That 'Tick At 2800" Noise....

[Propflux01]

I am curious as to what the consensus is of the 'Harley Tick' that many (esp. me) complain about when riding. Everyone says "its normal, its a Harley' or some other excuse, but my question is, what actually causes the noise? I know, of course, about the rocker lockers, and that associated cause, and have seen many bikes fixed using these, but, like mine, sometimes it doesn't fix it. So what exactly IS that noise? Is it a valve slamming a seat that hard? is it the lifter very minutely leaving the camshaft and then coming back down on it from an aggressive ramp? Is it some kind of 'natural harmonic'? Surely, there are many engines that don't make this sound, so on those engines, those aforementioned issues are not happening. This leads me to believe there is a cause that can prevent this from occurring. What are others thoughts on this?

[Don D]

Not all big twins do this. If they do it is valve train lash or piston slap. Hotter worse, most likely valve train, worse cold most likely piston slap.
To fix it goes the gammut but there are fixes and the specifics of the build need to be examined.
The fix is not lifter preload usually or rocker shaft shims.

[Rockout Rocker Products]

The fix is not lifter preload usually or rocker shaft shims.

If you mean rocker arm end shims I would 100% agree. If you mean inserts to keep rocker shafts from rotating.... thousands of bikes have been cured by them, more every day 

[Don D]

I use rocker lockers and those are one of many fixes that work, if the shafts are clacking.

[Propflux01]

I just cannot help wondering why some do it, and some don't. even ones equipped with lockers. Mine in point. Ive got lockers in all 4 holes and still clacks loudly, moreso when hot. Wife as a 2015 Switchback that is quiet. Mine you can hear bringing RPM up in the garage. Hers, quiet other than the normal sound of mechanical parts moving. Gotta be some kinda clearance, or part that causes this.

[tdrglide]

Some cam ramp designs are more forgiving of a standard valve spring pressure/geometry.

I did a little cam noise comparison using off the shelf S&S heads a few years ago. Using woods 9b cams. Idle was very quiet but started to click around 2200 peaking around 2800. Pretty quiet by 3200 rpms.
Swapped out to S&S 625's.
Quiet at all rpms. Swapped out again for DME598's. Again, very quiet. I even tried some 1.7 roller rockers with the 598's. Again, quiet.

Woods made the best power. 
So why the 2800 peak noise  .
Maybe above that rpm the frequency was too high for me to hear?  Or

[kd]

Have you confirmed that you have no exhaust leaks or heat shields close enough to make contact or rattle when the harmonics are just right.  That is a common thing that sounds like valve train noise and gets blamed lots.  A smoke test with a cigarette or the like around the exhaust ports when hot or cold and a small rubber mallet to tap around any attached parts like the heat shields can be helpful.

[Propflux01]

I've done everything I can think of. Took shields completely off, changed headpipe to a fuel moto, different gas, different oil, borescope inside engine to make sure nothing inside was coming apart. etc.

[Trouble]

My 2004 RK has done this since day one. In reading the Owner's Manual under ignition, I found insight into this condition which says in part,' in certain transient load conditions (as the throttle is opened) the timing changes from normal to fully advanced. At this point, the operator can sometimes hear a noise that is similar to pre-ignition detonation. This noise should not be confused with detonation, ... it is caused by the instant pressure rise in the  combustion chambers as the spark advances rapidly. This noise doesn't affect engine performance.' 2800RPMs sounds about right. I've got over 100,000 miles and it still does it and it still runs like new.

[Don D]

I've done everything I can think of. Took shields completely off, changed headpipe to a fuel moto, different gas, different oil, borescope inside engine to make sure nothing inside was coming apart. etc.

There is lash in the valve train. Plain and simple. Need to know more ti give an opinion and maybe help.
What lifters, What pushrods? Which cams? What valve springs and valves?

[smoserx1]

Is it some kind of 'natural harmonic'?

That would be my guess.  I can remember thinking to myself riding my 99 home the first time 22 years ago how much valve train noise it had.  221000 miles later it is still there after 3  different cams and 4 sets of lifters and an 88 to 95 inch top end.  The cams did shift the resonance point some (stock it was about 2500, 21N cams about 2900, SE 203s somewhere in the middle, but it is still there, loud as ever (or probably louder as my hearing is about shot). 

[Deye76]

"I've done everything I can think of."
Nobody I know that runs a Thunderheader experiences a tick anywhere in the RPM range. 

[fbn ent]

 .......

[Propflux01]

There is lash in the valve train. Plain and simple. Need to know more ti give an opinion and maybe help.
What lifters, What pushrods? Which cams? What valve springs and valves?

Ok, 96" to factory take off 103". Andrews 48h. Smith brothers .010 over pushrods. S&S premium lifters stock 103 heads, gasket, valves and springs. SE oil pump. Stock hyd plate.

[Hossamania]

There is lash in the valve train. Plain and simple. Need to know more ti give an opinion and maybe help.
What lifters, What pushrods? Which cams? What valve springs and valves?

Ok, 96" to factory take off 103". Andrews 48h. Smith brothers .010 over pushrods. S&S premium lifters stock 103 heads, gasket, valves and springs. SE oil pump. Stock hyd plate.

Was the noise there before the changeover?

[Propflux01]

Honestly, I do not remember. When I bought it, it had these swept out loud ass drag pipes on it. I reinstalled the stock header he gave me and some old rineharts. I did this at the same time the 103 and cam change came because the exhaust was off. It's ticked since day one after that. Just that little rpm range. Best way I could describe it would be if you could imagine the lifter goes past the top of the ramp and then slightly gets "airborne ", then comes down (taps) on the cam. Looking at the cam during my various checks shows no such indication of that. The ramps are nice and smooth and he lifters spear to have no play in the roller.

[Adam76]

Not all big twins do this. If they do it is valve train lash or piston slap. Hotter worse, most likely valve train, worse cold most likely piston slap.
To fix it goes the gammut but there are fixes and the specifics of the build need to be examined.
The fix is not lifter preload usually or rocker shaft shims.

Hi Don, just wanting to learn here - why do you say that's it's usually not lifter preload?
I think the OP has fixed length PRs, (0.010" over) so how do we know the lifters are preloaded at the right depth?
Thanks.

[Don D]

Question back do we care, if the lifters remain seated and preloaded during operation? Things can prevent them from remaining seated. Many of those can be self inflicted issues.

[Adam76]

Question back do we care, if the lifters remain seated and preloaded during operation? Things can prevent them from remaining seated. Many of those can be self inflicted issues.

Ok,  gotcha.
Thanks 👍

[Propflux01]

Question back do we care, if the lifters remain seated and preloaded during operation? Things can prevent them from remaining seated. Many of those can be self inflicted issues.

Can you elaborate more on this?

[Hossamania]

Have you checked for witness marks in the pushrod tubes?
Hattitude mentioned measuring and clearencing  the lower rocker boxes in his pushrod thread.

[Propflux01]

Have you checked for witness marks in the pushrod tubes?
Hattitude mentioned measuring and clearencing  the lower rocker boxes in his pushrod thread.

Yes, I've had it apart twice now. I honestly expected to find my issue there, but nothing, not on the tubes, or on the rods.

[hattitude]

Have you checked for witness marks in the pushrod tubes?
Hattitude mentioned measuring and clearencing  the lower rocker boxes in his pushrod thread.

Yes, I've had it apart twice now. I honestly expected to find my issue there, but nothing, not on the tubes, or on the rods.

I have mine apart for the 5th time....

For the record, the bike runs great... except for that tick.


I've changed pushrods 4X-  OEM, then Smith Bros solids (measured to be about +.020"), then SE Tapered +.030" solids, then S&S quickie adjustable

I've changed lifters 4X-  HD "B" lifters (w/20K miles), S&S Premiums, Johnson Hylift from WFO Larry (two types)

I've checked lifters and pushrods for debris, restrictions to the oil flow... all good

I've done the rocker arm plate mod oil return mod

I have added, and then removed Rockout inserts

I have changed the rocker bases to SE forged, and the rocker arms to S&S Forged (OEM size) and all measure well within spec... (not needed, just for the hell of it)

I have looked at the pushrod tubes, and pushrods with a magnifying glass and have been unable to find any witness marks. I have wanted to just drill out the tube tops, for the hell of it, but don't have access to a lathe

I've even had the cam plate out to check my work (cams, bearings, o-rings), and when it went back together, I put in an S&S TC3 plate/pump, just for the hell of it..

Through all this, that tick remains... Many of these items I did for the hell (read "fun") of it, because working on my bikes is my hobby... but the tick is really annoying me...!!

Since all that...

My dyno tune guy said he didn't notice anything out of the ordinary...

My new brother-in-law is a retired manager of a large HD Dealer, Service Dept. He has heard the noise, thinks it in the front rocker box, but thinks it's minor. He told me to look for a small, faint witness mark.. if any is there

Then I saw this video...

https://www.youtube.com/watch?v=yh1YmpNukDA

The part that caught my eye was from 0:45 seconds through 6:20..

It shouldn't apply to me, because I have OEM springs... but I thought .. what the hell.. I've tried everything else.

I did his procedure to a "T"...

When I tried to measure, an intake on the rear cylinder and an exhaust on the front, did not have the clearance he suggests...

I saw what appeared to be a small witness mark, on the front lower rocker box, within the area I marked with a Sharpie, where the clearance was too tight..  I tried to take a pic, but it doesn't really show up.

I clearanced both lower rocker boxes this morning, but won't get the bike back together for a week or so due to family stuff..

I'm kind of hoping this may be my tick... Don't know how, or why... but we shall see.

I'll report back as to whether it was a fail or a success, but it will be a few weeks...

[fbn ent]

I looked for signs last time I had mine apart....didn't see any. 

[kd]

I had a similar problem in one of my evo's.  It came on as the engine warmed up. The witness mark was no more than what appeared to be a black smudge. but I gave it a light buff with a grinder and that took care of it.  I eventually changed it when it started to leak also.   I think it was changing shape with the heat.  There was no actual dent or abrasion.  It just looked like a small black smudge.