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Compression check

I bought this thing used with 12k miles on it and it had a big bore kit installed by HD bringing it up to 95 ci. The cams are stock to my knowledge, unless different cams come with the kit. The previous owner paid $659 for the kit plus labor. But the engine never made any unusual noises until the last year or so, so I know it shouldn't be sounding like this. For you old timers like me, it sounds just like the old v8 engines with solid lifters that need adjusting. Just a lot of clicking that is in sync with the rpm. I replaced the lifters and have adjustable pushrods that have been adjusted numerous times, and nothing stops the noise. I've replaced the cam chain tensioner shoes and new cam bearings. Numerous mechanics have listened to it , and noone can pinpoint the cause without going into the engine, and I can't really afford hours of labor at this time, especially since the darn thing runs fine, except for the noise. I'm driving my wife crazy with this! Oh well, maybe I could win the Powerball and buy a new Harley, or a couple of them. Ha Ha, in my dreams.
 
I bought this thing used with 12k miles on it and it had a big bore kit installed by HD bringing it up to 95 ci. The cams are stock to my knowledge, unless different cams come with the kit. The previous owner paid $659 for the kit plus labor. But the engine never made any unusual noises until the last year or so, so I know it shouldn't be sounding like this. For you old timers like me, it sounds just like the old v8 engines with solid lifters that need adjusting. Just a lot of clicking that is in sync with the rpm. I replaced the lifters and have adjustable pushrods that have been adjusted numerous times, and nothing stops the noise. I've replaced the cam chain tensioner shoes and new cam bearings. Numerous mechanics have listened to it , and noone can pinpoint the cause without going into the engine, and I can't really afford hours of labor at this time, especially since the darn thing runs fine, except for the noise. I'm driving my wife crazy with this! Oh well, maybe I could win the Powerball and buy a new Harley, or a couple of them. Ha Ha, in my dreams.

Have you had the rocker arms and supports checked, the pad contacts do wear or do you have rollers?
 
The oil pressure gage on the dash shows 10-20 psi at idle and 32 psi at 2000rpm and above. How else can I check the pressure?
 
Since I have near zero trust in HD gauges,, I would go ahead and check the pressure using a mechanical gauge at the oil sending unit port.

I know you said you changed the lifters. But did you hear any difference in noise after changing the lifters.?

What calculated distance (number of push rod adjustment flats vs thread pitch) beyond zero lash are you running. And your absolutely sure your adjusting valve lash at TDC of compression stroke and not TDC of valve overlap? Other than the noise,, the engine idles and runs smooth?
 
Thanks for all the replies, this sure is a great forum. I'm getting alot of noise from the front cyl area like tappets, but it isn't tappets cause I had the rocker box cover off and checked everything. Adjusted the push rods numerous times and replaced the lifters. Still the same old noise. I had a mech listen to it and he said I should check compression. So I'll try it. New cam chain tensioner shoes and cam bearings too. The bike seeems to run fine, but the noisy engine is driving me nutso. Some friends said to just turn the radio up, and don't worry about it...

Here is the line in the sand. All mechanical work done here, NO NOISE(unusual)
*****************************************************
other side of line now; Noise started here????

lifters replaced and the push rods adjusted like HOOPLE asked???

I had a clicking from my front end like you state and it turned out to be where the pushrods were *rubbing and *catching in the outside cover tube.

Have you checked the **STARIGHTNESS of the pushrods when in position to spin them (cams in Off valve pressure)..

Could the problem be a Cracked or Broken valve rocker support in that front head.... Someone mentioned this a while back and it WAS the problem.

Also Have you put it on a stand with plugs out and turning the engine over with tire and tranny in 5 gear...

Is the sound (test with a stethoscope) ONLY in the front head or LOWER???

As for the oil pressure,,,, it sound good enough on the HD gauge to Not cause the noise.. I agree with Hoople , too many false readings reported with HD gauges but if it has the oil?

Sounds in our bikes can be hard to find, traveling many directions and sounding here No Here no etc " ".. and the listening devices are needed, try these suggestions and get back here with the results.
If the noise started after mechanical work was done HMMMMmmmm
signed....BUBBIE
 
Bubbie and Hoople and everyone else thanks again for all the advice. I did have the bike up on a jack and spun the rear wheel to get to TDC on the compression stroke. Then with zero lash I turned the Screaming Eagle pushrods 2 1/2 turns. Then I tried 3 turns. Then I tried one turn. No difference. I checked to see if there was any rubbing on the tubes, nothing. With the naked ear the sound is coming from the front rocker box area. With the stethescope it sounds the same both at the rocker box and the camshaft area. Like you said, noises are hard to pinpoint. I think I'm finally giving up and going to fork over some cash to a real mechanic and see what he can find. My wife is getting more fed up with this than me I think. She keeps telling me to take it to a mech. And she usually is right!
 
Bubbie and Hoople and everyone else thanks again for all the advice. I did have the bike up on a jack and spun the rear wheel to get to TDC on the compression stroke. Then with zero lash I turned the Screaming Eagle pushrods 2 1/2 turns. Then I tried 3 turns. Then I tried one turn. No difference. I checked to see if there was any rubbing on the tubes, nothing. With the naked ear the sound is coming from the front rocker box area. With the stethescope it sounds the same both at the rocker box and the camshaft area. Like you said, noises are hard to pinpoint. I think I'm finally giving up and going to fork over some cash to a real mechanic and see what he can find. My wife is getting more fed up with this than me I think. She keeps telling me to take it to a mech. And she usually is right!

ONE MORE STAB at this;

Have you switched oils to a different brand and type or weight???? over the increase of this Noise???

IF you have ??? answer what and weight...

I would suggest MOBIL V-1 fully synthetic 20w/50 for the fact (i don't use it in my bike) but IT is thicker or seems to be and SEE IF that makes a difference in the TAP tap tap..

signed....BUBBIE
 
If you can find an aircraft mechanic with a diffrerentail type copression tester you can get an idea if it's rings or valve problems with the jug. May have to take and old spark plug and make up the addapter.

Hey CromeDome, could you elaborate what signs point to which failure mode?

Thanks, could be good info for any future problems.
 
dd; You have checked and explained a lot of things. In post #13, Jack asked about the rocker arms and supports. It's possible the rocker arm to shaft clearance is out of spec. either end play or shaft to arm.
I understand your frustration and being ready to take it to a mech., but be careful. Many mechanics will just throw parts at it hoping to hit the cause.
 
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