The Very Strange Noises FAQ

by Kristian #562 (20/10/01)
Please read the Disclaimer before attempting any work in this FAQ.
Last Updated: 18 Feb 2007, by Winter #1935

For other helpful FAQs:

My Bike seems to make a Strange Noise. How can I fix it?

There a number of common sources of Noise on the F650. If you're looking for Vibrations see this FAQ.

Do you have a short list to guide me in the right direction?

The table below should help guide you to your noise. However if you can not find it based on the table, read through all the noises.

Keywords Perceived Location Other Attributes Which Noise?

"Front" Noises (Instruments, Forks, Battery)
Clicking mid-lower forks   Noise 1
Clicking (turning steering)   Noise 2
Buzzing or Rattling Front Can be rev dependant
Not an engine noise
Noise 5
Noise 7
Noise 12
Noise 13
Noise 15
clunk clunk clunk Front End   Noise 18
Rattle up front Under certain load / vibration conditions
Lowering kit
Noise 19
Buzzing / several rapid clicks / rythmic clicking Fairing/Speedo Area/instrument panel   Noise 21
Noise 27
Noise 52
buzzing Front Stops when starter depressed
Stops when heated grips turned on
Headlight dims
Noise 33
metal ball (rolling) in a cup under the speedometer
top of the fork
30 to 35 mph
in gear or with the clutch in
Noise 38
rattle headlight / steering head heard when riding over expansion joints or small potholes Noise 40
keyboard clicking/clacking
small plastic object shaken gently inside 35mm film canister
instrument cluster/ windshield beween 30-50 mph Noise 44
metalic rattle front off-road, downhill Noise 49
ruler twanging on desk edge front can be rev dependant
possibly temperature dependant
mainly 2nd / 3rd gear
Noise 50
tick-tick-tick pause front / instruments after turning bike off
can last for several minutes
tach / speedo needle "twitches"
Noise 51

Engine / Transmission Noises
Rattling From engine At idle Noise 3
Plink Plink Engine Trailing throttle / blip at idle Noise 6
Farting and a loud popping Front (not backfiring) Noise 9
Popping   When Shifting, mainly 3rd to 4th Noise 17
Rattle ("jingling" keys) Transmission While moving Noise 20
Bizzar buzzing Engine somewhere Rear wheel not spinning in gear Noise 56
metallic rattle Engine 2500-3500 in 3rd upwards
hard the noise reduces
Noise 22
Knocking   Gets Faster as Idle Raised
when in neutral, clutch engaged
Noise 24
loud knock Engine doesn't go away off-idle Noise 25
scraping Engine When engine cold
Once per second
Noise 29
tick-tick-tick-tick Engine drowned out @ 3000rpm Noise 30
Khat-Khat-Khat LHS Engine / Engine When engine cold Noise 34
Noise 54
engine knock, chain rattle, keys in the cylinder   4200-4500 RPMs in 4th and 5th gear
occaisionally when I decelerate
more noise after warming up
Noise 35
increasingly loud Engine Around 3000kms
mic the cylinder bore (out of spec)
Noise 37
something releasing tension / big CLICK From the starter? Sometimes when turning off Noise 42
lightning storm cylinder At very low rpm
On start-up without enough choke
Noise 43
grinding noise Transmission starting in 1st gear with a bit of a load
and starting up a slope.
Noise 53
(GS) rattle transmission While on sidestand
Goes away when clutch pulled in
Noise 55

"Rear" Noises
Rattling Chain area   Noise 11
Rattle LHS Rear   Noise 14
Noise 16
gargle sound exhaust after downshifting (after clutch release)
rapid acceleration or rapid deceleration
Noise 23
plastic rattle rear / exhaust   Noise 36

Other Noises
Squeal Brakes   Noise 4
Tic Tic Tic Solenoid, near battery   Noise 8
weird "wooo" When compressing rear shock   Noise 10
humming / feline purring   Under load
Lower rpms, upward slopes
"on" for half a second, "off" for another half second
Noise 26
scraping / dragging   Factory lowered model
Under heavy load
Noise 31
crunch crunch   Under load @ low rpm Noise 32
loud grinding squeal engine starting after stalled
shifting down coming to stop
Noise 39
playing card clothespinned to my wheel
knocking sounds from bottom end
right side slows down as I slow down Noise 41
sporadic grating the tranny on the RHS lasting for a few minutes
follows engine RPMs
more at lower speeds
Sometimes gets 3x loud for 10 seconds then subsides
Noise 45
noise engine engine from idle to about 2000rpm
after 2000rpm it fades to normal piston noise
replaced cam chain tensioner, noise reduced
Noise 46
moderately-pitched (MP) clunk valve/cylinder area when turning off bike (engine running) Noise 47
Whirring of gears (hum)   persistent but inconsistent Noise 48
something electromechanical shutting off /
electrical antenna going down
injector's area   Noise 27
Noise 28

So what does it sound like and where does it come from?

For Engine Noises: To help you identify WHERE it is coming from, grab a good solid screwdriver, put the tip on the Engine where you THINK the noise is coming from and the handle against your ear, like stethoscope. Move the tip around until you determine the source location.

Other Comments / Hints

These are some of the questions you might get asked, or some of the things to think about to identify and fix the noise:

A knock? Mmmmm......need some more description. Is it a deep knock, like clonk...clonk etc, OR is more of a tap....tap? What side of the engine? and is it up the top OR lower down on the motor? When did this noise start? Slowly over time......after you did something with the bike, like after a mad 3 day desert race :-) Has it ever run low on oil.......some prior history may help the diagnosis.

  • IF its lower down and a heavy clonk noise.....then look for a sad big end bearing.......these can make a very terminal sounding noise at low revs with open throttle (loaded engine)
  • If it higher up in the middle of the motor with not so much of a heavy could be piston slap (loose piston to bore clearance)
  • If is more of a rattle then look at the cam chain tensioner setup. IT MAY also be a balancer shaft problem too. I would start with doing an oil pressure check with a master gauge......that is, remove the pressure sensor and connect a separate mechanics test pressure gauge. Run the bike on road and make sure that pressures are in spec. Next........drain the oil and check for metal pieces on the drain plug and also metallic sparkle in the oil itself, wash the oil filter out in clean petrol and look for residue from the filter. Remove the cam cover and check the chain for slack, look down inside to see if you can see any wear/broken cam chain guides etc.

Jack, F650GS, Australia.

Other things to try / consider:

What Should I Mention in the Forums?

If you can not find your noise or a similar noise in the list, and the other suggestions do not help identify the noise... ask in the Forums. When you do, provide the following information:

  1. What model / year bike do you have? (Most people forget to tell us this) Is it a Classic, GS, Dakar, CS and what year was it made in? Also tell us if it has ABS - this could help the diagnosis.
  2. What does it sound like? Does it sound metalic, or like plastic? Is it a deep knock like a clonk clock or more of a tap tap? Is it a heavy clonk clonk or a lighter plink plink?
  3. Where does it sound like it is coming from? Is it coming from the engine? Left or right side? Front forks? Rear of the bike? If you can safely get off the bike to hear the sound, where does it come from? Have you tried the mechanics stethoscope? Where abouts in the engine is it coming from?
  4. When did it start? So when did the noise start? Has it been gradual or did it start suddenly? Did it start after a long trip? Have you done any maintenance lately? Have you heard it before?
  5. Under what conditions does it occur? Tell us more about when you hear the noise:
    1. Temperature? Does it happen only when the bike is cold, or when it is hot? Does the noise change with the ambient / air temperature?
    2. Engine Speed or Bike Speed? Does it only happen between certain engine speeds (eg between 3500rpm and 4500rpm), or does it occur only at certain road speeds (eg below 30mph / 50kph).
    3. In all gears, Neutral, clutch engaged? Does it only occur when in neutral? etc (Note: Just because you can not hear it in 5th gear does not mean it is there when you are in 5th gear)
    4. Frequency? Does it happen when you turn the key on / off? Does it happen just after you start the bike? Does it happen once a minute, once a second?
    5. Load? Does it occur under heavy load, or is it just under a normal load?
    6. Road Conditions? On road or off road? Uphill, downhill?
  6. Anything else? Is there anything else you think might help identify the noise?

But please, please, please - DON'T FORGET to tell us how you fixed the problem. Because then you help others.

Send some more Noises...

You know the hardest thing about working on the Noises FAQ?
You spend the next 1000kms listening for every little tick, clonk and thunk!