occasionally noisy valve clatter? ( probably overreacting)

[Jharpphoto]

Afternoon gentlemen,  I've noticed on occasion when I am in the wrong gear and accelerating (3rd gear rather than 2nd gear) that I will hear a little (what I believe to be) valve rattle/clatter).  When I am shifting as God intended at the upper end of the RPM range 4500-5000ish RPMs the only sound I hear is that beautiful boxer engine and a thousand angels singing!  Is the valve noise I hear normal under the circumstances I described (under RPM'd)?  I'm sure I'm being over sensitive but, but looking for your feedback. Forgot to mention the bike is a 2013 RT w/ 18,000 miles on the clock.  Thanks in advance for any direction etc.

[dirtrider]

1 hour ago, Jharpphoto said:

Afternoon gentlemen,  I've noticed on occasion when I am in the wrong gear and accelerating (3rd gear rather than 2nd gear) that I will hear a little (what I believe to be) valve rattle/clatter).  When I am shifting as God intended at the upper end of the RPM range 4500-5000ish RPMs the only sound I hear is that beautiful boxer engine and a thousand angels singing!  Is the valve noise I hear normal under the circumstances I described (under RPM'd)?  I'm sure I'm being over sensitive but, but looking for your feedback. Forgot to mention the bike is a 2013 RT w/ 18,000 miles on the clock.  Thanks in advance for any direction etc.

Afternoon Jharpphoto

 

That seems like an odd riding circumstance for valve noise without also having the same valve noise at idle.

 

Are you sure that it isn't a light spark knock on hard acceleration  (commonly called pinging)?

[Jharpphoto]

2 minutes ago, dirtrider said:

Afternoon Jharpphoto

 

That seems like an odd riding circumstance for valve noise without also having the same valve noise at idle.

 

Are you sure that it isn't a light spark knock on hard acceleration  (commonly called pinging)?

I definitely don’t have noise at idle. I’m not familiar with “ light spark knock” . What is that exactly?

[John Ranalletta]

16 minutes ago, dirtrider said:

Afternoon Jharpphoto

 

That seems like an odd riding circumstance for valve noise without also having the same valve noise at idle.

 

Are you sure that it isn't a light spark knock on hard acceleration  (commonly called pinging)?

DR,

 

Might the clatter be the fuel injectors?  Just askin'.

 

 

[Jharpphoto]

Just read up a bit on spark knock. Not sure if that’s what I’m hearing either ( could be).  Now I’m a little concerned. I hoped I was simply shifting poorly, causing that occasional noise. Any suggestions on how I could narrow down the possibilities?

[Hosstage]

It sounds like you may be lugging the engine, causing pre-detonation. The way to avoid this is to ride correctly in the right gear. Don't lug the motor, don't accelerate aggressively when in the lower range of a gear, keep the motor working in its happy spot. Nothing to worry about if you don't chug the motor.

What is the octane rating of the fuel you're using? That may have an effect.

 

[dirtrider]

16 hours ago, Jharpphoto said:

Just read up a bit on spark knock. Not sure if that’s what I’m hearing either ( could be).  Now I’m a little concerned. I hoped I was simply shifting poorly, causing that occasional noise. Any suggestions on how I could narrow down the possibilities?

Morning  Jharpphoto

 

Probably the best way to narrow it down is to have a qualified BMW tec take it for a ride. Or at least listen to it when the noise is present. 

 

You can possibly try a few things, like running most of the present gasoline out of your fuel tank then re-filling it with the highest octane gasoline you can find from a top tier company.

 

Another thing that m-i-g-h-t help identify the noise is next time it happens just throttle up until you hear the noise then back off the throttle slightly to see if the noise goes away.  If you can get the noise to come & go as you throttle up then slightly back off on the throttle then that more points to a little spark knock not valve noise.

 

If using the highest octane (top tier) gasoline you can find helps reduce or remove the noise then you are probably dealing with a little spark knock. 

 

A little light spark knock on heavy throttle at lower RPM's at heavy engine load doesn't hurt much as it is temporary, short lived, & typically not destructive.  

 

Spark knock (ping) happens after the spark occurs & the cylinder fires so it is mainly a type of combustion knock. 

 

The damaging one is pre-ignition, that is when the fuel/air mixture in the cylinder actually self-ignites before the spark occurs. This typically happens as the piston is well before TDC so it can really cause damage. In a lot of cases you can't hear this one as it typically happens at high speeds, high engine load.

 

When did you start noticing the noise? If it just started happening then possibly you just got a tank full of low octane gasoline, or got a tank of early winter blend gasoline. 

 

If it has been happening for while  throughout a number of fuel fill-up's then it should probably be looked into & identified if possible.

 

You can also keep an eye on your spark plugs, if you have a serious combustion problem like pre-ignition then damage will usually show up on the spark plugs first. 

 

 IF, your noise is combustion related then it does sound more like a burst type spark knock (ping) than a damaging pre-ignition condition.   

 

 

 

 

 

 

 

[Jharpphoto]

thanks everyone. I'll keep an eye on this but am hoping it is due to me lugging the engine. I appreciate all the suggestions and insight.

[Alan in BC]

Could this be a bit of cam chain noise?  I notice that I get a slight rattle (2013) when the tach needle swings past 3500 or so.  I have always wondered what it might be.