This has already been beaten to death innumerable times.
In a low compression engine, like the TW, there is no benefit to using any gas with higher octane rating than regular 87. Higher octane does not mean better - it means there are additives in the gas to prevent pre-ignition inside the cylinders of a high compression engine, they make the gas burn slower, and use of that gas in our engines actually produces less power and poorer overall performance and also will drain your wallet faster.
If your engine knocks or pings with regular gas and you use premium to prevent that, you are masking a problem with your engine, it is not the gas that's causing that, and in the long term if you don't correct the problem, it will cost you.
There is no benefit and no reason to use high octane fuel in the TW and Yamaha recommends regular gas, if you read the owner's manual.
