Click on top engine

I agree Warren but if ticking then it's "tinging", which means Tight spot not Loose. Majority of the time it's built-up cruddy oil that has stuck to the bore where follower/bucket goes or a "normally exhaust" side bucket that poses the problems. They can slightly become oval/warp with enough heat. Wasn't talking about the shim to bucket, talking about bucket to bore in head. A ticking sound isn't a result of starved shell bearings, that's a whole different sound, a squeal. Although they are closely related, no oiling. All in all, if it's ticking caused by a sticky bucket when cam is transitioning from heel to lobe this can cause some interesting expenditures. I have plenty of examples, believe me. Even happens on the Longevity proven KLR650's. Exhaust cams are internal oiled with a bridge crossover between Intake and Exhaust cams. They share the Exact same buckets, shim over. BUT, because the RH side of the Exhaust camshaft is the last one to get feed dino, they spit the shim because the bucket welds itself to the bucket bore and subsequent fling of shim right thru the head. I've plenty of examples!    

What I think is happening is the lack of lube to the bucket bore has caused the bore to wear as ally will loose to steel every time. As heat builds the bucket does swell at mid height causing a slightly "barrel" shape.  The widest part of the "barrel" is acting as a rocker and the rear bottom half is slapping the bore as the lobe contacts the shim and the as the lobe pushes the bucket down it gets to the center point and then releases the pressure which then allows the bucket to pivot on its waist bulge and the top front half slaps the front of the  bore under the valve spring pressure.
So effectively the bucket is rocking in the bore............ 

Maybe, hehe 🤷

Hello all,

sorry to be late on my posts but i have worked on it.
I check all, completely remove the top cyclinder and piston clean all passages, check the valves, check or replace the oil valve seals, shims on spec, check the buckets for wear, carb sync, the exhaust leaks, check the oil pump.

Tested and click is always here.

I try to put oil direcly on the cams and the click disappear at start.
I check then on center stand if oil is on the buckets. 
It's normal to don't have oil on the 4 center buckets because oil go back to the center of the engine by a hole.
Number 1 exh and 4 exh have oil.
Number 1 int have oil. But no oil stay or come on the number 4 int.
This one stay dry.
Where is coming the oil on this one?
I put air pressure on the 3 to 4 int and passage is ok
I put air pressure on the 2 small holes under the cam too (bushings holes)

Where to check now ?



 

Are your cam bearings OEM or aftermarket (OEM have a tapered hole whereas many aftermarket have a square edge on the oil hole which can restrict oil flow)

On all the cam bearings, oil is pumped up through the little hole in the lower cam shell. As the cam spins it seeps out from the shell cam / interface and fills the recess the bucket sits in.
So if you have oil around all the buckets except no 4 inlet then oil must be getting through as it has to pass no 4 to get to no 3. 
So your issue is definately one of two things. 
1. Cam shells, the lower shell has a hole in it which lines up with the hole in the carrier. If it doesn't line up or doesn't have a hole then no oil can pass to the cam/shell interface. 
2 the cam cap is too tight and is pushing the cam down so tightly that the cam is effectively block the oil feed from the shell. 
Plastigauge will test the tight cam cap theory. 
If it is too tight a simple method to see if it were looser would fix it is to make a shim from a coke can that siits under the cap before bolting down. For info a coke can is only 100 microns thick. 
Once you determine the reason for oil starvation to that cap we can advise the best fix.

Edit, just had another thought. 
I have seem after market cam shells where only one of the pair has a hole in it. So if they have been fitted with the holed shell half in the cap and the solid half in the head then the oil passage will be blocked. 

"to make a shim from a coke can that siits under the cap before bolting down"
you mean "4 small washers with a hole to place under the cap" where the screws are bolt ?

Thank you

Cut a square the same size as the cam cap "foot' with a bolt hole centrally.
Put them under the cap on the carb side only first then bolt the cap down. Doing one side only will ease the cap /cam clearance only 50 microns. 
Check the clearance this generates using plastigauge. 
If it's still not sufficient do the other side of the cap aswell which will lift the cap 100 microns. 
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