| Problem |
Description |
Solution |
| Engine won’t start |
No response or sound when pressing start button. |
Check battery, starter relay, kill switch, ignition switch, and fuses. |
| Engine cranks but doesn’t start |
Engine turns over, but does not ignite. |
Check for spark, fuel flow, clean carburetors, inspect choke, check compression. |
| No spark |
Spark plug does not fire. |
Test ignition coil, CDI unit, stator, and inspect wiring connections. |
| Weak or inconsistent spark |
Spark is faint or intermittent. |
Replace spark plug, test ignition components, ensure proper grounding. |
| Hard to start (cold or hot) |
Requires repeated attempts to start, with or without throttle. |
Clean/rebuild carbs, check choke system, inspect fuel quality and lines. |
| Engine stalls shortly after start |
Engine starts, runs briefly, then shuts off. |
Clean idle jet, adjust idle speed, check fuel valve and venting. |
| Rough idle |
Engine idles unevenly or surges at idle. |
Adjust idle screws, clean pilot circuits in carbs, inspect vacuum lines. |
| Poor acceleration / low power |
Sluggish throttle response or lack of top-end speed. |
Clean air filter, inspect throttle cables, clean and sync carburetors. |
| Backfiring (intake or exhaust) |
Popping sound from exhaust or carburetor. |
Check for air leaks, adjust fuel mixture, inspect exhaust joints. |
| Overheating |
Engine gets excessively hot, possible fan not working. |
Check cooling fan, radiator, thermostat, coolant level, and oil level. |
| Excessive smoke from exhaust |
Blue = oil, black = fuel-rich, white = coolant. |
Blue: Rings/valves. Black: Tune carbs. White: Head gasket or coolant leak. |
| Clutch slipping |
Engine revs high but ATV doesn’t move properly. |
Inspect and replace worn drive belt, check clutch sheaves. |
| Transmission won’t shift smoothly |
Gears feel sticky or won’t engage easily. |
Inspect shift linkage, change gear oil, check belt and pulley alignment. |
| Grinding noise when shifting |
Unusual noise during gear engagement. |
Check belt deflection, clutch wear, and transmission components. |
| Battery drains quickly |
Battery goes flat even while riding. |
Check stator output, regulator/rectifier, and battery condition. |
| Starter doesn’t turn or slow crank |
Starter is weak or silent. |
Inspect starter motor, solenoid, battery voltage, and ground connections. |
| Electrical accessories not working |
Lights, fan, dash, or indicators malfunction. |
Inspect fuses, switches, wiring harness, and connectors. |
| 4WD system not engaging |
4WD button/switch doesn’t activate front differential. |
Test actuator motor, 4WD switch, and wiring; inspect front diff engagement. |
| Fuel leaking |
Gas smell or drips near carb or tank. |
Inspect fuel hoses, petcock, carb bowl gasket, tighten clamps. |
| Spongy or weak brakes |
Brake pedal or lever feels soft, poor stopping power. |
Bleed brakes, check pads/shoes, inspect master cylinder and fluid level. |
| Vibration or rattling noise |
Excessive vibration through handlebars or frame. |
Check engine mounts, U-joints, tires, and loose bolts or brackets. |
| Steering pulls to one side |
ATV veers left or right on straight terrain. |
Check tire pressure, alignment, brakes, and suspension components. |
| Suspension feels harsh or noisy |
Stiff ride or squeaking over bumps. |
Grease suspension arms, inspect shocks and bushings, replace if worn. |
| CVT belt wear/slipping |
Poor throttle response or high RPMs with little movement. |
Replace worn CVT belt, inspect clutches, clean sheaves and vents. |
| Fan not turning on |
Engine overheats, fan doesn’t activate. |
Test fan motor, temperature sensor/switch, and related wiring. |
