Very loud knocking

[maury]

GL1100.
Worst at low rpms as increase to 1500rpm and above smooth as silk.
Pulling in clutch handle makes no difference at all.
Seems to be in front of clutch....... left side more pronounced?
Performed a carb sync

[Fred Camper]

Is it the same noise with power on at all levels and power off (decel)?

[maury]

I'm not certain I understand what you're asking.
The noise occurs only at minimal rpms.
Disappears when rev up to around 1500rpm then smooth all through acceleration/cruising/deceleration, comes back when idle is reached.

[Fred Camper]

So you get it both when you launch and when you coast back down to a stop. That discounts a number of piston slap issues.

[maury]

No, I get it only when at idle.
Disappears quickly when accelerating from a stop.

[Whiskerfish]

If you have an IR gun I would test the headers at idle to see if they are close. Or failing that try to perform a idle drop procedure. If a jug does not drop out during the procedure that means it is not firing at idle. Synch is only checking the vacuum it does not tell you that each cylinder is in fact firing. A dead jug at idle can produce a nasty knock

[maury]

I am not certain what an idle drop procedure is.

Nevermind........... I found the info

[maury]

OK..... 1 and 3 are not hot on the exhaust header like #2 and 4 are.
I take it the small screw sticking straight down in front of the bowl drain bolt is where I am to adjust.
One of them is really stuck. I used my pilot screw adjusting tool and it BROKE at the flex inside.
Anything else I can use???

[Whiskerfish]

the image here shows the screw viewtopic.php?t=43626#p453009

[maury]

I appreciate the response but my 83' GL1100 does not have the plastic plug covered access as in the image.

[robin1731]

I appreciate the response but my 83' GL1100 does not have the plastic plug covered access as in the image.

On an 1100 it is a pot metal type material. If it is still there. If not it is just the brass screw.

[maury]

Finally got the idle adjustment screw tool.
That was the problem for sure.
Thanks !!

[maury]

So.......
Adjusted the idle adjustment screws.
As previously stated it was not running on #2,4 idle when first checked with IR temperature reader. Rechecked and all are equal now.
Rechecked sync and is good.
Idles much better with 90% of knocking/clanking.......... maybe describe as chatter gone.
2 things remain at idle.
- There is still a slight knocking/clanking at idle. If idle gets around 750 or lower it knocks/clanks very loudly.
- An occasional loud clank/pop occurs at 1000-1200 RPM idle.
Once above 1500 RPM......... absolutely butter smooth.
In trying to determine the location of where the slight knocking/clank is coming from it may be the #2,4 valves.
Will check clearances and timing in next couple days.

Then there's this.......
https://www.randakksblog.com/diesel-clatter/

Would appreciate any advice............

[Whiskerfish]

By the Honda manual Idle for the GL1000 should be 950 plus or minus 100. I "presume" the 1100 is close to that. Mine are all set for 1000 rpm or a bit higher. 750 or lower and all except the extremely well tuned will make noises and the charge rate is minuscule. That said it still sounds to me like it may not be pulling evenly at idle. If it bothers you, you can baseline all the idle adjustments (back to factory settings) and check your header temps again. That will identify which jug is weak and then go through the carbs again concentrating on that jug.

Or you can ride it Many times a few tanks of clean fresh gas can resolve small issues like this.

[redglbx]

Maury, have you checked the carb sync ? If not sync’d I have found that a lot of odd noise may occur, particularly if the idle is low. A good carb sync will make your bike just run magically. I usually set my idle at around 1100rpm even though Honda says 950 +/- 100. Like several have said it just charges better and runs smoother,,,, what does Honda know anyway ?