Sears
Cycling

Model # 502457221 Official Sears 20" moto-cross bicycle

Here are the diagrams and repair parts for Official Sears 502457221 20" moto-cross bicycle, as well as links to manuals and error code tables, if available.

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Model diagram and schematic

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Showing 10 of 69 parts  |

Axle Mx 303520

#NI

All parts diagram

Axle mx

Part #303520

The manufacturer no longer makes this part, and there's no substitute part

R Wheel Assy 303013C
#18

Unit parts diagram

R wheel assy

Part #303013C

The manufacturer no longer makes this part, and there's no substitute part

Spk 7-9/16 303155
#8

Unit parts diagram

Spk 7-9/16

Part #303155

The manufacturer no longer makes this part, and there's no substitute part

Hngr Lck Nut 8512Z
#1

Crank hanger bearing set diagram

Hngr lck nut

Part #8512Z

The manufacturer no longer makes this part, and there's no substitute part

Bicycle Axle Nut And Washer 303160
#1

Bendix coaster brake diagram

Bicycle axle nut and washer

Part #303160

The manufacturer no longer makes this part, and there's no substitute part

Cone 10282
#4

Crank hanger bearing set diagram

Cone

Part #10282

The manufacturer no longer makes this part, and there's no substitute part

Bearing 304662
#7

Bendix coaster brake diagram

Bearing

Part #304662

The manufacturer no longer makes this part, and there's no substitute part

Grip 32770
#2

Unit parts diagram

Grip

Part #32770

The manufacturer no longer makes this part, and there's no substitute part

Bearing Set 303384
#7

Head bearing set diagram

Bearing set

Part #303384

The manufacturer no longer makes this part, and there's no substitute part

Owner's Manual F-4060
#28

Unit parts diagram

Owner's manual

Part #F-4060

The manufacturer no longer makes this part, and there's no substitute part

Symptoms for gas walk-behind mowers

Choose a symptom to see related walk-behind mower repairs.

Main causes: dirty carburetor, bad spark plug, clogged air filter, engine choke problems, clogged gas cap vent…

Main causes: stale gas, engine needs tune up, bad spark plug, dead battery, bad recoil starter, faulty safety switch, ba…

Main causes: uneven wheel height settings, damaged wheel, dull or damaged cutting blade…

Main causes: drive control cable failure, worn or broken drive belt, bad transmission, broken drive wheel…

Main causes: engine needs tune up, dirty or clogged carburetor, damaged flywheel key…

Main causes: damaged cutting blade, loose cutting blade, damaged flywheel key, engine needs tune up…

Repair guides for gas walk-behind mowers

These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.

How to rebuild a lawn mower carburetor

How to rebuild a lawn mower carburetor

The carburetor mixes air with fuel to drive the piston. Rebuild the carburetor if it's clogged or leaks.…

Repair difficulty
Time required
 60 minutes or less
How to replace a lawn mower recoil starter on an OHV engine

How to replace a lawn mower recoil starter on an OHV engine

Replace the recoil starter if it doesn't move when you pull the starter rope.…

Repair difficulty
Time required
 15 minutes or less
How to replace a lawn mower wheel

How to replace a lawn mower wheel

Learn how replace a damaged wheel on a walk-behind lawn mower—it's a quick, easy fix.…

Repair difficulty
Time required
 15 minutes or less

Articles and videos for gas walk-behind mowers

Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.

How to enjoy all the online benefits we offer on our Sears PartsDirect website

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

Lawn mower won't start troubleshooting video: can't pull recoil pull cord

Lawn mower won't start troubleshooting video: can't pull recoil pull cord

A blade obstruction, bad recoil starter or locked-up engine can prevent the pull cord on your mower from working. See ho…