Loud ticking sound under timing cover

[Macamon]

1980 XS11SG
I have had a prevelent ticking sound under the timing cover since I purchased the bike at 7500mi. It diminshed somewhat (possibly my imagination) when I adjusted the timing chain. I just took the bike in to have the valves re-shimmed and when I got it back it was way louder. We removed the timing cover and I found the timing advance was rocking back and forth (aproximately in sync with engine revolution) and the sound was certainly coming from this. I removed the vacuum to the advancing motor and discovered a vacuum leak at the carb end of the hose. Having repaired the leak I still hear a loud ticking, mainly when I'm getting on it at low rpm's. It is not noticable at higher revs (or perhaps just can't be heard)

[cywelchjr]

1980 XS11SG
I have had a prevelent ticking sound under the timing cover since I purchased the bike at 7500mi. It diminshed somewhat (possibly my imagination) when I adjusted the timing chain. I just took the bike in to have the valves re-shimmed and when I got it back it was way louder. We removed the timing cover and I found the timing advance was rocking back and forth (aproximately in sync with engine revolution) and the sound was certainly coming from this. I removed the vacuum to the advancing motor and discovered a vacuum leak at the carb end of the hose. Having repaired the leak I still hear a loud ticking, mainly when I'm getting on it at low rpm's. It is not noticable at higher revs (or perhaps just can't be heard)

Was the line hooked to the port on the rubber carb mount or to the carb itself? If it's hooked to the rubber mount, that's the wrong place. It's supposed to go to the vacuum port on the number 2 carb, which should have little if any vacuum at idle, certainly not enough to be moving the advance assy significantly. It most certainly should not be jumping back and forth at idle though, that points to a problem.

[natemoen]

We removed the timing cover and I found the timing advance was rocking back and forth)

Was the timing plate wobbling or the advance mech just rotating? If the plate was wobbling the the shaft that it bolts onto is not seated correctly. There is a little dowel that it sits on and if it is not sitting correctly on that dowel then your timing could be off.

[Macamon]

I will check the mount point for that vacuum line when I get home. That definately sounds like the problem.

It was the timing advance assembly that was moving. There is only a slight "out of true" rotation of the disk at the end of the shaft 1/8"

[Larrym]

The Sound and the Fury...

Macamon,

Yeah... that noise had me concerned also. Even if everything is hooked up right and functioning perfectly it will sound like this:



Camera is mounted less than 4 inches from that cover/assembly so the noise is really captured well.

Keep looking and listening to your bike. You'll get familiar with the "normal" sounds and when something abnormal/wonky catches your attention be sure to stop and check it out.

Or invest in a fairing with a loud 8-track stereo installed to drown out anything that would otherwise provide a clue as to the bike's running condition. No fair using an I-pod with ear-buds to drown out any/all road and engine noises...

[nutwister]

LMAO Larry, I believe you are right though. The rattling is the centrifugal advance mechanism I think. Mine does it at idle if it's idling too low.

Mine idles at about 13 or 14 hundred. The higher idle seems to cure a lot of goofy low end problems too.

[cywelchjr]

LMAO Larry, I believe you are right though. The rattling is the centrifugal advance mechanism I think. Mine does it at idle if it's idling too low.

Mine idles at about 13 or 14 hundred. The higher idle seems to cure a lot of goofy low end problems too.

While it will rattle at low speeds, you shouldn't get any noise from it or any significant movement at idle. If you do, something is wrong somewhere as the port it's supposed to go to is ported vacuum, meaning there is little if any vacuum at idle. If it's not hooked directly to the carb itself, then it's hooked up wrong.

[Macamon]

Was the line hooked to the port on the rubber carb mount or to the carb itself? If it's hooked to the rubber mount, that's the wrong place. It's supposed to go to the vacuum port on the number 2 carb, which should have little if any vacuum at idle, certainly not enough to be moving the advance assy significantly. It most certainly should not be jumping back and forth at idle though, that points to a problem.

BINGO! The R-tard mechanic that worked on it forgot to reconnect the horns and got the fuel shutoff and vacuum advance swapped. Problem solved.... Now I'm getting a backfire :'0 During Warmup it backfires on the right side exhaust can, it pops with a ringing sound. When I turn off the choke the backfire goes away but she runs somewhat uneven and I still get some popping on shutdown.

[XS1100_OEM4ME]

R-tard

Is the R-tard mech that did the wrong vac hook up the same R-tard that adj your valves? If so, it could be one or more of your exaust valves is to tight. If they don't close well, un-burnt gas can leak into exaust, and cause backfire/poping

[79XS11F]

BINGO! The R-tard mechanic that worked on it forgot to reconnect the horns and got the fuel shutoff and vacuum advance swapped. Problem solved.... Now I'm getting a backfire :'0 During Warmup it backfires on the right side exhaust can, it pops with a ringing sound. When I turn off the choke the backfire goes away but she runs somewhat uneven and I still get some popping on shutdown.

If adding fuel (chock) removes the problem then you likely have an air leak somewhere in the intake track.
Rob

[dbeardslee]

Camera is mounted less than 4 inches from that cover/assembly so the noise is really captured well.

Larry - did you notice that, when you put the kick stand down in the video, it made almost exactly the same noise? You sure it isn't the heat shields on the exhaust rattling? There are a couple little mounting brackets underneath the heat shield that are welded to the exhaust. If the weld's break the bolts may still feel tight, but it can make a heck of a noise. JAT

[Larrym]

Heat Shield Bracket Racket???

Larry - did you notice that, when you put the kick stand down in the video, it made almost exactly the same noise? You sure it isn't the heat shields on the exhaust rattling? There are a couple little mounting brackets underneath the heat shield that are welded to the exhaust. If the weld's break the bolts may still feel tight, but it can make a heck of a noise. JAT

dbeardslee,

I'll take a look at those brackets/welds today. Truthfully I've never looked at'em since I checked out the exhaust before installing it. Been a few miles since that happened....

Thanks for the second set of eyes and ears, dbeardslee. I figure that's one of the best parts about sharing and interacting here on channel 11. I mean if I (or anyone for that matter...) miss seeing/hearing something then I won't know that I missed it cause I didn't see/hear it, right?

Maybe there's a way for me to get a video of the P/U assembly "chattering" as I drive round. Hmmm...another Video project? A chance to use the new "Picture in Picture" feature?? (Gawd!! These bikes are so "camera friendly"...)

Thx...