Repair / Idle and running
Idle and running
Problems, repairs and parts for the idle and running.
Problems
- Bogs down or chokes at full throttleRide with care
- Cuts out when riding over bumpsRide with care
- Cuts out randomly, then restartsRide with care
- Misfires or dies in heavy rainRide with care
- Engine dies when the side stand moves or the bike is put in gearRide with care
- Flat spot in the middle of the rev rangeOK to ride
- Revs hang or drop slowly after closing the throttleRide with care
- Hesitates or stumbles when opening the throttleRide with care
- Idle speed is too highRide with care
- Idle speed rises and falls on its ownRide with care
- Misfires or stutters when accelerating hard or climbingRide with care
- Rough, lumpy or uneven idleRide with care
- Engine runs hot and lean, pops and pinksRide with care
- Engine runs rich, smells of fuel and smokes blackRide with care
- Engine stalls at idle or at junctionsRide with care
- Engine stalls once it is fully warmRide with care
- Surges or jerks at steady cruising speedRide with care
- Misfire: ignition or fuel?Ride with care
Repairs
- Adjust carburettor idle speed and mixtureHome workshop · 20 to 40 min
- Clean or replace the air filterRider job · 15 to 40 min (estimate, plus drying time for foam)
- Remove, check, gap and fit a spark plugRider job · 15 to 20 min
- Find an intake air leakHome workshop · 20 to 45 min
- Clean the carburettorHome workshop · 1.5 to 3 h
- Read engine fault codes (fuel injection)Home workshop · 15 to 30 min
- Clean the throttle bodyHome workshop · 30 to 60 min
- Reset the idle after throttle body workWorkshop job · 15 to 45 min at a workshop with the right tool
- Check and adjust valve clearanceHome workshop · 45 to 90 min (estimate, screw-and-locknut type)
- Test engine compressionHome workshop · 30 to 45 min
- Check for a spark safelyHome workshop · 10 to 15 min
- Test the ignition coil and plug capHome workshop · 30 to 60 min (fuel tank may need removing)
- Check the carburettor float and needle valveHome workshop · 30 to 60 min with the carburettor off
- Check the engine sensors (TPS, MAP, temperature)Workshop job · 10 min for home checks; 30 to 90 min at a workshop
- Check air cooling (fins, airflow, mixture)Rider job · 20 to 40 min
- Adjust throttle free playRider job · 10 min
- Check the choke or starter valveHome workshop · 20 to 45 min
- Assess bottom end and internal engine damageWorkshop job · 1 h assessment; strip 4 to 10 h
- Lubricate or replace the throttle cableHome workshop · 30 to 60 min
- Check the oxygen sensorWorkshop job · 10 min for home checks; 30 to 60 min at a workshop
- Read a spark plugHome workshop · 10 to 15 min, plus a short ride
- Road test to diagnose a faultRider job · 15 to 30 min
- Check the fuel tap, lines and flowHome workshop · 20 to 45 min
- Replace the fuel filterHome workshop · 20 to 40 min for an inline filter; in-tank filters are workshop jobs
- Check the fuel tank ventRider job · 10 to 20 min
- Check the fuel pump (fuel injection)Home workshop · 15 to 45 min for the home checks
- Check the fuel injectorWorkshop job · 10 min for home checks; 1 to 2 h at a workshop
- Drain old or contaminated fuelHome workshop · 30 to 60 min
- Find and fix an exhaust leakHome workshop · 30 to 60 min
- Decarbonise a two-stroke exhaust and portWorkshop job · 2 to 4 h
- Clean and tighten battery terminalsRider job · 15 to 30 min
- Check fuses and relaysRider job · 10 to 30 min
- Test the engine stop switchHome workshop · 20 to 30 min
- Test the side stand, clutch and neutral switchesHome workshop · 20 to 40 min
- Test the ignition switchHome workshop · 20 to 40 min
- Clean and seal electrical connectorsHome workshop · 15 to 45 min
- Clean and tighten earth connectionsHome workshop · 20 to 45 min
- Find a wiring faultHome workshop · 30 to 90 min
- Test and charge a 12 V batteryHome workshop · 15 min to test; charging takes many hours
- Test the charging systemHome workshop · 20 to 30 min
- Check the side standRider job · 10 to 20 min
- Test the neutral switchHome workshop · 20 to 45 min
- Adjust clutch lever free playRider job · 10 to 15 min
- Measure fuel consumptionRider job · 2 to 3 tanks of normal riding
- Check and adjust chain slackRider job · 20 to 30 min
- Check the cush drive rubbersHome workshop · 30 to 60 min
- Clean and lubricate the fuel capRider job · 10 to 20 min
