The other day i was riding and the quad died. When i kicked it back over it made a grinding noise and the valves were clicking. I took it home took all the plastic and gastank off. Then took the left sidecase off and lined the flywheel up to make the piston on top dead center. Then i adjusted the valves and tightened the cam chain. The grinding is gone but the valves still click. Just for the heck of it i've played around with the adjusters (tighting them up quite a bit) to see if i could the valves to stop clicking and they won't. Went back and did it again the right way ( with the feeler gauge) and it still clicks. I can't adjust it out. Anybody got any ideas on what it could be?

 

Careful; if set too tight, the valves are likely to burn. Proper clearance gives valves time to transfer heat to the head through the valve seat.

Some valve noise is normal, if excessive, your noise could be from valve guide/stem wear.

Diogenes

 

You said you had the piston at TDC. Was it on the compression stroke or on the exhaust stroke? Check again to be sure you were on the compression stroke before checking the clearance. If on TDC of the compression stroke, the tappets should be open.

 

Respectfully begging to differ, Hot_Shoe_CV; at the top of the compression stroke, both intake and exhaust valves are totally CLOSED, not open.

I find the compression stroke by removing the sparkplug and feeling for air rushing from the hole when I pull the starter cord.

Diogenes

 

If you were TDC on the end of the exhaust/start of the intake stroke, you could tighten the valves to zero lash, and they would still rattle. They need to be set at TDC of the compression stroke. Turn the engine by hand with your finger over the spark plug hole. When air quits pushing past your finger, it should be near TDC. Line up the timing marks & re-check the valve clearance.
What worries me is this started with a grinding noise. Makes me wonder if a cam lobe/lifter didn't get a rough spot or possibly a valve guide go bad. A little tick is not a big worry, but a 'clak, clak, clak' may be reason for concern.

 

Diogenes,
Well, that's what I always understood, but I checked the shop manual for my Raptor before posting & it said that clearance should be present at TDC on compression & if closed to rotate crank counterclockwise to next TDC. I'm taking my ride to the dealer to day for an initial valve check..I'll try to verify the manual's info.
P.S. After further checking in a Suzuki manual it explains it more clearly...when the tappets have clearance, it indicates that the VALVES are fully closed & piston is at TDC. Hope this clears up the semantics for Bermbanger.

 

Well the top end was rebulit about 10 tanks of gas ago so the valves and stems should be good. I'm going to take the cam cover off and check out the cam and put a new gasket on since its leaking. I'm still a little confused on the tdc thing. All my clymer book says to do is line up the flywheel and make sure the rocker arms have freeplay.

 

Alright i took the cover off and inspected everything. The cam and rocker arms look great and the chain is tight. I put it back together with some yamabond. Tomorrow i'll take the sidecase back off and readjust the valves. When my flywheel is lined up both valve adjustments are up really high. So that would mean the camshaft lobes down Meaning both valves open. Right? I didn't think both valves were open at the same time.They've got to be open if the stem is up toward the top of the valve adjustment cap.

 

bermbanger,
Once again, if there is clearance in the rocker arms/tappets when piston is TDC, the piston is on the compression stroke and the valves are closed. Assuming you already know adjustment is done on a cold engine.

 

Well i finally got it fixed. I set the valves then played around with the cam chain adjuster and finally no more noises. Or atleast no more clack clack just a tiny click click. It runs like a raped ape so i'm not touching the valves for a while.