Fault Symptoms

The information here is intended as a guide to speed up resolution of problems. There are a number of common fault symptoms on the 650GS, while some faults can have multiple causes, the most likely cause is shown.

It is not a large list at the moment but it will be updated and expanded over time.

Known Causes
Excessive pulsing in ABS
Air in the brake lines
Rear brake not releasing
Brake Line breaking up internally
Instability at high speed
Check rear wheel alignment and rear tyre beading
Dead Dash
Dirt on Circuit board, voltage regulator shutting down
ODO/Clock digits cycling
Dirt on circuit board or capacitor faulty
Dash intermitent or not start immediately
Poor tension on 12 pin socket retaining clip
Speedo/Tacho odd readings
On dual spark caused by non resistive spark plug
Speedo readings high or low
Faulty rear wheel sender/cabling or poor adjustment
Dash Lamp and Indicators flashing dimly
Leakage to earth in indicator switch (replace grease)
Neutral dash lamp lights dimly
Neutral switch earth leakage / pinched wire / dirt build up
Oil pressure dash lamp lights dimly at idle
Dirt in the pressure sender oil pathways, clean it
Engine wont turn off with key
Wire chafing or faulty diodes in 4 way flasher circuit
Engine starts, runs, dies on acceleration
Broken wire to Throttle Position Sensor
F650GS Single Spark surging and stalling
Early firmware and/or wrong Fuel Injector
Exhaust glows at idle
Faulty Idle Actuator (may also be the O2 sensor)
Excess oil in air box
Piston rings or broken lands between the rings
Uneven idle and rough running
Check electrical connections/Idle Acuator/TPS/O2 sensor
Sticky clutch, hard to select neutral or first gear
Uneven clutch release, update clutch release head
Cant select gears or hard to select
Bent neutral switch pin or broken switch
Loss of Fuel Pressure
Broken fuel pump power wire in fuel tank
Epoxy bits in oil at oil change
Check Alternator Stator for overheating
Stalling when slowing down
Check speed sensor gap/Idle Actuator/TPS
Fan does not Operate
Failure of BMSC Fan Output Stage
Engine cuts out when opening throttle
Broken wire on Throttle Position Sensor
General Problems
Fuel Leak when on Side Stand
Faulty Fuel Pump retaining ring or tank pressurisation
Starting Problems
All models - Will not Start
Check side stand/clutch/Neutral switch lockout circuits
Check crank sensor for metal particles
Dual Spark (USA) - Will not start
Check Fuel Tank Vent Valve Connections
Dual Spark hard starting
Firmware prior to 210E and early decompression lever
Hard Starting, hot or cold
Check exhaust valve clearances / decompression lever
650X/G650GS/Sertao Hot Start Problems
Replace Decompression Lever - TSB 1100312-015