| Problem |
Description |
Solution |
| Engine won’t start |
No noise or crank when pressing the starter button. |
Check battery voltage, ignition switch, kill switch, starter relay, and fuses. |
| Engine cranks but won’t start |
Engine turns over but fails to fire. |
Check spark plug, fuel supply, clean fuel injectors/carburetor, check compression. |
| No spark |
No ignition at plug during cranking. |
Test ignition coil, CDI, stator, spark plug, and wiring harness. |
| Weak or inconsistent spark |
Spark is faint or inconsistent. |
Replace spark plug, inspect coil, test CDI, check for corroded connections. |
| Hard to start (hot or cold) |
Engine takes multiple tries to start, regardless of temperature. |
Clean throttle body or carb, check fuel quality, inspect choke/enricher. |
| Engine starts then stalls |
Runs briefly then cuts off. |
Check fuel pump (if EFI), clean idle circuit or IAC valve, inspect fuel lines. |
| Rough idle |
Engine idles erratically or surges. |
Adjust idle speed, clean throttle body, inspect intake boots for air leaks. |
| Hesitation or poor acceleration |
Sluggish throttle response or bogs down. |
Clean or replace air filter, clean injectors/carb, inspect throttle position sensor. |
| Backfiring |
Popping from intake or exhaust on throttle changes or decel. |
Adjust air/fuel mixture, inspect exhaust and intake for leaks, check timing. |
| Overheating |
Engine gets hot quickly or fan never activates. |
Inspect cooling fan, coolant level, radiator, thermostat, and temp sensor. |
| Excessive exhaust smoke |
Blue = oil burn, black = fuel-rich, white = coolant or steam. |
Blue: valve seals/piston rings. Black: rich mix. White: blown head gasket. |
| Clutch slipping (CVT system) |
Engine revs high, but wheels respond poorly. |
Replace worn belt, inspect and clean clutch sheaves, check belt tension. |
| Transmission hard to shift |
Trouble shifting into or between gears. |
Check shift linkage, clutch operation, fluid level, inspect CVT system. |
| Grinding noise while shifting |
Loud grinding/clunk when changing gears. |
Check idle speed, clutch engagement, and transmission internals. |
| Battery not charging |
Battery drains quickly during or after riding. |
Test stator, regulator/rectifier, and battery health. |
| Starter doesn’t engage |
No click or movement from starter motor. |
Test solenoid, starter motor, battery voltage, and connections. |
| Electronics not functioning |
Dash, lights, or fan not working. |
Inspect fuses, relays, ground wires, and harness for damage or corrosion. |
| 4WD system not engaging |
4WD switch doesn’t activate front diff. |
Test actuator motor, inspect switch and wiring, verify voltage to actuator. |
| Fuel leak |
Smell of gas or visible fuel on engine or ground. |
Check fuel lines, clamps, tank, fuel pump seal, and connections. |
| Weak or soft brakes |
Brake pedal/lever feels spongy or ineffective. |
Bleed brake lines, inspect pads, replace old fluid, check master cylinder. |
| Squealing or noisy brakes |
High-pitched noise while braking. |
Replace worn pads, clean rotors, check for debris or warped components. |
| Excessive vibration while riding |
Unusual shaking from engine or chassis. |
Inspect engine mounts, driveshafts, CV joints, and wheels. |
| Steering pulls to one side |
ATV veers when driving straight. |
Check tire pressure, wheel alignment, steering linkage, and front suspension. |
| Suspension feels harsh or squeaky |
Stiff or noisy ride, especially over bumps. |
Grease suspension pivots, inspect shocks, replace worn bushings. |
| Fan not turning on |
Engine overheats and fan doesn’t engage. |
Test fan motor, thermal switch, relay, and wiring connections. |
| Speedometer or odometer not working |
No reading or incorrect readings on dash. |
Check speed sensor, wiring, and display unit. |
