VALVE ADJUSTMENT PROCEDURE FOR
THE YAMAHA XS1100
The information provided here is for informational purposes only and is no substitute for the proper factory repair manual. If you use the information provided here, you do so at your own risk.
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I used the Motion Pro tool to remove the valve shims. Several people claim that this tool will not work. With a bit of modification I was able to use it successfully. Minor grinding on the bottom of the tool that sits on the valve cover mating surface and it works fine. The grinding allows the tool to sit lower and contact the valve bucket. I also had to elongate one hole so it would line up better on the valve buckets.
First, a bit of an explanation on the valve shims. Valve clearance on the XS1100 is adjusted by using shims of different thickness. Increasing or decreasing the thickness of the valve shim decreases or increases the clearance between the camshaft and the shim, which sits on top of the valve bucket. Valve clearance is important for the proper running and performance of any engine. Too little clearance and there is a chance the valve won't close properly, possibly resulting in a burnt valve or valve seat. Too much clearance can result in excessive valve noise and the engine not "breathing" properly due to the valve not opening fully.
First thing to do of course is remove enough components to allow access to the camshafts and valve buckets. Usually removing the seat, fuel tank and valve cover is sufficient. You will notice there is a lot more removed in this picture then is necessary. The next step is to remove the timing cover located at the left end of the crankshaft. Rotate the crankshaft so that the lobe on the camshaft is pointing away from the valve bucket. Insert a metric feeler gauge between the camshaft and valve bucket. Yamaha factory manual indicates the exhaust valve clearance to be 0.21-0.25mm(0.008-0.010in) and the intake valve clearance should be 0.16-0.20mm(0.006-0.008in), both measurements are taken when the engine is cold. The highest number gauge that will fit between the camshaft and valve bucket indicates the valve clearance. A slight drag should be felt when moving the gauge in and out. Record this measurement. Once you have ascertained the clearance, the next step is to rotate the valve bucket so the notch in it is accessible to you. This notch is used to remove the valve shim. Then rotate the crankshaft so that the camshaft lobe is depressing the valve bucket. Install the Motion Pro tool, then rotate the crankshaft to allow the tool to hold the valve bucket depressed. BE CAREFUL HERE!! Make sure you rotate the cam lobe AWAY from the tool. If not, then you risk damage to camshaft or cylinder head. Remove the valve shim by first inserting a small screwdriver into the notch and then forcing the shim away from the valve bucket. This may take some force as the oil between the shim and valve bucket creates a bond that is difficult to break. Once you have the shim loose, then remove it from the valve bucket. Measure the thickness of the valve shim, and record the size. I made a chart to keep a record of valve clearance and shim size. The size is printed on the shim, but is not always legible. Next, cross reference the valve clearance and current shim thickness with the chart provided in the manual or provided here. These charts will tell you what shims you need in order to achieve proper valve clearance. Repeat this process for each valve. When re-installing the shims, make sure you put the side that has the size stamped on it facing the valve bucket. This will help keep it legible the next time you have to adjust the valves. Shims are available at the dealer. Quite often, proper clearance can be obtained by swapping shims from valve to valve, resulting in only needing to purchase 1 or 2, instead of 5 or 6. When re-installing the valve cover, ensure that both mating surfaces are clean of old gasket material and don't have any gouges or nicks in them. Always use a new gasket, never try to reuse the old one.
Questions or comments?