Most people don't know when standards for oils have been changed, in the automotive world the API lowered the amount of Phosphorus and Zinc that can be in the oil several years ago, that is not a problem if you are running a modern engine as most engines today are roller cam style valve trains or they are overhead cam style valve trains both of which do not put the same friction load on the valve train as a flat tappet cam/valve train does. We all know that there were many cam/lifter failures when people used the new API spec oils in flat tappet style engines, while not every flat tappet engine will suffer a cam/lifter failure there were still many that did fail. The cam lobe and lifter contact point is one of the worst lubricated areas in an engine because they are exposed yet they are also the highest load bearing friction point in the engine. It is no wonder so many flat tappet cam/lifters failed when using the newer API spec oils with Phosphorus and Zinc levels reduced down to 800 to 1200 PPM. It is recommended that a flat tappet style cam/lifter have at least 1500 PPM of Phosphorus and Zinc for proper protection. The oil companies say that as long as the older flat tappet engines have stock valve springs in them they should be protected, but if you have a performance or heavy duty valve spring than the API spec of 800 PPM to 1200 PPM of Phosphorus and Zinc is not adequate and can/will lead to flat tappet cam and lifter failure. In 2016 JASO the Japanese standard used for motorcycle oils changed their specs lowering the amount of Phosphorus and Zinc down to 800 PPM to 1200 PPM, again on must modern motorcycle engines this won't pose a problem because they are overhead cam style valve trains and the load friction will tolerate the reduced Phosphorus and Zinc levels in the new JASO standard. The problem comes in on those motorcycle engines that use a flat tappet style cam and valve train, one such motorcycle is the new 2018 Yamaha Star Venture and Eluder motorcycles with the revised 1854 CC V-Twin engines. These engines are using a flat tappet style cam/lifter valve train so the load friction is greater than overhead cam style valve trains. This should be a concern because the reduced Phosphorus and Zinc levels may result in cam/lifter failure in this engine. There are three documented cases of cam/lifter failure with this new Yamaha 1854 CC V-Twin already, how many more there may be is unknown unless the owner posts to a website to document the failure. Of those three one suffered cam/lifter wear failure by the 3,400 mile mark, the second cam/lifter wear failure was between 7,000 miles and 8,000 miles and the third failure the mileage is not known except that it was under 7,000 miles when that cam/lifter wear failure occurred. The engine that failed between the 7,000 and 8,000 mile mark was documented as using Yamalube 10w-40 conventional oil up to the failure. The other two engines it is unknown what oil they where using when the failure occurred. The Yamaha 1854 CC V-Twin uses a flat tappet style cam/lifter valve train and one cam lobe, one lifter, one push rod and one rocker arm operating two valves and two valve springs on the four valve heads, that increases the load friction placed upon the cam lobe and lifter. With the reduced Phosphorus and Zinc of between 800 PPM and 1200 PPM in the JASO certified oils from 2016 forward I am of the opinion that the reduced Phosphorus and Zinc (ZDDP) is the cause of these early cam/lifter load wear failures on those three engines. I own a 2018 Yamaha Star Venture with the 1854 CC V-Twin but after the break-in period (first 1,000 miles per manual) I changed out the Yamalube 10w-40 conventional oil to full synthetic oil, the first synthetic oil I used was a short run on Redline 20w-50 to continue flushing out the wear in metals and then changed to Yamalube 15w-50 full synthetic with ester and ran that oil to the 4,000 mile service where I switched over to Redline 10w-40 synthetic oil and have run the 10w-40 Redline motorcycle oil since. My used oil reports have come back showing good wear numbers with Phosphorus and Zinc over 1500 PPM which is the recommended minimum amount of Phosphorus and Zinc to protect a flat tappet style cam and valve train that is high performance. Knowing this cam/lifter/push rod/rocker arm has to operate two valves and two valve springs on the four valve heads I feel that would be equivalent to a high performance or heavy duty valve spring. This is just a heads up about the new JASO standard that reduced the amount of Phosphorus and Zinc to 800 PPM to 1200 PPM in the new 2016 JASO standard in case you are running an engine with a flat tappet style cam/valve train. You may want to look for a motorcycle oil that has more Phosphorus and Zinc than the 2016 JASO standard allows to protect that flat tappet cam and valve train. You will have to check the specs of the oil you are interested in, I am running Redline Synthetic 10w-40 motorcycle oil because the specs show it has an average of 2100 PPM of Phosphorus and 2125 PPM of Zinc, both more than sufficient to protect a flat tappet style valve train.