Dirty with what ???

WP

 

Some kinda dark shmutz, not metal. Didn't make a difference though in the lifter noise.

So I took the tank off AGAIN... and pulled the plugs and noticed a little, shiny flat spot on the back of the little metal tang thing that grounds the electrode for the spark. I'll be damned if that wasn't from the friggin valve hitting it!!!

So, vice up the spark plug, tap the tang in with a hammer just a ****** hair, reset the gap, and file down the offending location. I also checked the index of the plugs (where the electrode points when installed) and that one's pointing right at the huge-*** intake valve. I spun the motor in gear and watched the valve, I'm positive that's what's doing it. I thought it was the domed piston at first but when I seen that valve start opening it all made sense. With any luck that was my knocking.

I also added .025" preload in the pushrods. Now total is .125".

I'll try again after dinner.

 

Ok, here's what's up. Liked the 27.5 pilot, probably take it down to the 25 since around town was rich until I took the idle mixture screw out past 2 turns. Got out on the highway, stayed in the right land and kept it in 4th. AFR's in the 12's constantly. Very light acceleration was in the 11's.

Still got that weird intermittent knock though. I only hear it sometimes. Sometimes it's on the left side, sometimes on the right. The right side certainly sounds like lifters. Left side sounds like a piston slap. It's the strangest thing tho because sometimes it's there, sometimes it's quiet and all I hear is valvetrain chatter.

Any suggestions?

 

I should add, on the way home in 3rd I hammered the throttle. Not WFO, but pretty deep. The bike damn near shot out from underneath me but the motor sounded cleeeeeeannnnnn with no knocks, pings, or anything funky.

 

I would also like to add that when I did my heavy throttle pull she yanked WAY harder than the M8 Road King I rented on Oahu in Feb of 17.

 

Ok, lifter knock was definitely the shitty chinese lifters. I swapped them out with a set of Hylift Johnson slow leak lifters (B-2303-S) with .075" preload. I injected them with some 10W40 before install and they were quiet as a mouse after about 3 seconds of idling and never piped up again. Made it really easy to hear the piston slap from the country mile of clearance I've got now...

Also, damned if I can remember what pilot jet I put in but my town cruise was much leaner. Cooler engine off idle but no choke was in the high 13's. I think I put the 25 in but I'll have to check. Also, 2 turns out at that AFR. Highway was still plenty rich.

Gonna play around with it some more tomorrow.

 

.075" preload is no where's near enough. Even the oem pushrods on a stocker are .100". might get noisy when hot....

 

I know but, H/J specifically says 20 to 40 thou. I know 100 is the norm and starting point, and the HD consensus is that 125-140 thou is the quietest but that's what the manufacturer says. I basically split the different and went 75 thou.

Lets think about this for a sec. What exactly does preload do? Imagine a lifter, preloaded to half its stroke. When it undergoes valve lift the spring pressure compresses the lifter and I'm sure it goes down some, but based on the hydraulic nature of these lifters since you can't compress liquids, the preload should stay relatively consistent while the engine is running. If that's the case, what's the difference between 20 thou and 150 thou? (aside from the cylinder growth of HD engines of course)

H/J's justification is that running a lot of preload beats the **** out of the internals of the lifter. Lets say during normal, HIGH SPRING PRESSURE applications the lifter compresses 50 thou at the onset of spring pressure, then regains this loss as the valve opens. If you run a lot of preload you may have some internal metal on metal contact in the lifter and in turn, shorten its life.

To be honest though, I have no idea what happens to a lifter under use. Does it compress? Does it stay at your preload setting until you turn the bike off and the lifter bleeds down? I've heard of lifter pump, but that's in really high RPM applications with valve float so I doubt that's happening in any HD engine with lifters.

 

To each their own..... You built a big inch, hi compression motor that will expand (grow) more than a stocker. Higher compression more heat... More heat more expansion..

Any ways, the hydraulic lifter works as a cushion to aide in keeping the valve train quiet and this is why the hydraulic lifter came about. .If you do experience metal on metal then the check ball in the lifter no longer is seating allowing the oil out of the lifter or the plunger clearance is beyond normal serviceable limits and should be replaced.. A well machined lifter will have approximately .0001" to .00015 clearance between the plunger and the lifter body this is where you loose a little of your fluid and don't be fooled by pump up. There is no way an oil pump can overcome valve spring pressure and hang open a valve but a weak spring can cause valve float which is not good....

When choosing a performance cam you need to make sure that the spring is strong enough to keep the lifter roller in contact with the cam and prevent valve float. Performance cams have a faster rate of ramp when both opening and closing. Most valve train noise is created when the lifter roller is falling off the back side of the cam lobe but with a stronger spring and deeper preload this helps to prevent excessive noise (keeping the roller in contact with the cam lobe).

Actually when I first started getting into modifying Evo motors and running big cam's like the Woods 8 (which can be a very noisy cam) I would set the preload to what Scott said back then "4 full turns" Well when the motor warmed up I would still get a decent amount of valve train noise and being as **** as I am I wasn't going to let it be. So I experimented with more preload going a flat at a time and when I got to the point of 27 flats or 4.5 full turns the valve train was very quiet when hot... I even set them at 28 flats with no issues at all. In fact I think on some motor builds Scott is recommending .150" Now

The real issue here is when you go to a bigger "high Performance Cam" do you want to deal with a noisy valve train or not. It's all about what you want , noise or no noise.... Also setting the preload to different depths will not make any difference on valve train wear. The springs are the real culprit here coupled with the aggressive ramping of a high Performance Cam..

Keep in mind this is all based on a lifter with total travel of .200" and not a limited travel lifter....

 

Yep, 4 turns with square lobed cams.

Why are automotive brakes slightly spongier when the pistons are at full travel with low brake pads compared to new pads and the pistons are compressed in the bore? Fluid compresses more over length? Recovery?

Where the heck is GR or someone that didn't lose brain cells early in life.