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[HD Street Performance]

OK just for discussion sake lets take power loss off the table...
The topic is constrained to HD twin cam performance motors with expected lifecycle same as OEM or better

We have an epidemic of lifter problems and valvetrain noise agreed?
The best of lifters are presenting with I don't know what that glazing is, not brinelling, not fretting??  Others are losing the roller bearings. Noise is lash, why and what can we do to cure that? Is spring pressure part of or at the root of the problem?

The spring just needs to get the mass (which includes the spring itself) in control so the lifter roller follows the cam lobe within the motors operating range and slightly above.

Current state of the art on forums is to blame manufacturers for inferior products when lifters fail. In some cases perhaps this is true but not the majority IMO. The noise chasers are trying all sorts of placebos at great cost with minimal returns.
Some suggest a high maintenance routine..
"May consider pulling/inspecting them @ 25,000 as service bulletins recommended, back in the Evo days."

My opinion
There will continue to be many lifter failures if the root cause is not found and eliminated. Oil is not the culprit nor the cure. The lifters, with the exception of some of the worst such as the HD -C, are not the root cause either. I have seen the best of them fail and very early like <6K miles. I suggest that valve spring pressure is a major influence but is not likely the only culprit.

Conclusion
Perhaps with adequate spring rate, a lighter spring mass (read beehive or conical), and lower seat pressures (same pressure over the nose we typically run) all of the bases can be covered.

Thoughts?

[rigidorbust]

I'm considering beehive springs, but what brand ?

[prodrag1320]

AV&V is what we use

[Ridgerunr]

The mother ship went to beehives in the 96" and 103" but kept the overkill springs in the 110", can't imagine their reasoning.

[INDEPENDENT_1]

Not sure what the cause is either. Is it possible the alloy the cases are made of have changed and the lifter bores are growing when they get heated up to a larger tolerance between lifter body and lifter bore and the result is what we've been seeing? Just a wild guess but is that a possibility? 

[Twism_23]

I put AV&V valves and beehives into mine this spring. I hope it helps!

[Dan_Lockwood]

I put AV&V valves and beehives into mine this spring. I hope it helps!

You said you put in the new parts listed above, have you ridden your bike since then?  The first ride should let you know if it has it helped?

Did the parts help you out noise wise?

[INDEPENDENT_1]

I recently had a set of MVA heads done and we ran a set of PAC conical "beehive springs" and it drastically reduced valve train noise.

[Steve Cole]

Here is a little food for thought. GM says the oil pressure below 16 psi is out of specification and will cause damage. Now I know that the GM  spec. doesn't mean much to you guys but let's start with it and assume for a moment that there is some minimum oil pressure requirement for a hydraulic lifter to work correctly. If you go below it your going to have damage. Now add to that specification the the oil pressure needs will be different based on the valve train components (ie: pressure and mass). GM lifter failures are little to none and we all know about HD's. Take the fact that the GM lifter for a LS1 type engine is a direct replacement for a HD and what have you got here? So the lifter works fine in one application and using that same lifter in another applications with similar camshaft design fails them right and left.....................

[INDEPENDENT_1]

Certainly a plausible thought, Steve. In my crate S&S 124, I have their cam plate and pump that is all gear driven (I think there's about 8 gears in there) I run near 32 psi oil pressure at hot idle. I only have probably 6k on it so far but I plan to do head work in the winter and put a set of the Of the S&S premium lifters in. Hopefully I'll have quite a few more miles on by then and I'll see what the current lifters look like.

[Steve Cole]

The problem is most if not all HD versions of the engine run at less than 5 psi at normal/hot idle. The bigger the engine the hotter it runs and the lower the oil pressure goes! So then people add oil coolers to cool the oil but it then adds a restriction to the oil system. I have not seen or heard of anyone testing oil pressure at the lifter and I know from the little work I've done that the pressure measured at various places around the engine varies a bunch so the 5 you see at idle maybe 0 at the lifter!

[ltank]

Spring pressure is determined by the cam used. High lift fast ramps require stiff springs to keep valves from bouncing causing major issues. In the past I had a bad ### Leinweber cam that required tripple springs.

[HILLSIDECYCLE.COM]

Just installed a set of Wood 180 psi springs on a Wood 408/98"/our heads/OE pump/plate/S&S lifters/pushrods loaded to .140"/rollers.
Spectro 50W. Zippers pressure shim.
Client wheeled it down I-90 from Albany, NY to us one day.
Even hot, quieter than an OE engine to the point the client even made mention of just that........
Scott

[Steve Cole]

All these various named lifters is a crap shoot at best. Most of them are all the same as there is only a few manufactures of hydraulic lifters world wide. Kind of like push rods, twenty people want there names on them but just a few making them. So if they all basically come from the same place, made out of the same parts why would you expect one or the other to last longer? Truth is they do not! Setup is the main player in this mess and using the right parts with acceptable oil pressure is what it's going to take to make the system live. As far as valve spring pressure you want the least amount of pressure you can have to get the job done. I will have to dig around and see if I can find an old video of the valve spring in action I had years ago. Changed the springs to not only a lighter one with reduced pressures and gained 20 Hp in a V8 engine along with 400 more RPM range!

[INDEPENDENT_1]

I know its more money and thousands of bikes out there are doing fine with the old stocker oil pump but I prefer the Feuling pump in the early TC's. I imagine the Thayer moves a lot of oil too I just haven't had the opportunity to use one yet. On another note, ,y new 2014 GMC Sierra with 5.3L all aluminum block/heads with variable valve timing uses 0-20W oil. When that gets hot... its basically like baby oil. That's a little scary to me but it does hold almost 9 quarts. IIRC GM used to claim 4 psi was enough to properly lubricate an engine and I understand volume is important but Im not so sure pressure needs to be better too. I'm no metallurgist, however.