Valve clearance fudge factor
#1
Valve clearance fudge factor
My 2009 is approaching 17000 miles. I have not yet checked the 15000 mile valve clearance, I did check it at 8000 miles and had to buy 2 shims and move some around at that time. Is there any consensus as to how much leeway is reasonable as to miles between checks? How far can I push it? 2-3k miles? What are the symptoms of pushing too far? Easier than running a compression check.
Last edited by snappster; 06-22-2017 at 08:48 PM.
#2
No not really. Too many factors. Air filter changes , fuel quality, RPM run ect. By the time you have symptoms you could have a burnt valve. Usually hot hard starting is first symptom of tight valves. I would check your valves. It's time.
Last edited by s10gto; 06-23-2017 at 01:02 AM.
#3
Valve clearance is checked and the values were a bit unexpected. Cam drive side of both cams has high clearance, opposite side is just slightly tighter than the mid point in the range of acceptable values. In fact, I plan to leave the shims opposite the drive sprockets alone. The drive side intake is going to the drive side exhaust and one new 3.00 shim will go to the intake next to the cam drive. This works out to 0.05mm thicker shims for both cams' drive side. I ordered that shim today so no riding for a few days. Anybody ever seen the cam cap to cam journal clearance go high, like above the service limit of 0.0059" ? I better get some plastigage and find out where I am. I had previously thought cam drive chain forces would dominate/cause wear but having pulled the cams today I now think the valve spring force upwards against the cam lumps is the predominant force causing wear between the cam journals and the cap. But why is it worse on the cam drive side?
Last edited by snappster; 06-24-2017 at 09:22 PM.
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