Position the handlebar at the desired angle. Make sure the handlebar is
in the center of the stem handlebar clamp.
• Tighten the handlebar clamp bolt (tightening torque: 18N.m or 14-foot lbs.).
4. Be sure that your handlebar and stem assembly is properly tightened before
riding. The handlebar and stem should not rotate in the stem up or down or
in the fork from left or right (Fig. 13).
Pedal Identication:
Fig. 14
12

Step 6: Brake Adjustments
The brakes on your bicycle should be correctly adjusted from the factory.
However, it’s important to check the function of your brakes before your rst ride.
The following instructions are not exhaustive. We strongly suggest you take
your bike to your place of purchase, professional bike shop, or certied e-bike
mechanic for assembly, adjustment, and maintenance.
With the wheels installed, check that both brakes are functioning properly. First
lift the bike and spin the front then the rear wheel to insure they turn freely and
the brake pads are not contacting the brake rotor. If there is some rubbing, you
can adjust the caliper to be inline with the rotor with the following steps:
• First, loosen the caliper xing bolts (do not remove). This will allow the caliper
body to move freely. Now squeezed the brake lever. This will align the caliper
to the rotor via the brake pads. With the brake lever still squeezed, snug the
caliper xing bolts back down. Spin the wheel to conrm there is no rubbing.
• Tighten the caliper xing bolts to 6-8Nm.
• Repeat these steps with the other wheel/brake.
• Next, squeeze the lever to insure both feel rm and are stopping before
they hit the handlebar. If the levers contact the bar or you see uid leaking,
contact Retrospec or you dealer for additional assistance.
The hydraulic brakes are self-adjusting, but will require annual bleeding of the
uid. Retrospec highly recommends this be done by an experience authorized
dealer.
B. Checking Brake Pad Wear, Pad Replacement
Pads that are 1mm thick (or less) need immediate replacement (Fig. 15).
To install new pads, remove the brake caliper from the fork or frame by
unscrewing hex bolts D (Fig. 16). Unscrew (left/counterclockwise), the smaller
hex bolt inside allen bolt B (Fig.17). Lift and pull inner pad downward, using the
protruding tab. Slide thin slot screwdriver under the outer pad and lift up. Hold
the screwdriver in position and remove the pad with a pair of long-nosed pliers.
Fig. 15 Fig. 16 Fig. 17
13

Remove the springs from the worn-out pads and t them onto the new pads.
Replace the new pads, keeping them slightly inclined into the seat of the caliper.
Check that the spring hooks correctly onto the small piston. (When pulling
downwards the pads should not come out). Ret the caliper to the fork (or frame
for rear brake). Turn adjuster screw C (Fig.18) until the pads are centered on the
disc and the wheel spins freely. Again, there may be some noise from the brake
until it “bed” in. You may have to adjust the cable tension and lever adjustment-
follow previous Step A. Brake Lever and its Brake Pad Travel Adjustment.
We strongly advise you have your brakes periodically checked and maintained by
your dealer or a professional bicycle mechanic.
Step 7: Derailleur Gears Maintenance and Adjustment
The gears/derailleur(s) on your bicycle should be correctly adjusted from the
factory. However, as cables do seat and stretch, it’s important to check the
function of your shifting after your rst ride. Note that it’s not unusual for your
shifting system to need some adjustment after being used a few times.
We strongly recommend you have your e-bike serviced by your dealer or
professional bike shop/mechanic.
To ensure long life and eciency for your drivetrain system, it must be kept clean
and properly lubricated. Before attempting any adjustments, make sure you
understand the drivetrain components functions and feel condent to attempt
such maintenance.
• Left shifter controls the front derailleur and chain wheel(s);
Right shifter controls the rear derailleur and rear cogset.
• The largest/larger rear sprockets on the cogset are the low [speed] gears
used for hill climbing and low speed technical riding; the smallest/smaller rear
cogs are for cruising and high(er) speed and downhill riding.
Fig. 18
14

• NOTE: For good shifting and riding experience, follow these 4 actions:
1. Shift only when pedaling (forward), do not shift when stopped.
2. Do not use hard, aggressive pedal pressure while changing gears.
3. Never back pedal when changing gears.
4. Never force the gear shifting levers.
• Rear Derailleur Adjustment:
There are two limit adjustment screws on the rear derailleur - High/”H” and
Low “L”. Looking from the rear of the bike forward, the limit adjustments
center the chain on the high/large and low/small rear cogs which prevents
the chain from going over the large cog and into the wheel/left (the “H” or
high adjustment screw) or into the frame/ right (the “L” or low adjustment
screw).
First, the derailleur cable tension needs to be correct:
Position the shifter(s) so the chain is on the smallest rear cog and largest front
sprocket - check for cable slack at point “B” (Refer to Fig. 19). If there is slack,
loosen the cable nut or hex bolt, pull the cable with pliers and retighten the cable
nut/bolt while pulling cable taut (tightening torque: 5-7N.m or 4-5 lbs.)
High/Large Cog (“H”) Limit Adjustment
Turn the “high limit” adjust screw marked “H” on the rear derailleur so that, again
looking from the rear, the upper guide pulley is below the vertical plane of the
center of the top/large cog.
Low/Small Rear Cog (“L”) Limit Adjustment
Turn the “low limit” adjust screw marked “L” on the rear derailleur so that, again
looking from the rear, the upper guide pulley is below the vertical plane of the
center of the low/small cog.
Small Front Sprocket
Large Front Sprocket
(Front Derailleur)
Chain Guard
Chain Line
Pulleys
Chain
Cable
Tension Roller
Point “B”
Largest Sprocket
Sprocket Cluster
Smallest Rear Sprocket
Largest Rear Sprocket
(Rear Derailleur)
Spoke Protector
Fig. 19
15

1. Operate the shift lever to shift the chain from top gear to 2nd gear.
• If the chain will not move to the 2nd gear, turn the cable adjusting barrel on
the rear derailleur to increase the tension (counterclockwise)
• If the chain moves past the 2nd gear, decrease the tension (clockwise)
2. Next, with the chain on the 2nd gear, increase the inner cable tension while
turning the crank forward. Stop turning the cable adjusting barrel just before
the chain makes noise against the 3rd gear. This completes the adjustment.
Make sure the drivetrain is clean. We suggest “dry” lubricants for most
applications.
Step 8: Check Before Riding
Make sure the wheels are tight and secure. Tighten the front and rear hubs nuts
securely. (Tighten torque: about 30N.m for front wheel, about 25 to 30 Nm. for
rear wheel).
For Quick-Release (QR) hubs/axles, make sure the QR levers are in the locked/
closed position. Before riding, lift the front of the bicycle so that the front wheel
is o the ground, lightly bounce it to the ground and give the top of the tire a few
downward strikes. The wheel should not wobble or come o and there should be
no rattling. Do the same for the rear wheel.
Section ll -
Electrical Components Operation, Maintenance, & Safety
The e-bike in this manual features “Walk Assist”. This electric assistance system
will help riders walk the bike in case of a puncture or other case where the rider
needs to walk the bike.
How start aid works: When pressing the Start Aid button, the bike can be started
at a speed of ~3.5MPH (6km/h). When the bike starts moving forward, start to
pedal and release the “Start Aid” button.
Contents:
• Important Safety Precautions
• Operation
• Battery Installation & Usage
• Display and Functions
• Using and Maintaining the Battery
• Using and Maintaining the Battery Charger
• Using and Maintaining the Electric Hub Motor
• Maintaining the Controller
• Maintaining the Power-o Control of the Brake Lever
• Maintaining the throttle
• Simple troubleshooting
• Main Technical Specication Sheet
16

1. Important Safety Precautions
• We strongly advise wearing an approved helmet which meets local safety
standards.
• Obey local trac rules when riding on public roads.
• Be aware of trac conditions.
• Must be 16 years or older to operate this bicycle.
• Have your bike serviced only by authorized bicycle shops.
• Regular servicing will ensure a better performance and a safe riding
experience.
• Do not place more than 350lbs (159kgs) on the bicycle, which includes the
rider and cargo.
• Never have more than one rider on the bicycle.
• Follow the regular maintenance schedule in this owner’s manual.
• Do not open or attempt maintenance on any electrical components yourself.
• Contact your local bicycle specialist for qualied service when needed.
• Never jump, race, perform stunts, or abuse your bicycle.
• Never ride under the inuence of intoxicating drugs or alcohol.
• Do not ride at night. If riding at night, low-light, or poor weather conditions is
unavoidable, we strongly recommend using front & rear lights, reectors, and
bright, safety clothing.
• Wash with mild soapy water. Dry immediately with a soft, non-abrasive cloth.
• Do not use strong chemicals or abrasives.
WARNING! Do not direct water spray at hubs, bearings, and electrical
components and NEVER use a high-pressure washer—these actions may damage
electrical components and bearings (bottom bracket, hubs, headset).
WARNING! Remove the battery before placing on any type of vehicle mounted
rack for transport.
WARNING! Never y with battery. It is not permitted on passenger aircraft.
2. Operation
Your new electric assistance bicycle is a revolutionary means of transport,
using an aluminum frame, Li-Ion battery, a super high eciency electric hub
motor, and controller with electric pedal assistance system, to support normal
pedaling. These components will ensure safe riding with excellent function and
performance. It’s important for you to note the following guidelines to get the best
possible riding experience.
• Always check your bicycle before riding
• Ensure that the tires are fully inated as indicated on the tire sidewall.
• Remember, performance of the bike and battery range is directly related to
the weight of the rider and baggage/load, together with the stored energy
in the battery. Battery range/performance can vary signicantly based on
terrain, load, & weather conditions.
• Charge overnight, prior to riding the next day.
• Clean and apply chain lube periodically as needed. With a soft rag or towel,
wipe o excess lube. Clean and lubricate half-yearly (minimum).
17

3. Battery Installation & Usage
Retrospec Koa Rev 48V/750W E-bikes have the battery positioned in the down
tube. NOTE: You can pedal one crank revolution to start the motor or by engaging
the throttle, DO NOT ENGAGE THE THROTTLE WHEN YOU ARE NOT READY!
NOTE: Battery Lock (Fig. 1)
From the initial 12 o’clock position (battery and carrier are unlocked), insert the
key into the key slot, press and turn it clockwise to lock the battery into the frame.
Reverse steps to unlock.
Battery Charging
You can charge your battery while installed on the bike or removed for remote
charging. If your bike is near an AC outlet, you can charge it with your bike’s
battery still installed. The charging port is covered by a plastic cap.
Alternatively, you can remove the battery for charging. This feature is useful in
small areas where the bike will not t or AC power supply is not near the bike.
Following the steps above:
• Make sure the battery is unlocked.
• Remember to keep your key secure!
WARNING! Use only the charger provided with the electric bike, otherwise
damage could occur to your battery and void the warranty. When charging, both
battery and charger should be minimum 4 in (10cm) away from the wall, and in a
cool, ventilated environment. Place nothing around the charger while in use!
4. Display and Functions
Dear users, in order to better operate your e-bike, please carefully read the
manual of K5303 LCD display before use.
Fig. 1
18

1. Dimensions
1.1 Material and Color
K5303 product housing is made of black Alloy Aluminum & Tempered glass. The
material of the housing is allowed to be used normally at the temperature of - 40
to 80 , and good mechanical properties can be guaranteed.
2. Function and Button Denition
2.1 Function description
K5303 provides you with a variety of functions and displays to meet your riding
needs. K5303 displays:
• Battery capacity
• Speed (including real-time speed display, maximum speed display and
average speed display)
• Distance (including trip and ODO)
• PAS Level selection
• Backlight turn on
• Headlight turn on / o
• 6KM/H walk assist
• Output Power display
• Error code
• Multiple setting parameters. Such as: wheel diameter, speed limit, battery
capacity setting, various PAS level and power assisted parameter setting,
power on password setting, controller current limit setting, etc.
19