Chirping while engine braking.

sirbike

sirbike

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Joined
Feb 26, 2007
Messages
879
Location
Cleveland OH
Bike
2006 ST1300A
2025 Miles
000259
By rare chance I rode with no helmet or ear plugs to visit a near by neighbor and I discovered this noise. Probably a couple months ago, maybe 3000 miles since since I’ve ridden that way and this noise was not there at that time.
The bike is 2006 with 70,300 miles.
Intermittently there is a chirpity-chirpity-chriping squeaking sound during a narrow range of engine braking. Sounds like it is coming from the middle of the bike down low. Not loud enough to be heard with ear plugs in.
The most consistent way to make the sound is to let the clutch out slowly to precisely engage engine braking just so.
Generally this happens between 50 and 15mph. The sound could be happening above 50 but other sounds maybe drowning it out.
Hot or cold doesn’t matter.

The bike otherwise is absolutely smooth.
Wheel bearings have 10,000 miles on them.
Basically I am figuring that a centrally located item that needs to be loaded at just the right amount to make this sound could be the u-joint.
The rear wheel turns perfectly smoothly.
I hope to do a big ride on this bike in a few weeks. I just bought a 20,000 mile u-joint for $32. Not bad wether I need it now or not.
I can deal with changing the u-joint but definitely prefer not to at this time.
Any thoughts on this?
 
Also, it is heard equally from left and right. Final drive was a thought but it really doesn’t seem to come from that far back.
 
Engine braking can be rough on the engine. You can "chirp" the tires if you down shift and let the clutch out.

How about when you slow down or brake using the brakes only?

Brake pads are relatively cheap.
 
I think it is possible that what you are hearing is a noise from the cam chain tensioners, and that noise is nothing to worry about.

If I correctly understand how the cam chain tensioning system on the 1300 works, it is that system that is responsible for the normal "sewing machine" sound that the 1300 engine sometimes makes. That sound is generated when the engine is developing power (in other words, putting tension on the cam drive system in one direction). I'm going to guess that the new (to you) sound is just a unique sound that the cam chain system makes when tension is applied in the opposite direction (engine braking).

Michael
 
Since you only hear/heard it without the earplugs and the bike doesn't run badly otherwise, I'd say...go ride.
Have a good trip.
 
Thanks, I thought about brake pads.
I am pretty easy on the brakes and mostly I don’t use engine braking as a means of slowing down. Sure during spirited riding, but not generally.
I may better describe this noise as happening during the narrowest range of not quite the lightest load possible of the engine slowing the bike down. Having the engine slowing the bike down just a touch more than just coasting. Or otherwise simply put, just letting off the throttle slightly.
During what is more truly engine braking there is no sound.
Using the brakes or not makes no difference by itself. They only have the effect of changing the load. If I dial in some brake pedal while letting off the throttle just right, I still get the sound.
Say I am going 40mph, I close the throttle, the immediate effect is some level of engine braking, there is no chirping until the bike has coasted to the point that the engine is barely but definitely having a slowing effect.
When I get in the load range that it chirps, the sound goes away immediately upon throttle up or down or pulling the clutch.
 
You have a new sound that wasn't there before so it's cause for concern if not worry. It might be of non-mechanical origins such as an exhaust leak generated only under specific circumstances. Since you didn't hear it the last time you rode under similar conditions it could be something that might get worse.

Are you on the brakes at all when you get the chirp? It seems remote but a pad vibrating in the caliper or on a disc might give a chirp.

It might not be a cause for a whit of concern. But it wasn't there now it is and if you can get rid of it- why not. Good luck!
 
Next time yoh hear it lightly apply your rear brake. I bet it goes away, or at least changes.
 
As per Pete above, get it chirping like a canary then apply brakes front and rear, good luck with that with CBS. Just a light application would rule the brakes out or in.
Then I'd ride with ear plugs.
Upt'North.
 
When you say engine braking are you downshifting? I don't know if the ST has one but if it was a car I would guess throw out bearing.
 
A throw out bearing is located between the clutch fork and the pressure plate fingers. It only operates when the clutch pedal is pressed. A BMW with a dry clutch is the only motorcycle that I can think of that might have one?
 
Thanks for some interesting ideas to mull over and keep in mind.
There is a more or less equivalent of a throw out bearing that the clutch rod bears into. Not likely that what I am hearing could be coming from that. I did have a bad throw out bearing on a 1972 Malibu. It was noisy/rough when the clutch pedal was depressed.
I rode 20miles today, gently accelerating and decelerating the whole way, it chirped/squeaked a couple times.
I’m figure it is serious the sound would be more consistent.
The idea that something not critical is vibrating under just the right condition makes the most sense at this time.
For now the ear plugs are going in, helmet on, and rolling.
 
I have Tinnitus, everything is chirping and squealing and whistling all the time, but I still here well and my 1100 just plays the sweetest sounds I ever heard. I have had heat shield make weird noises like your describing as John Heath has suggested, and exhaust springs, sidestand or centerstand springs. Sounds like maybe your idea of downshifting would be lugging the engine to me, your probably gonna have to put your hands on every little piece and maybe a little light bumping on parts to find a vibration.
 
Have you changed oil brands? Did the noise start afterwards? When I got my ST the previous owner was running Honda non synthetic oil, I switched it over to synthetic motorcycle oil ( Mobil 1) the motor quietened down noticeably.
Just wondered if you maybe changed brands?
 
sirbike said:
By rare chance I rode with no helmet or ear plugs to visit a near by neighbor and I discovered this noise. Probably a couple months ago, maybe 3000 miles since since I’ve ridden that way and this noise was not there at that time.
The bike is 2006 with 70,300 miles.
Intermittently there is a chirpity-chirpity-chriping squeaking sound during a narrow range of engine braking. Sounds like it is coming from the middle of the bike down low. Not loud enough to be heard with ear plugs in.
The most consistent way to make the sound is to let the clutch out slowly to precisely engage engine braking just so.
Generally this happens between 50 and 15mph. The sound could be happening above 50 but other sounds maybe drowning it out.
Hot or cold doesn’t matter.

The bike otherwise is absolutely smooth.
Wheel bearings have 10,000 miles on them.
Basically I am figuring that a centrally located item that needs to be loaded at just the right amount to make this sound could be the u-joint.
The rear wheel turns perfectly smoothly.
I hope to do a big ride on this bike in a few weeks. I just bought a 20,000 mile u-joint for $32. Not bad wether I need it now or not.
I can deal with changing the u-joint but definitely prefer not to at this time.
Any thoughts on this?
Click to expand...

Put the bike on the center stand, put it in gear, and gently roll the wheel both forward and backward and see how far it moves in each direction.
Sometimes a failing U-joint can roll smoothly, and you can easily over look an issue. It may be the U-joint is getting loose enough the roam around a little bit and the chirping your hearing may be it touching the edges when it loads and unloads.
Your rear wheel should not move very far in each direction before getting resistance, if it moves a greater distance, it may be pointing out too much slop in the unit.
And as far as the sound not coming from an area that far back, don't forget the shaft drive is hollow and may throw the sound somewhere else.
Igofar
 
Can you make it chirp while on the center stand? If so, I would suggest you make it chirp and go over the engine w/ a stethoscope. This would probably take two people since it only makes the noise when the engine is winding down.
 
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