strange sound from intake
#11
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
Could be the pressure leakage going past the rings on a partial compression stroke when shutting down. One time on a former Harley, I went to check the oil right after shutting down and a there was a big suction release when I removed the dip stick cap. Only happened once, but maybe I’ve never checked it so soon after shutting down. The breather passages in the intake do create a vacuum in the crankcase, provided there’s not a lot of blow by.
The following users liked this post:
ronbeejer (11-11-2023)
#12
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
IMO, I doubt that.. I've there will typically be any kind vacuum in the crankcase if the motor tops anywhere besides where the pistons are close to bottom of the cylinders.. What is the mechanism for the squeak?? I doubt it's the rings. How are you going to hear it?
Edit: I missed that there was a video file of the noise…just listened to it. I’m going with umbrella valves letting crankcase pressure out.
Last edited by RG Pilot; 11-11-2023 at 03:19 PM.
The following users liked this post:
ronbeejer (11-11-2023)
#14
#15
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
My 2022 did that initially for first 8000 miles than it stopped. I consider it normal. I agree pressure going out from somewhere. While I have no idea where it came from exactly my guess was it might be pressure escaping heads if valve is slightly open or he's mentioned earlier umbrella valve maybe. Tell your buddy not to stress about it.
The following users liked this post:
ronbeejer (11-13-2023)
#16
The following 2 users liked this post by Traildale:
Philiasfog (03-23-2024),
ronbeejer (11-13-2023)
#17
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
I have 2020 SG Cvo with not even 3500 miles yet and mine does this… sounds like Whoo…as something spooling down. Dealership said normal and will happen often and noise is out of high flow air intake. I believe he’s right.
The following users liked this post:
ronbeejer (03-24-2024)
#18
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
Try this, Just as your are about the turn off the bike, unscrew the oil did stick to equalize the pressure and then turn off the bike. If it does not do make the noise then you have confirmed the dealers statement.
#19
![Default](https://www.hdforums.com/forum/images/icons/icon1.gif)
My 2022 did that initially for first 8000 miles than it stopped. I consider it normal. I agree pressure going out from somewhere. While I have no idea where it came from exactly my guess was it might be pressure escaping heads if valve is slightly open or he's mentioned earlier umbrella valve maybe. Tell your buddy not to stress about it.