Tapping noise at exhaust pipe.

[MoldTheClay]

https://youtu.be/tJam_JTqvyo

I am taking my 2012 Ninja 1000 in tonight to Motoguild to start tearing down for my valve job tomorrow. My valves are overdue for an adjustment and i felt some possible performance issues in my bottom end, but everything sounded mostly normal. Last night i thought i might have heard some more noise from the exhaust end of my engine but it sounded fine at the pipes.

Now on my lunch break i heard the tapping noise that i recorded in that video.

Just one of my exhaust valves finally far enough out of spec to start making noise, or should there be other things that i need to look into while I am in there?

Only other thing that came to mind is something with my exhaust itself?

 

[bobl]

Sounds more like the cam chain to me. If you're doing the valve adjustment, you will probably have to remove the cam chain tensioner anyway, so good time to inspect and re-assemble it. Before you remove the tensioner, remove the valve cover and inspect the amount of slack in the cam chain.

 

[GPzPop]

but occasionally the header can crack / break off right at the flange, but this would sound more like an exhaust leak along with the rattle

 

[Busy Little Shop]

To troubleshoot an internal noise the first step is to establish the
rate at which it occurs... is the noise in time with the camshaft or
crankshaft??? camshafts rotate 1/2 the speed of the crankshaft...
possible source of camshaft speed noises are shim and bucket
clearances... loose cam bearing blocks... broken valve springs...
possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings...

 

[EastBayDave]

common source of "tapping noise" at the exhaust flange is a bad pipe gasket where it meets the head. Cheap & easy fix. Some might try tightening the flange nuts slightly BUT DO NOT exceed the torque spec or you might strip the threaded head stud.

The exhaust gaskets are cheap, & easy to replace. I'd just replace them to exclude them as a source of the noise...? :afm199

 

[MoldTheClay]

Ordering exhaust gaskets just because why not. This bike is old enough that it can only be a good idea. I should be cracking into the head cover today or tomorrow and can check the condition of my chain and tensioner. I looked at me headers yesterday while i was at motoguild and saw some dirt and grit in the area around my #1 header, so it is likely that is the source.

Really hoping i can get that off without taking off the radiator though!

Any problems with continuing to run the bike with a leaky header if i get my valves done before i can get my gaskets? I know performance will take a hit from an exhaust leak but anything else?

Edit: my headers not "me headers" but dont want to edit out my unintentional pirate speak. Arrrr.

 

[Maddevill]

If you have an exhaust gasket leak you will hear it at the head pipe, not at the exhaust. You can run your hand around the head pipe connection. If it's a bad enough leak you can feel the air pulses.

Mad

 

[Sharky]

To troubleshoot an internal noise the first step is to establish the
rate at which it occurs... is the noise in time with the camshaft or
crankshaft??? camshafts rotate 1/2 the speed of the crankshaft...
possible source of camshaft speed noises are shim and bucket
clearances... loose cam bearing blocks... broken valve springs...
possible source of crankshaft speed noises are a scuffed piston...
stuck piston ring... rod bearings...

When Busy Little Shop gives advice....

 

[RVFRick]

When Busy Little Shop gives advice....

Wealth of motorcycle information, is he. Hmmmmmm.

 

[MoldTheClay]

imgur.com/gallery/7L1Lv9n

Okie-dokey, thought the noise went away with my valve adjustment, but it is back. It is most noticeable at the exhaust end but I am thinking that is because the noise of the engine drowns it out on the front end. I kinda hear the tap when I am up close to the left side of the engine around exhaust header 1. I noticed a weird low pulsing noise when idling after getting home from my commute and of course that pipe noise is back again. I thought it went away with my valve adjustment but now the noise is back just like before.

One of the bolts coming out of my header looks really gunked up and corroded with what looks like a black mark where the header connects. Guess I found the source?

 

[EastBayDave]

imgur.com/gallery/7L1Lv9n

Okie-dokey, thought the noise went away with my valve adjustment, but it is back. It is most noticeable at the exhaust end but I am thinking that is because the noise of the engine drowns it out on the front end. I kinda hear the tap when I am up close to the left side of the engine around exhaust header 1. I noticed a weird low pulsing noise when idling after getting home from my commute and of course that pipe noise is back again. I thought it went away with my valve adjustment but now the noise is back just like before.

One of the bolts coming out of my header looks really gunked up and corroded with what looks like a black mark where the header connects. Guess I found the source?

I wouldn't worry about that "gunked-up" head stud for now. Fix the leak 1st.

I'd run down to your nearest (EBM?) & buy a set of 4 exhaust gaskets. They are cheap & easy to replace. Look at the link below for part number #11060.

https://www.ronayers.com/oemparts/a/kaw/500b9043f8700223e479a1bc/muffler-s

 

[stangmx13]

engines are noisy. I don't think u have a problem.

 

[ctwo]

Maybe that gunk is carbon build-up from the leak?

 

[MoldTheClay]

I wouldn't worry about that "gunked-up" head stud for now. Fix the leak 1st.

I'd run down to your nearest (EBM?) & buy a set of 4 exhaust gaskets. They are cheap & easy to replace. Look at the link below for part number #11060.

https://www.ronayers.com/oemparts/a/kaw/500b9043f8700223e479a1bc/muffler-s

Luckily i already bought them just in case and have them in my parts bin. At 5 bucks a pop why not? I take it then that between the tapping noise and the carbon build up around that header that is a pretty sure sign of a leak then?

May as well fix it while i have time on my month at motoguild. Generally an exhaust leak isn't much more than a nuisance that robs a bit of power and fuel economy from my limited understanding, right?

 

[EastBayDave]

Luckily i already bought them just in case and have them in my parts bin. At 5 bucks a pop why not? I take it then that between the tapping noise and the carbon build up around that header that is a pretty sure sign of a leak then?

May as well fix it while i have time on my month at motoguild. Generally an exhaust leak isn't much more than a nuisance that robs a bit of power and fuel economy from my limited understanding, right?

One of them puppies leaking could be what your hearing. Replacing all 4 would just be SURE of getting the right one if you don't know which one it is.

Realize these copper washers are designed to "crush" to form the seal = so if one of the flange nuts came loose that might cause the leak. As I previously mentioned, just making sure all are tight might be the fix.

BE ABSOLUTELY sure to use a torque wrench on them. I've seen too many stripped threads or loose studs when folks don't use the proper torque. As mentioned, make sure the threads are cleaned & spotless...

Answering your second part of the Q is harder. In my experience, they just cause a leak that sounds like a loud tapping noise. However I've heard horror stories how a leaker could cause a burnt valve, bad performance, etc.

Changing all 4 out would just eliminate that as a possible source of the noise in my book. I always change them out during valve adjustments as part of the scheduled maintenance. Cheap insurance...

Good luck! :afm199

-ebd

 

[MoldTheClay]

One of them puppies leaking could be what your hearing. Replacing all 4 would just be SURE of getting the right one if you don't know which one it is.

Realize these copper washers are designed to "crush" to form the seal = so if one of the flange nuts came loose that might cause the leak. As I previously mentioned, just making sure all are tight might be the fix.

BE ABSOLUTELY sure to use a torque wrench on them. I've seen too many stripped threads or loose studs when folks don't use the proper torque. As mentioned, make sure the threads are cleaned & spotless...

Answering your second part of the Q is harder. In my experience, they just cause a leak that sounds like a loud tapping noise. However I've heard horror stories how a leaker could cause a burnt valve, bad performance, etc.

Changing all 4 out would just eliminate that as a possible source of the noise in my book. I always change them out during valve adjustments as part of the scheduled maintenance. Cheap insurance...

Good luck! :afm199

-ebd

Replaced my copper crush gaskets with new ones, tightened them, let the bike warm up, cool down again, and torqued them down a second time as per service manual. The torque spec for the exhaust pipe holder nuts isn't listed in my manual for some strange reason. It says to tighten them but doesn't list the spec, only the spec for the premuffler chamber mounting bolt which was 25ft-lb. Online I found reference to the pipe holder nuts being 13ft-lb in other Kawi bikes (2006 zx6r, ninja 650, versys 650, vulcan 650) so I just used that as my spec.

13ft-lb sounds a light amount of torque for this size of a bike but I can find literally no mention of the spec in either the manual or online. Akrapovic lists 22nm/16 ft-lb as the recommended for their full system exhaust for my bike though. Should I just go with the akra spec or keep it at the vaguely 13ft-lb that is generic for the other kawis i could find listed? Guessing that since the specs are rather close, it shouldn't matter much either way but always like to hear from more experienced folks.

I also disabled my exhaust butterfly valve leaving it in the wide open position since I couldn't get the cables back into the correct place and was running out of daylight. Read some positive comments from people who've done it about the change in exhaust note in low rpm and idle that seem to have held true. Made it sound a tad deeper up to 6k rpm when the thing normally fully opens. Feels a bit peppier in the mid range too, but that's probably just in my head.

edit: Found a chart for unlisted specifications in the manual for various thread diameters. For an 8mm thread diameter the spec is 10-13.5 ft-lb. Guessing since this isn't listed anywhere shooting for the 13.5 ft/lb isn't a bad bet?

 

[ctwo]

half a grunt on those...

 

[MoldTheClay]

That half a "ugh you are over thinking this fuck just do it" or a "turn it half a grunt past finger tight, whatever fuck it good nuff"

 

[ctwo]

Sometime you just gotta do. Is it still clanking at the tail?

 

[MoldTheClay]

Sometime you just gotta do. Is it still clanking at the tail?

Nada, sounds all good as it is now.