XS 1100 Special Engine Knock or clacking sound Help?

[dolphans1]

Should'nt be any hoses hanging down as you say. The sound your hearing is likely from the vaccum advance hose hooked up incorrectly. That hose, which comes from left-side ignition cover goes to #2 carb itself, not the intake boot nipple.
I don't have the Special, so don't have the 'octy'. Another member here who does can better explain or show pic of the hose configuration on the Specials.

Okay, there's a hose that goes from the left side top of the crank case that goes to the # 2 carb intake brass carb holder fitting.

Then there's 2 black hoses that just hang down, if I plug those to back of the air-intake, I get excessive flooding.

[dolphans1]

There should be vent hoses (kinda look like vacuum hoses) running from the battery and the middle drive and hanging down by the middle of the front of the swingarm under the bike.

If you still have the octy there will be a hose from the diaphragm to the #2 intake boot. The vacuum advance hose running from inside the left engine cover goes to the vacuum port on the front of the #2 carb.

Can you clarify what "octy" means ? original carburetor t y....?

So the vacuum advance hose coming from left side engine cover does not go to the front of intake manifold brass nipple?

Thanks for the input and if anyone has a diagram or photo how it should go, please share.

[dolphans1]

Here's a picture of the diagram off online manual:

[TopCatGr58]

Hey Dolphans,

Okay, where are these 2 hanging hoses attached to?? I'm thinking they are connected to the UPPER T' fittings between each carb pair. The upper T fittings are the float bowl vents, and need to be OPEN to VENT, folks will sometimes put a small lawnmower fuel filter on them just to protect them against bugs. IF those hoses/vents are capped/plugged, then the carbs WILL FLOOD!

Also, do you actually have the Octopus vacuum control valve, or has it been removed and bypassed?

You found and showed the Diagram for the Octy in your last post.

The vacuum hose that comes out of the left TIMING case cover goes to the #2 carb body nipple....not the intake boot synch nipple! The Octy vac. control line goes to one of the intake boot nipples, the other 3 should be capped off. IF the Timing case cover hose WAS attached to the intake boot, that would cause the ticking from the left engine side....it's unmetered vacuum pulses that would have the vac. adv. pot really jerking badly=ticking! The nipple on the #2 carb BODY is metered properly.

T.C.

[dolphans1]

Hey Dolphans,

Okay, where are these 2 hanging hoses attached to?? I'm thinking they are connected to the UPPER T' fittings between each carb pair. The upper T fittings are the float bowl vents, and need to be OPEN to VENT, folks will sometimes put a small lawnmower fuel filter on them just to protect them against bugs. IF those hoses/vents are capped/plugged, then the carbs WILL FLOOD!

Also, do you actually have the Octopus vacuum control valve, or has it been removed and bypassed?

You found and showed the Diagram for the Octy in your last post.

The vacuum hose that comes out of the left TIMING case cover goes to the #2 carb body nipple....not the intake boot synch nipple! The Octy vac. control line goes to one of the intake boot nipples, the other 3 should be capped off. IF the Timing case cover hose WAS attached to the intake boot, that would cause the ticking from the left engine side....it's unmetered vacuum pulses that would have the vac. adv. pot really jerking badly=ticking! The nipple on the #2 carb BODY is metered properly.

T.C.

Okay T.C. your post sheds a lot of clarification. Yes, the Octopus vacuum control valve is still on this bike.

The two that are hanging are on the upper T fittings between each carb.

The vacuum hose coming off the timing case cover, right now, as we speak, is currently attached to the intake boot.

I will pull off tank today and make changes and report back.

Thanks...!!

[BA80]

Those 2 hoses from the upper T's are bowl vents for the carburetor bowls and don't go to vacuum. They go to nipples on the top front of the air box so they vent to filtered air.

Those are only on the 78 an 79 carbs, they were eliminated on the 81 and up carbs as the vents were an extra hole in the intake bell (air box side) of the carbs.

The picture from the manual you posted is the octy (octopus/ named because of all the hoses a vacuum controlled fuel cut off valve) and those hoses are all fuel lines except the one at the bottom that says "to vacuum supply"

[dolphans1]

Knocking sound solved!

Those 2 hoses from the upper T's are bowl vents for the carburetor bowls and don't go to vacuum. They go to nipples on the top front of the air box so they vent to filtered air.

Those are only on the 78 an 79 carbs, they were eliminated on the 81 and up carbs as the vents were an extra hole in the intake bell (air box side) of the carbs.

The picture from the manual you posted is the octy (octopus/ named because of all the hoses a vacuum controlled fuel cut off valve) and those hoses are all fuel lines except the one at the bottom that says "to vacuum supply"

Yes Greg, you're correct, but I must have a 1980 air-box, because when I pulled in the bowl vent tubes to the nipples on top vent box, I got excessive flooding from filter air box about a year ago. Someone on this site told me I need to drill a hole through them to make it work, I'm not sure if the hole in plastic nipples were too small or what not, but literally, the air cleaner box would pool (fill-up with gas), literally, so I removed them.

I swapped the 2 hoses from the number one carb (vacuum) with the vacuum hose coming off crankcase and that knocking sound went away, so thanks everyone who contributed.

I will post a video of the bike running without knocking sound here.

[BA80]

Yes Greg, you're correct, but I must have a 1980 air-box, because when I pulled in the bowl vent tubes to the nipples on top vent box, I got excessive flooding from filter air box about a year ago. Someone on this site told me I need to drill a hole through them to make it work, I'm not sure if the hole in plastic nipples were too small or what not, but literally, the air cleaner box would pool (fill-up with gas), literally, so I removed them..

The gas WASN'T coming from those hoses. Make sure the holes you drilled are open and vented to the interior of the air box.

I swapped the 2 hoses from the number one carb (vacuum) with the vacuum hose coming off crankcase and that knocking sound went away, so thanks everyone who contributed.

I will post a video of the bike running without knocking sound here.

This makes absolutely no sense. There isn't supposed to be 2 hoses on the #1 carb boot, actually #1 boot port should be capped and only used for syncing. The vacuum hose for the octy should hook to the #2 boot and the vacuum advance hose should hook to the #2 CARB. It sounds like you have something ( I don't know what) hooked to the vent hose for the middle drive.

BTW, when I said the vent hose for the middle drive hangs below the bike I was wrong. It should go to a holder up under the seat near the rear of the gas tank. Brain fart.

[dolphans1]

The gas WASN'T coming from those hoses. Make sure the holes you drilled are open and vented to the interior of the air box.




This makes absolutely no sense. There isn't supposed to be 2 hoses on the #1 carb boot, actually #1 boot port should be capped and only used for syncing. The vacuum hose for the octy should hook to the #2 boot and the vacuum advance hose should hook to the #2 CARB. It sounds like you have something ( I don't know what) hooked to the vent hose for the middle drive.

BTW, when I said the vent hose for the middle drive hangs below the bike I was wrong. It should go to a holder up under the seat near the rear of the gas tank. Brain fart.

Greg, I don't understand, where would the gasoline be coming from?

The carbs?

I assumed the gas was being sucked out from the bowls into the filter box, and the bike would just bog down real bad.

As for the 2 hoses I switched, I just flip-flopped them around or switched them around.

The vacuum advance hose running from the engine crank case I disconnected it from the intake manifold boot brass nipple and I then placed it on the number 1 carb vacuum nipple. I then took the hose from the octopus diaphragm and placed it on the # 2 intake boot brass nipple.

I hope that makes sense.

Here is the video: http://youtu.be/lxRi85vfgRM

[BA80]

If the nipples aren't open and flowing freely it'll cause the carbs to flood and fill the air box with gas. That's why I said to check them to be sure they are open. I have 79 carbs on my 80 and had to drill mine also.

As long as when you say "crankcase" you mean the left engine cover then that hose should go to the #2 carb. There is no vacuum port on #1.

You have the octy correct hooked to the #2 boot.

[dolphans1]

If the nipples aren't open and flowing freely it'll cause the carbs to flood and fill the air box with gas. That's why I said to check them to be sure they are open. I have 79 carbs on my 80 and had to drill mine also.

As long as when you say "crankcase" you mean the left engine cover then that hose should go to the #2 carb. There is no vacuum port on #1.

You have the octy correct hooked to the #2 boot.

Thanks Greg, personally I never knew why someone would put air cleaner pods on this bike, but after putting on the air-box and lining it up, to the carbs, man-oh-man, now I know why. there's literally no space to work with.

I will buy some mini filters for those 2 hoses until I pull the box off again.