Does anyone know the best way to locate the source / cause of an engine noise? I have a whirring that gets louder once the engine is fully warmed up. I have an engine stethoscope but doesn't seem to help isolate location of noise. I'm thinking it is either Primary chain whirring on Hayden tensions (installed 1000 miles ago, so should be gone by now) Or maybe cam chain tensioner(s). Its a whirring, loud, metalic sound, not a tapping noise.

 

Im not sure if you have access to this but when I was a dealer tech for FORD we had a device that was called "electric ears". You had 6 long leads and a black box, you clipped the leads on to the vehicle in the area you thought the mise might be,and drive it(with a headset on" the leads were color coded, and you switched between colors etc. Antoher option is to raise the back wheel ane run the drivetrain in the shop, while stethoscoping the bike and engine cases etc. just be sure to have a fan blowing on the engine and be mindful of overheating it. Another thing on Harleys just go over it tightening everything up.
here is an NVH article, its auto related but same idea https://www.vehicleservicepros.com/i...diagnosing-nvh

 

take 30 min and remove primary and inspect

 

Cam chain tensioners. Try listening there also.

 

What year Twin Cam?

How many miles on the engine?

Have any modifications been made to the engine?

 

2010 12K miles. Just added a Man-O-War Motorsprocket (compensator) and a Hayden chain tensioner at the same time. Which is why my first suspicion was the primary chain. The inherent noise of a standard compensator is gone now, so the noise could have been there before.... but I suspect not. Yes, I agree, need to open primary and inspect. If primary side looks good; Next would be to open the cam side and look at the chains & tensioner.

 

That's more a solid sprocket with cushions than a compensator and the whirring sound is your primary chain I'm betting. I just went with the 30 tooth solid from evo industries and I can hear mine faintly. If you have a lot of runout it will be make more noise. Nothing to worry about as long as your chain isn't too tight.

 

Sprocket side runout was only 0.014in So that is not an issue. and I know it's not a conventional compensator....... which is exactly why I installed it rather that a hopefully better, but same old same old Baker compensator....... HD's design has been flawed for years. Thanks for the input. Much appreciated

 

What turned me off with the darkhorse sprocket is having to send it in should it need a rebuild that they sell the kit for. Must happen if they sell that rebuild kit.

 

Kevin Baxter of Twin Power suggested when I open up the primary to inspect; That I run it for a couple minutes to get a visual and an even better ear on any noises coming from the primary side. I've seen guys on YouTube make a temporary oil shield out of cardboard to make sure oil doesn't go everywhere from off the primary chain spinning. Still waiting to hear back from Ironhorse and Hayden to get more info on what to look for, before I open up the primary.