Valve clearances
09-13-2011, 06:21 PM
#1
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Join Date: May 2011
Location: Jacksonville,fl
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Valve clearances
i have a wired question.. i have a paint can sound in my engine and i took the rear cover off because that is the one i suspect is causing the problem. i went to check my valve clearances and on the intake and exhaust i cant get the minimum in between the cam and cup. if the valves are bent could that cause it or could to tight of shims cause the rattle in the engine? i am lost and not sure what to do. i dont want to take my heads off for no reason. i am also wondering could i have broken a spring retainer?
any ideas?
any ideas?
09-13-2011, 09:52 PM
#2
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Join Date: Aug 2007
Location: Lake View Terrace, CA
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Well keep going smaller on the feeler gauge until something does fit.....
If the clearances are tight enough you might be getting a valve to stick open a bit after the engine warms up.
So the first step is set the clearances to spec before you do anything else....IMHO
If the clearances are tight enough you might be getting a valve to stick open a bit after the engine warms up.
So the first step is set the clearances to spec before you do anything else....IMHO
09-13-2011, 11:11 PM
#4
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Join Date: May 2008
Location: San Clemente, CA
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With bent valves you'd have low compression and loss of power. Your bike wouldn't be running well.
"Paint can sound", to me, means not a rhythmic noise, but random. If it's happening only during acceleration, it's most likely detonation, possibly due to carbon deposits in the combustion chambers. But if the sound is rhythmic (tap..tap..tap), and you hear it at idle, you most likely need to adjust the valves.
Also, double check to make sure that the cams are in the right position when you check valve lash. Do you have experience with valve adjustment? I've found many with little experience are checking lash with the cams in the wrong position.
I personally ignore the timing marks and put each cam in position where the lobe is pointing 180 degrees away from the lifter when checking lash. Of course you wouldn't want to remove the cams in that position... that would be bad. You need to follow the manual to remove the cams.
"Paint can sound", to me, means not a rhythmic noise, but random. If it's happening only during acceleration, it's most likely detonation, possibly due to carbon deposits in the combustion chambers. But if the sound is rhythmic (tap..tap..tap), and you hear it at idle, you most likely need to adjust the valves.
Also, double check to make sure that the cams are in the right position when you check valve lash. Do you have experience with valve adjustment? I've found many with little experience are checking lash with the cams in the wrong position.
I personally ignore the timing marks and put each cam in position where the lobe is pointing 180 degrees away from the lifter when checking lash. Of course you wouldn't want to remove the cams in that position... that would be bad. You need to follow the manual to remove the cams.
Last edited by VTRsurfer; 09-13-2011 at 11:22 PM.
09-14-2011, 04:01 AM
#5
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Join Date: May 2011
Location: Jacksonville,fl
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i have checked them in the lobe up position and on the exhaust for example i can get .020 to go in tight. i think the limit is .028 for low side.
the noise i am having is at idle. is a tick tick sound.
when i accelerate it turns into a paint can. i know the sound i am hearing is valve related based on my experience with cars.
with this bike I am unsure of how it works and what could be making it do it.
This all started when the CCT broke on me(it was caught before it got too bad) but my rear cylinder went out of time and figured something got bent but my valve clearances are on the low side not the high side. Could I have broken a spring maybe? All I know is that the clearances are tight as hell so need less to say the dumb *** that supposedly did the valve job before I got it F’ed it up
I think since it has 62k on it, it may be time for a head job and just replace everything. I priced it out and with valve seat being ground at a machine shop and all new valve components will run me just over 500.00.
Does that sound about right?
the noise i am having is at idle. is a tick tick sound.
when i accelerate it turns into a paint can. i know the sound i am hearing is valve related based on my experience with cars.
with this bike I am unsure of how it works and what could be making it do it.
This all started when the CCT broke on me(it was caught before it got too bad) but my rear cylinder went out of time and figured something got bent but my valve clearances are on the low side not the high side. Could I have broken a spring maybe? All I know is that the clearances are tight as hell so need less to say the dumb *** that supposedly did the valve job before I got it F’ed it up
I think since it has 62k on it, it may be time for a head job and just replace everything. I priced it out and with valve seat being ground at a machine shop and all new valve components will run me just over 500.00.
Does that sound about right?
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