Noisy valve train

[kentiem]

Last year I upgraded my 1997 EVO engine (50000 km) to an Andrews EV27 cam. The engine did run very well after te mod but the valvetrain became quite noisy generating a clicking noise (like with lose tappets). First action was to replace the hydrolic tappets - made no difference. I have since pulled the cam again and had the original HD cam gear installed on my new cam shaft. Also, I did check all clearances and found nothing wrong.
Gear noise is still there but now seems to be depending on speed/ engine revs. When riding at 100 or 120 km/ph valve train is quite, when riding at 90 or 110 km/ph valve train is quite noisy. I want to stress that the engine has covered 5000 km with this configuration now and is running fine - I do not like this valve noise though and am looking for suggestions as to how to fix this problem.

[sbc charlie]

what type of lifter did you use. there has been a recall on some lifters
in the aftermarket people. is cam end play ok? check the roller real close
and make sure you have push rods installed correctly. my ideas or
problems seen in the past thanks
short-block charlie

[kentiem]

Lifters are standard HD - any suggestion as to how to check these? Cam end play is ok. I am using Crane time saver pushrods. Its difficult to understand why timing gear is only noisy at certain RPM bands.

[SDE]

That is my bike TOO!!! Did the same thing. Had EV 27 in and then out put my stock gear on it and back in. Then put SE4 with stock gear. Andrews time saver pushrods. Crane roller rockers, Jims lifters and lifter blocks. It is the best it has been all year right now. ( I think just because of the cooler weather!) but still not happy. 55 to 60 miles an hour fairly quiet 65 miles an hour sounds like pushrod is come through the bottom of tank drives me crazy! Keep in touch I am not going to give up untill I figure it out. Just got a matched set of cam and pinion gears from harley yesterday. Going to try this in a week or two. If you get anywhere with yours let me know I will do the same. Thanks Shawn. shawn.eaches@coshocton.com

[gyrogary]

Maybe there are no unusual noises, just normal engine noises transfered by a bad engine top stabiliser mount up through and amplified by the fuel tank?

[tejanodrum]

I bought my 97 Evo Ultra with 32,000 on it and it has a terrible valvetrain noise. It is the loudest valvetrain noise i have ever heard from an engine. I am a mechanic for 22 years and this is my first Harley. I've had it to the shop and they said everything is fine. I've got to admit the bike has 42,000 on it now and it still runs good. The noise seems to come and go. Mostly around 60 mph or 2000 rpms. The bike reminds me of a sewing machine. When i shut it off i hear a strange noise like a broken piston skirt on the front jug. Also the front jug is the noisiest. I love my bike but the noise drives me crazy. I haven't tore into it yet but i do know that i have aftermarket pushrods. I will have to tear it down soon because i can't stand it anymore. Anybody have any ideas? Tejanodrum

[ROY YOUNG]

Just something for you guys to think about, I'm running a Wood's 6H which is a very agressive cam with roller rockers also. I'm also running the SE lifters with it. Mine is really quiet even though it is in an Ultra-Classic. Sometimes the lifters tend to bleed off too much when they get some age on them. Also don't forget that HD says to run 50wt. oil after the temp. reaches 60 degrees, and 60wt. at 80. All this is assuming the lifters are adjusted correctly also.

[barrybasinger]

Originally Posted by ROY YOUNG

...Also don't forget that HD says to run 50wt. oil after the temp. reaches 60 degrees, and 60wt. at 80...

I'm not gonna go get the Evo manual to look, but I think it says HD 360 (20-50) in all common temp ranges, with the straight weights optional at the temps mentioned above.

[barrybasinger]

Originally Posted by tejanodrum

...The noise seems to come and go. Mostly around 60 mph or 2000 rpms. The bike reminds me of a sewing machine. When i shut it off i hear a strange noise like a broken piston skirt on the front jug. Also the front jug is the noisiest. ...

Gear backlash seems to be most evident at about 2000-2500 RPM (60-65 MPH). This backlash momentarily unloads the valevetrain, allowing any slop anywhere to make more noise. Front jug is often noisier because this is where the worst pushrod angle is, accenting several kinds of symptoms.

Common causes of noise at this RPM:
~ excessive gear lash. Swapping gears is the cure. Or ignore.
~ pushrod hitting the tube. If rod is not bent, trim the tubes. Or ignore.
~ lifter roller bearings worn. Replace them right now! Now! Go!
~ rockers hitting the covers. Clearance the covers. (And check for bent pushrods).
~ Bushing in cam cover worn. Re-bush and re-clearance. (What a pain)!

Less likely:
~ cam lobe galling. Replace lifters, cam, and inner bearing. Replace plastic breather. Flush engine oiling system. Check oil pump for damage.
~ bent pushrods. Replace.
~ pushrods come out of adustment. I suppose it can happen.

Broken piston (at shut-off???) often causes a higher-pitched "rapping" noise, with distinct taps much more evident when engine is cold. The "sewing machine" noise is almost certainly valve-train.

[Fourcats]

Check the fit of the rocker arm bushings/shafts, they may be worn and "egg shaped".

[frydaddy96]

Not to be a smartass, my 96 EVO has valve train noises too. I tried different weight oil which seemed to help until the oil temp is up to around 200 then the noises were back. I talked to several people and basically got do one or all three things.
1. put in ear plugs
2. take off the windscreen
3. ignore it
if its running good don't woory about it. It's a Harley V-twin and an EVO.

[bikersphd]

I have been building race eng. pretty much my whole life I’ve had the opportunity to spend hundreds of hours trying different things on the Dyno (which has left me talking to myself a lot) not saying this is your problem but springs inherently have a harmonic problem at certain rpms basically they stop working if you ever noticed dowel springs the outside: cowl is wound one direction in the inner spring is wound the other direction this is among other things an attempt to counter act the harmonic problem . Like I said this may not be you problem?
I have a 2000rk twin cam I made it 95” Mackie .590 gear cams and at 70mph it sounds like lifters are coming out that’s right at about 3000rpms drop a100 or raze 100 its gone so I pulled it a part checked everything back lash gears you name it if it was even remotely questionable I fix it .still same thing. I decided to try a different set of springs I set them up to the same tensions I still have the problem but now it’s at a different RPM . to make a long story short I’ve tried out four different kinds of springs .
I have the woods knight prowler springs on it now and my problem seems to be fixed .
Our these springs right for your setup I don’t know the difference cam profiles cause different spring harmonics .
This little tidbit is just something for you to think about when you lying in bed at night and can’t sleep . good luck With whatever you decide to do!

[ROY YOUNG]

Originally Posted by barrybasinger

I'm not gonna go get the Evo manual to look, but I think it says HD 360 (20-50) in all common temp ranges, with the straight weights optional at the temps mentioned above.

Your absolutely correct Barry as as near as I can remember. The chart I beleive says both, you can run either. The point I wanted to make is that you see more posts on here about EVO's and TC's both making noise than about any other one subject, and it's so easy to change the oil (if it's happening under very hot conditions) to see if it eliminates some of the oil by-passing the lifters that often happens causing what we might assume is another more serious problem.

[fxstc94]

most srings have dampers on the springs to controll these frequencys

[barrybasinger]

Originally Posted by bikersphd

...springs inherently have a harmonic problem ... they stop working if you ever noticed dowel springs the outside: cowl is wound one direction in the inner spring is wound the other direction this is among other things an attempt to counter act the harmonic problem ....

I've been thinking about this since I read it, since I had never considered the possibility that springs could be responsible for the kind of noise referenced here. Interesting idea. Since I've never designed a set of springs, I cannot say anything about their design of my own direct knowledge, but I have read a little.

All springs have a cycle (frequency) of compress/release at which they will begin to develop an oscillation "on top of" the frequency of compress/release. This oscillation is the natural harmonic of the spring. In a single coil spring, this can occur within normal operating range of the engine. If it happens, it can cause the instantaneous pressure on the valve to weaken, strengthen, or otherwise be changed. While this will not cause the spring to "stop working", it can certainly cause it to fail to return the valve to the seat in the manner intended.

As I understand it, manufacturers design spring sets with inner and outer springs wth differing harmonic frequencies for this reason. The combination of inner and outer springs can dampen the resulting harmonic oscillation, or, particularly with interference-fit springs with flat-wire inners, cause it to occur above the reasonable or physical capabilities of the engine on which they are installed. (This would not seem to be too difficult with an engine that may come apart at 7000 RPM or so like an Evo--unlike auto engines).

While I certainly don't claim to know enough to say it's impossible, I will say that I think it's doubtful that the springs directly cause the problem, or that changing them can cure it--assuming that the installed heights and pressures were all the same. I'd be happy to learn more from anyone, though.

My Evo is very quiet in the valvetrain. Several people have called it the quietest they've heard. That's because I've spent time with adjustment, trimming tubes, lifter fit, cam gear fit, etc.

Of all of the factors that I think are involved in this kind of noise, I still think cam gear lash is the most common root cause. I also think the noise can be safely ignored in nearly all cases--the most common exception being impending lifter failure. In my experience, that usually makes a hell of a racket and a much more solid rapping sound.

A belated welcome aboard, by the way. Always good to hear from someone else who will actually take the time to test ideas on a dyno. We all learn from what you guys do, and the work of all of you is appreciated by those of us who get to a dyno only a couple times a year.