Bob is the oil guy forum is not the forum it used to be. They have been taken over by the liberal crowd and now everything is politically correct. Example they are now more like a cult and you had better be running the latest API spec or else.
Here is an example, when the API started requiring the oil companies to use less ZDDP (Phosphorus and zinc) older flat tappet style cam engines started having cam and lifter failure.
Now remember that according to the API each new spec is supposed to be backwards compatible but that does not always work out so well and when you are one of the ones who suffers a cam/lifter failure you are also the one stuck paying the bill to rebuild the engine.
Not every flat tappet cam/lifter style engine will fail with reduced ZDDP, but many will fail so you are pretty much flipping a coin and taking a chance, or you can source an oil that still contains a minimum of 1200 PPM (Parts Per Million) of ZDDP and not have to worry is your flat tappet cam/lifter going to fail at some point or will you be one of the lucky ones.
The reason I bring this up is because the Yamaha V-Twin in several Yamaha models including the new Star Venture and Eluder use a flat tappet style cam and lifter. There have been some documented cases of cam/lifter failure on this engine.
Many years ago engineers learned that ZDDP was a great additive to protect flat tappet cams/lifters, as the engine heats up and runs the ZDDP builds up a coating of ZDDP on the metal parts. This is the important part, most of your engines wear occurs at start up before the oil is flowing and providing protection. ZDDP is a sacrificial coating meaning that when you start the engine the ZDDP is providing protection and is being worn away until the oil pressure/flow takes over protecting the metal parts.
Without a protective sacrificial coating like ZDDP you have metal to metal contact that is wearing the metal surface of the parts like the cam lobe and lifter bottom and lifter sides as well. Once the metal surface of the cam lobe and or lifter start to wear that is where you get the failure.
These newer oils rarely have to deal with flat tappet cam/lifter systems because most modern engines are one of the following, overhead cam much less pressure on the cam lobe, roller lifter again much less pressure on the cam lobe.
The flat tappet cam in block pushrod activated system creates much more pressure on the cam lobe and bottom of the lifter, hence why ZDDP became popular in oils, it's protective sacrificial benefits. Now the new spec oils have reduced ZDDP and they want to completely remove ZDDP and have replaced the ZDDP with other high pressure additives, the problem is these new high pressure additives do not provide a sacrificial coating like ZDDP does so when you start up your engine with these new oils you are back to metal on metal until the oil pressure builds up, hence the reason there was a rash of flat tappet cam and lifter failures when the first oils with reduced ZDDP came out. Remember that overhead cam and roller lifter style valve trains are not effected by the removal of the ZDDP it is only flat tappet style valve trains that are still effected.
This is where I have issue with Bob is the oil guy forum, they will push the new oils as the be all end all of motor oils ignoring those with flat tappet cam engines.
One more example of why ZDDP is important to flat tappet engines, a race team was buying their engines from Roush Racing, one of the top performance engine builders in the world. Today known as Roush/Yates as Roush and Yates merged their engine building businesses.
That race team all of the sudden started having cam and lifter failures, they could not make a cam or lifter live for any length of time. They got with Roush Racing and presented them with their problem, they were using the same oil Roush was which was Valvoline at the time who was also a Roush sponsor on his race cars. Both the team who discovered the problem and Roush were stumped and finally Roush Racing contacted Valvoline and discovered that Valvoline had changed the formula of their racing oil changing the amount of ZDDP in it.
In the end Valvoline working with Roush Racing changed the formula to include the original amount of ZDDP and the cam lifter problem was solved.
Professional engine builders of flat tappet style engines recommend from 1200 PPM to 1500 PPM of ZDDP depending on the engine builder. The new API specs allow no more than around 800 PPM of ZDDP, I don't know what the new SN+ API spec allows.
High performance engines will not last with ZDDP level at 800 PPM because the valve spring pressures are just too high and will damage the cam lobe/lifter.
A stock engine will have a much better chance of not being damaged but some will suffer damage and it will be on your dime once out of warranty.
Now what makes the Yamaha V-Twin susceptible to cam lobe lifter damage is like a high performance engine that runs high valve spring pressures this Yamaha design is using one rocker arm to operate two valves and valve springs, so you don't have the pressure of one valve spring on the cam lobe lifter, you have the pressure of two valve springs upon the single cam lobe and lifer because these engines are a four valve cylinder head design operated by a cam in block push rod flat tappet design.
What you have is one cam lobe operating one lifter and push rod that operates one rocker arm that is operating two valves at the same time creating more pressure on the cam lobe and bottom of the lifter which is why the ZDDP is so important every time you start this engine.
Having said that the choice is yours run what ever oil you want, for me I will stick with Redline oils in all my vehicles because Redline has plenty of ZDDP in it to protect the engine at start up.