Top End Tick

[sidecarKev]

So the past 1000 miles I've had an annoying tick. Thought it was a valve in need of adjustment. Went through the valves 3 times last night. All in spec. Adjusted cam chain. Still ticks. OK so I'm not 100% positive its on the top, but it REALLY sounds like its on the top on the left hand side. Cyl 3 or 4. I can really hear the tick at idle. Kinda hard to tell at highr RPM. I think I can hear it when under load but only if I'm not wearing a helmet. Don't really know when this tick showed up. The bike has always been a little noisy on startup but it usually went away when it warmed up.

Any ideas?

[ratbyk]

Ticky Tick

Suggest that you get a stethoscope (there cheap) and trace it down. Or get a long shaft screw driver. Place the end of the plastic handle up to your ear (tighter helps) and explore around the top area until you can pin down exactly where the noise is originating from. Who knows, may be nothing. But then again it could be critical like a broken valve spring or camshaft cap backing off.
Better safe then sorry. Go diagnostic.
Ken/Sooke

[strom]

I got the same tick....
As the valve spring/shim holding thingie rubs against the head when valve is opening/closing, it made some scratches there, but no biggie... I guess thats whats ticking in my case. Valves had been adjusted bout 900 miles ago, ticked before, then and now.
So... it's an old bike, it ticks a bit. No worries.

LP

[chevy45412001]

exhaust leak

Small chance of being an exhaust leak?at the head.

[sidecarKev]

I tried the screwdriver trick to see if I could pinpoint the location. Still sounds like its the loudest on the valve cover over 3 and 4. Oh well maybe it will go away. I'm just gonna keep riding it. I'll check my exhaust studs just in case. You never know.

[ratbyk]

Ticky Tick

Kevin, time to pull the cam cover had have a good look around. Recheck your valve clearances at least on the 3-4 cylinders. If nothing found recheck the torque of the camshaft cap mains.
Put your reading glasses on and visually have good look as best you can of all associated valve gear. (cam lobes, the buckets, shims, etc.) Possibly pull the spark plugs on the affected cylinders and see if they can give you any clues.
Something has too much clearance and is warning you. Whether it be a broken valve spring, valve spring collar, valve lock.
It is to bad that we have to do this diagnosis at long range. Being able to hear first hand the ticky tick would help. If it was my engine and I had to depend on it's reliability I know that I'd be digging deep. If it was an old beater I'd say turn up the radio but you already have so much time, money and effort in this bike , keep chasing it. Is that enough encouragement?
Lots of luck.
Ken/Sooke

[sidecarKev]

OK, OK since I still have the seat and tank off I'll give the valves another once over. I didn't check the shaft caps torque. The tick has that sound to it like you really need to adjust your valves. Like I said I went through the clearances 3 times to be sure. At higher RPM's exhaust noise takes over I think. But it can be heard while cruising along at 5000 and then suddenly accelerating. Other non-motorcycle people even ask me why it ticks like that.

[ratbyk]

Ticky Tick

Keven, since the seat/tank camcover are already off, if you still do not find problem, pull the ignition cover off left side of engine. With a good light, get your eyes, ears, nose what ever down in close. Get someone else to rotate the engine over while you watch each individual cam lobe go through a complete rotation. You are looking for something to "jump", make an unusual movement. Particularly as the lobe would start to open or as it starts to close the valve.
If still nothing found, take a small hammer. Using the butt end of the hammer handle and the head as a push point try pushing down on the edge of the bucket/cam follower. See if one is easier to push down on then it's brothers and sisters. If you find one the valve spring is broken/weak.
Just more diagnostic tricks/ideas.
Ken/Sooke

[sidecarKev]

Well now I'm not so sure that it the top end. I checked everything out up there. Clearances, torques, plugs, exhaust, changed oil and filter, filled the blinker fluid, whatever I could find. So I ran the bike around and drove it to work today. Checked it last night with a screwdriver to the ear. You know what? It all sounded the same. I have absolutely no clue where the darn noise is coming from. I was sure it was the top end. How's the saying go? If you ignore something it will go away. Maybe I'll give that a try. But actually I think its getting worse.

Its a definite tick under load and at idle. Anything else anyone can think of that I could look at? If it were bottom end would I know it? Wouldn't that be more of a knock?

[ratbyk]

Ticky Tick

Next trick, with the engine running and ticking, remove one spark plug wire at a time. If it still ticks put that wire back on and pull another. With luck the tick will stop when you hit the affected cylinder. It won't solve your problem but will narrow it down to one cylinder to chase.
I think stethoscopes are only like; $8.95 or so. The screw driver is a good trick but the stethoscope I believe does a better job. With a stethoscope and a white shop coat you can pass yourself off as a doctor of motors.
Is it possible that it is a small leak at a header pipe or cylinder head gasket?
Ken/Sooke

[ratbyk]

Ticky Tick

Further, a connecting rod knock is most pronounced on over run or as the engine coasts down from speed.
A noise in the valve train occurs at 1/2 engine speed. The valves only open and close once for two revolutions of the crank.
A tick type noise is usually related to the valve train because you are dealing with lighter parts. A noise from crank, rods, pistons is usually deeper and heavier in sound. Actually a piston makes more of a slap type noise because of the hollow shape of the skirt.
Ken/Sooke

[sidecarKev]

Well I pulled the plugs until I found the culprit. Its #3. Now what?

The valve clearances are ok on that one. The exhaust nuts are tight and had new exhaust gaskets when I refurbed the bike. I guess it could be a broken spring???? Man I really don't wanna have to pull this head. I tried your mthod of trying to check to see if there was a broken spring by pushing down on them but gave up. Couldn't get any to move because I really could't get much of anything in there to push with. Maybe its time to pull the cams.

[ratbyk]

Eurika!

Well now we are down to 1 cylinder. Progress has been made.
We know the problem is in the valve train associated with #3.
Go back again and get inventive. Somehow figure out a way to try and push down on the bucket/cam follower to determine if one of the valve springs is weak/broken.
Remember that as you do this test the valve must be in the closed position. (cam lobe up) If you can determine that one spring is easier to push down than the other we will be another step closer but if both a very stiff and the same it is not likely a broken spring. Oh, the intrigues of the internal combustion engine. Something has too much clearance. The trick is to figure out what? Before you start pulling cams etc. and getting inside and still not finding the trouble.
I have never had to replace springs or valve seals on an XS engine but have done it on many other engines without pulling the head. It takes an experienced engine man who knows what he is doing but it is do-able!
Pull the cams in the normal way, with all marks lined up. Once the cams are out all valves are in a closed position so you can turn the engine over (by hand) (keep track of the cam chain- possibly have it drawn up tight over a bar with some grease on it to allow it to rotate freely while staying hooked into the sprocet on the crank) none of the valves will tip a piston because they are all closed.
With the spark plug out of #3 bring that piston to TDC. This will prevent a valve from falling into the cylinder if something slips along the way.
Now again get inventive. You will need a lever of some kind ( a bar or pipe) about 16-18" long. A point on the bike or a piece of chain across to lever the end of the bar against. Your fulcrum point (the top of the valve spring collar) (after removeing the bucket/cam follower) needs an intermediate piece. Possiblly electrical conduit pipe or any piece of pipe the is about the same diameter as the valve spring collar. A piece of pipe about 4" long should suffice. Put a notch in this piece of pipe to locate the lever bar so that it will not slip. Cut two deep cut outs on the other end of this piece of pipe to allow finger clearance onto the locks. Get a trusted helper! You will need one person to compress the spring and another pair of hands to fish the locks (keepers) out.
Before trying to compress the spring at this point it helps to give a sharp rap with a hammer at about 45 degree angle against the side of the valve spring collar. This breaks loose the jamming affect of the locks/valve spring collar/lock grooves in the valve stem.
While the spring assembly is off the engine it is possible that the valve will fall down a bit and sit on top of the piston. When ready to reassemble take a piece of coat hanger or other stiff piece of wire. Bend a small hook in it, go down through the plug hole, hook under the head and ilft it back up in place. Pack some heavy grease on the stem where it enters the guide to hold it up.
OK ready to reassemble with new spring and valve seal. Get the helper back.
Kevin, before you attempt any of this exhaust all possibilities to determine exactly what is causeing the tick, tick.
Also read this over a few times so that you really understand what you are attempting to do. It is do-able but you will have to be a capable mechanic with a complete undestanding of what you are attempting. If you fail part way through you can always take the head off.
Lots of luck.
Do you have a digital camera with the capabilities of shooting a short clip with sound? If so you could shoot a clip of the engine up close with the sound picking up your problem.If so and the clip turns out OK send it to me at danielsken@shaw.ca. I will try and give you my opinion as to the source of your engine noise.
Ken/Sooke

[rneal55555]

I have replaced valve stem seals on car engines(small block chevy's mostly) by hooking an air compressor up to an adapter in the spark plug hole the air pressure keeps the vavle in place while the spring is off. You'd want to make sure the piston is all the way down or that the crank was some how held in postion so the the engine doesn't spin when you apply the air. Not sure is this would work on an xs but it's a thought.

[sidecarKev]

Holy crap, talk about detail. Ok I will be the capable mechanic taking this on. I've rebuilt a 4 cyl engine just last winter. Happened to be out of a '48 Farmall Cub though. I wish it was winter though. Really cuts into riding time. Give me a couple days to get things sorted out and I'll probably be getting back to you. I'll try pushing down on the shim/spring retainers with a piece of wood or plastic, something that won't scratch. I'll try to make something up that will work.

My camera can record mpeg's but not with sound.

Thanks Ken, you must have really thought this through.