Ticking Sound; I think I've ruled out exhaust gaskets.

[ff255away]

What else causes a ticking sound? This all started the day I installed NGK BPR6EIX plugs last Sunday. After 15 minutes of riding faster than I should, I heard a sound, lost some torque, and after getting off the freeway heard a ticking sound. I learned about using a screwdriver to isolate where the ticking was coming from, and determined it was the the number 2 exhaust gasket. Last night, I finally found time after work to purchase and replace the gaskets, doing all 4 at the same time.

I turned the bike back on afterwards, and there is still a ticking sound. I've checked every cylinder by the spark plugs and every pipe at the gaskets, and can't figure out where it is coming from. From what I understand, excessive valve clearance would be audible at the cylinder- do I need to check somewhere else?

Or, do I need to rip the engine apart?

::EDIT:: Several things I think I can rule out but haven't checked since the noise- carbs were synced hours before replacing the spark plugs, which were swapped out only a couple hours before blowing the gasket. I don't think its the carbs. Its a 1980 special, so the timing is supposed to be locked in stone, is this something that can be dislodged? There are two different weight oils in it, which now that I think about it, is probably something that should be fixed. I'll be swapping the oil out, and will be back afterwards.

[ff255away]

Can't seem to edit the original post, but here is a video I've uploaded. Its a phone video, so the ticking sound is pretty hard to hear until the last several seconds of the video.

http://youtu.be/eJKqkEHK9mE

[motoman]

What else causes a ticking sound? This all started the day I installed NGK BPR6EIX plugs last Sunday. After 15 minutes of riding faster than I should, I heard a sound, lost some torque, and after getting off the freeway heard a ticking sound. I learned about using a screwdriver to isolate where the ticking was coming from, and determined it was the the number 2 exhaust gasket. Last night, I finally found time after work to purchase and replace the gaskets, doing all 4 at the same time.

I turned the bike back on afterwards, and there is still a ticking sound. I've checked every cylinder by the spark plugs and every pipe at the gaskets, and can't figure out where it is coming from. From what I understand, excessive valve clearance would be audible at the cylinder- do I need to check somewhere else?

Or, do I need to rip the engine apart?

::EDIT:: Several things I think I can rule out but haven't checked since the noise- carbs were synced hours before replacing the spark plugs, which were swapped out only a couple hours before blowing the gasket. I don't think its the carbs. Its a 1980 special, so the timing is supposed to be locked in stone, is this something that can be dislodged? There are two different weight oils in it, which now that I think about it, is probably something that should be fixed. I'll be swapping the oil out, and will be back afterwards.

That Midnite still got the stock exhaust? If so, check CLOSELY for pipe fractures where the two go into one on underside. A common problem with the stock ,aging exhaust.

[skids]

The plug wires can jump spark to the engine and make a ticking sound. Wires good?

[natemoen]

Exhaust gaskets can sound like a knock.

[3Phase]

ff255away,

Welcome to the forum!

Your video seems to be marked Private and YouTube won't play it for me so I can't "hear" the noise.

Have you checked the cam chain tensioner? The stock cam chain tensioner has an annoying "feature" that allows it to back off and lose tension on the cam chain. If the tensioner moved then the loose cam chain would make a ticking sound and you'd lose power because the valve timing would be all over the map.

DANGER! You have to be very careful when you do anything at all that involves the cam chain tensioner or you'll almost instantly join the, "I had crunchy valves for lunch!" crowd at the cafeteria while y'all shop around for some new valves that aren't crunched.


To set the cam chain tensioner:

Put the bike on the center stand.

Remove the spark plugs. It's not absolutely necessary but it makes turning the engine a lot easier to do.

Remove the left-hand engine cover.

SLOWLY turn the crankshaft CLOCKWISE until the letter "C" on the Timing Plate lines up with the Timing Pointer.

Maintain smooth, even tension on the crankshaft as you align the "C" mark with the pointer.

DO NOT EVER! try to align the "C" mark with the pointer by turning the engine counter-clockwise even 1/1000 of a fine frog hair. The reason for the "C" mark is that it positions the engine at a point when there is the most slack in the cam chain at the "front" of the engine where the tensioner lives and holds the tension on the cam chain at the "back" of the engine at a point where where the crankshaft and camshaft are least likely to move as you're setting the cam chain tensioner.

When the "C" mark is aligned with the pointer, loosen the lock nut on the side of the cam chain tensioner, then loosen the stopper bolt. The tensioner spring should allow the tensioner plunger to move into place with the correct tension.

Tighten the stopper bolt to 4.3 ft/lbs, then tighten the lock nut to 6.5 ft/lbs. Do not over tighten either one or you'll strip the threads and possibly rip the stopper bolt right out of the tensioner.

Put the cover back on the left-hand side of the engine with one bolt so you don't snag yourself, your clothes, or anything else on the Timing Plate, then start the engine and listen for the ticking noise.

.

[ff255away]

Exhaust was replaced last september. I've been checking the joints and they sound normal. After a quick drive to the store and back and tightening the exhaust down, the clicking is in the 1 and 2 cylinders.

My current guess is a much needed valve adjustment; and I'll look at the spark plug wires, they should be fine though.

[natemoen]

Exhaust was replaced last september. I've been checking the joints and they sound normal. After a quick drive to the store and back and tightening the exhaust down, the clicking is in the 1 and 2 cylinders.

My current guess is a much needed valve adjustment; and I'll look at the spark plug wires, they should be fine though.

These valves get quieter when they wear, unlike other valve trains that get louder as they wear.

[skids]

These valves get quieter when they wear, unlike other valve trains that get louder as they wear.

You sure about that? Shim clearance usually gets tighter and that causes the valves to open wider. Clakity clak

[natemoen]

You sure about that? Shim clearance usually gets tighter and that causes the valves to open wider. Clakity clak

The noises come from the cam lobe slapping the shim bucket as it rotates. Since as the valve train wares the bucket rides higher and higher in head then the cam has less distance to travel before it hits the bucket until it is always touching the bucket.

Try slapping someone from an inch away, now slap them from a foot away, which makes more noise...

[3Phase]

Well, yeah, the valve clearances do tighten up and get quiet as the valves and seats wear but they're really, really unlikely to do that and lose noticeable engine power in fifteen minutes of fast riding.

It is possible that the valves were already too tight and one of them burned during the bast down the road and a compression check on a 'new' bike is always a good idea anyway just so you have an idea about the engine's health but give the poor new guy a break!

Resetting the stock self-unadjusting cam chain tensioner before you get all paranoid and stuff is a lot easier to do than waiting overnight for the engine to cool off for a cold compression check and valve shim measurement, or freaking out and tearing off the head and staring the valves and valve seats!


.

[skids]

The noises come from the cam lobe slapping the shim bucket as it rotates. Since as the valve train wares the bucket rides higher and higher in head then the cam has less distance to travel before it hits the bucket until it is always touching the bucket.

Try slapping someone from an inch away, now slap them from a foot away, which makes more noise...

I was thinking that the valves could be making noise with tight shim clearance. Hell, I don't know...just keep the valves adjusted!