Dyna knocking
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
Are you using synthetic or conventional oil in your motor? When I had my RK with the 96" running synthetic the bleed down was awful making the knock sound like piston slap. An 'ol biker friend told me to swap the oil out with a good conventional oil and wait a few hundred miles. Told me to be patient and it would quiet down. He was right, it took about 300 miles and it quieted right down and stayed that way. Never used synthetic in the crankcase again in any of my bikes ever since. Dave ('ol biker dude who has since passed away) stated vtwins hate synthetic oil cuz it thins out too much causing all kinds of noise issues. FYI.
Advanced
Joined: Sep 2016
Posts: 64
Likes: 11
From: S.W. FLORIDA
Are you using synthetic or conventional oil in your motor? When I had my RK with the 96" running synthetic the bleed down was awful making the knock sound like piston slap. An 'ol biker friend told me to swap the oil out with a good conventional oil and wait a few hundred miles. Told me to be patient and it would quiet down. He was right, it took about 300 miles and it quieted right down and stayed that way. Never used synthetic in the crankcase again in any of my bikes ever since. Dave ('ol biker dude who has since passed away) stated vtwins hate synthetic oil cuz it thins out too much causing all kinds of noise issues. FYI.
I run synthetic oil in everything I own and have yet to have any issues at all with any of my rides. 2009 Jeep (156,000mi.) 2016 Mitsubishi (85,000mi.) HD SuperGlide (36,000mi.). If you have a noise I doubt its caused by syn. oil.
Stellar HDF Member
Joined: Feb 2013
Posts: 3,072
Likes: 1,726
From: Dallas, Texas
Easy way to pin point the noise - long screwdriver stethoscope. Point of screwdriver on engine, end of handle against your ear. LISTEN for the noise. Move it around the engine till you find it.
Cruiser
Joined: Oct 2013
Posts: 138
Likes: 12
From: Milwaukee
X2
I use this method all the time, it works great.
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
That ^
Pull the exhaust and cam cover asap, inspect the cam chain tensioners (especially the inner one). Or spend a lot of time chasing something else. When you hear hooves, look for horses, not zebras. Whatever you do, don't continue to ride it until you've determined the cause.
Pull the exhaust and cam cover asap, inspect the cam chain tensioners (especially the inner one). Or spend a lot of time chasing something else. When you hear hooves, look for horses, not zebras. Whatever you do, don't continue to ride it until you've determined the cause.
Advanced
Joined: Sep 2016
Posts: 64
Likes: 11
From: S.W. FLORIDA
Dyna Knocking
I generally try to find the general area that noises are coming from before tearing into an engine. It makes it a lot easier to find the problem when you have a general idea where it is coming from. The screw driver method works well but a piece of steel automotive fuel or brake line works great. What ever you use find out affected area before you start tearing into, it will save you a lot of work and trouble down the road.
Seasoned HDF Member
Joined: Nov 2016
Posts: 5,801
Likes: 809
From: South Carolina
Goin to sound crazy... Change the oil filter, I got a bad filter my last change and I was making the same sound.
Hopefully that's it
Good luck there
Hopefully that's it
Good luck there
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider
Verdad Gallardo
Advanced
Joined: Sep 2016
Posts: 64
Likes: 11
From: S.W. FLORIDA
First thing I I would look at would be the octane of the fuel. You may be going past the "pinging" phase and into pre-ignition. The other thing to check is carbon build up That will cause hot spots and pre-ignition. I have also seen carbon build up on piston tops hitting the combustion chamber causing a knock.. A dose of sea foam has helped in those cases.
