General Harley Davidson Chat Forum to discuss general Harley Davidson issues, topics, and experiences.
Sponsored by:
Sponsored by:

Engine Knocking

Thread Tools
 
Search this Thread
 
Old Mar 6, 2010 | 01:24 PM
  #1  
lostsstsol's Avatar
lostsstsol
Thread Starter
|
Cruiser
Joined: Mar 2010
Posts: 116
Likes: 0
From: Long Island, NY
Default Engine Knocking

Ok heres my issue.

I own a 2006 FLHXI with 15,000 miles on it and I completed a nice simple tune-up last night. Changed all 3 fluids, oil filter, plugs, and clutch inspection gasket, and primary chain inspection gasket. I also tightned my primary chain a little (per service manual) since it was loose. I just bought the bike used form a private seller and instead of taking his word for all the work said hey might as well do it myself.

Well everything went smoothly, toke the bike off the lift, and then toke it for a nice little ride before closing shop. Everything seemed nice, she ran smooth the whole time. While i was riding the bike home (earlier mentioned shop is at a buddys) i noticed a slight knocking coming from below me. I was only a block from home so continued home.

It seems the knocking is coming from around the clutch area of the primary. There is no knocking when the bike is first started and cold, but as it warms up it seems to get worse. My friend was saying my primary chain may have come loose but i will not be able to check it till Monday (work always gets in the way!)

I was hopiong maybe someone had an idea of what else it might be or if someone has had the same problem. The bike was running clean before the tune-up incase i didnt mention that.

Looking foward to some good tips!
 
Old Mar 6, 2010 | 01:37 PM
  #2  
texas_speed_freak's Avatar
texas_speed_freak
Road Captain
Joined: Jun 2008
Posts: 572
Likes: 6
From: Ft. Worth, Texas
Default

Originally Posted by lostsstsol
Ok heres my issue.

I own a 2006 FLHXI with 15,000 miles on it and I completed a nice simple tune-up last night. Changed all 3 fluids, oil filter, plugs, and clutch inspection gasket, and primary chain inspection gasket. I also tightned my primary chain a little (per service manual) since it was loose. I just bought the bike used form a private seller and instead of taking his word for all the work said hey might as well do it myself.

Well everything went smoothly, toke the bike off the lift, and then toke it for a nice little ride before closing shop. Everything seemed nice, she ran smooth the whole time. While i was riding the bike home (earlier mentioned shop is at a buddys) i noticed a slight knocking coming from below me. I was only a block from home so continued home.

It seems the knocking is coming from around the clutch area of the primary. There is no knocking when the bike is first started and cold, but as it warms up it seems to get worse. My friend was saying my primary chain may have come loose but i will not be able to check it till Monday (work always gets in the way!)

I was hopiong maybe someone had an idea of what else it might be or if someone has had the same problem. The bike was running clean before the tune-up incase i didnt mention that.

Looking foward to some good tips!
Two things come to mind.
1: There is a hot OR cold adjustment for the primary chain depending on whether your bike is warmed up or not. Make sure you adjusted it to the right specs.

2: There is a spot on the primary chain where it is tighter so you have to roll it around to find that tight spot before you adjust the chain.
 
Old Mar 6, 2010 | 08:58 PM
  #3  
lostsstsol's Avatar
lostsstsol
Thread Starter
|
Cruiser
Joined: Mar 2010
Posts: 116
Likes: 0
From: Long Island, NY
Default

sounds good texas i will do that when i readjust on monday. you think i should drop the whole primary cover to do it and refill all the fluid?
 
Old Mar 6, 2010 | 09:26 PM
  #4  
oldairboater's Avatar
oldairboater
Ultimate HDF Member
Joined: Jan 2008
Posts: 7,476
Likes: 5
From: Republic of Texas
Default

Doubt if it is a knock. More likely a primary chain slap. Pull inspection cover and check chain after rolling it in several places. Sounds like you either left adjuster loose or you slacked off the chain.
 
Old Mar 6, 2010 | 09:51 PM
  #5  
BLKBAGGER's Avatar
BLKBAGGER
Outstanding HDF Member
Joined: Oct 2007
Posts: 3,450
Likes: 4
From: El Cajon Ca.
Default

Could be that the compensator loosened up. It's pretty common. If you don't find your chain at fault that's where I would look next.
 
Old Mar 6, 2010 | 11:21 PM
  #6  
hatchetman's Avatar
hatchetman
Road Warrior
Joined: Nov 2008
Posts: 1,595
Likes: 8
From: Vancouver Island British Colombia Canada
Default

trans drive sprocket could also be coming loose! time to take a detailed look before something gets bashed.
 
Old Mar 7, 2010 | 10:04 AM
  #7  
texas_speed_freak's Avatar
texas_speed_freak
Road Captain
Joined: Jun 2008
Posts: 572
Likes: 6
From: Ft. Worth, Texas
Default

Originally Posted by lostsstsol
sounds good texas i will do that when i readjust on monday. you think i should drop the whole primary cover to do it and refill all the fluid?
I wouldnt worry about draining the fluid or pulling the cover. You just have to make sure you adjust it right. It can be tricky without a tool to measure the slack. You can take a metal coat hanger and put a couple bends in it to make you a good measuring tool.

Since it only started AFTER you serviced the bike and adjusted the primary chain i highly doubt it is the comp sprocket. Just a missadjusted chain slapping in there.
 
Old Mar 7, 2010 | 11:22 AM
  #8  
rounder's Avatar
rounder
Ultimate HDF Member
Joined: Oct 2007
Posts: 7,562
Likes: 11
From: Palm Harbor fl.
Default

How could tightening the chain cause chain slap from a previously looser chain? Unless the op actually loosened the chain or the tensioner slipped. Just wondering.
 
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

10 Most Awkward-Looking Motorcycles Ever Built

 Verdad Gallardo
story-1

Jason Momoa Is Turning Classic Harleys Into PHEVs

 Verdad Gallardo
story-2

Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom

 Verdad Gallardo
story-3

6 Weirdest Harley-Davidsons Ever Sold to the Public

 Verdad Gallardo
story-4

7 Times Harley-Davidson Chucked Tradition Out the Window

 Verdad Gallardo
story-5

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-6

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-7

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-8

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-9

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
Old Mar 7, 2010 | 11:33 AM
  #9  
Faast Ed's Avatar
Faast Ed
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
Default

Originally Posted by rounder
How could tightening the chain cause chain slap from a previously looser chain? Unless the op actually loosened the chain or the tensioner slipped. Just wondering.
If the nut wasn't tight after adjustment, that thing can drop to full loose instantly. Rattle city.
A too tight chain would likely whine noticeably loud.

Something odd about this story. I can't wait to see what he finds!
 
Old Mar 7, 2010 | 11:38 AM
  #10  
rounder's Avatar
rounder
Ultimate HDF Member
Joined: Oct 2007
Posts: 7,562
Likes: 11
From: Palm Harbor fl.
Default

Originally Posted by Faast Ed
If the nut wasn't tight after adjustment, that thing can drop to full loose instantly. Rattle city.
A too tight chain would likely whine noticeably loud.

Something odd about this story. I can't wait to see what he finds!
yeah if it is chain slap... the Op did something wrong... Like move the adjustor down instead of up, not tighten nut tightly, I dunno, I do know that the chain could not be tighter and then have developed chain slap.
 



All times are GMT -5. The time now is 12:56 PM.

story-0
10 Most Awkward-Looking Motorcycles Ever Built

Slideshow: Not every motorcycle can be a design icon, and these machines prove that bold styling doesn't always age gracefully.

By Verdad Gallardo | 2026-06-12 11:58:41


VIEW MORE
story-1
Jason Momoa Is Turning Classic Harleys Into PHEVs

Slideshow: Jason Momoa's latest restoration project blends 1920s Harley-Davidsons with modern electric technology, creating some of the most unusual hybrid motorcycles ever built.

By Verdad Gallardo | 2026-06-10 17:18:58


VIEW MORE
story-2
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom

Slideshow: Killer Custom's latest build relies on styling changes rather than performance upgrades, giving the cruiser an entirely different personality.

By Verdad Gallardo | 2026-06-03 18:28:05


VIEW MORE
story-3
6 Weirdest Harley-Davidsons Ever Sold to the Public

Slideshow: From military-inspired singles to scooters and three-wheel utility vehicles, these Harleys took the company far outside its comfort zone.

By Verdad Gallardo | 2026-06-02 18:34:10


VIEW MORE
story-4
7 Times Harley-Davidson Chucked Tradition Out the Window

Slideshow: Harley-Davidson built its reputation on nostalgia, but every so often, the company took a hard left turn into the future.

By Verdad Gallardo | 2026-05-20 11:18:19


VIEW MORE
story-5
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-6
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-7
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-8
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-9
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE