V-Power Vs Standard

I have tried high octane fuels in performane cars and big 4X4's (V8's)
- doesn't make a blind bit of difference to performance or mpg.
Save your money - I wasted a bit of money by buying this stuff for about a month and reverted to normal 97 RON.

Shell V-Power is good for keeping the inside of the engine clean from carbon deposits that over time build up and can cause a drop in power.

it's the same for other premium fuels like BP's Ultimate.

They don't give you any more performance but they help keep your machine healthy. There's a video for Shell V Power's cleaning attributes on Youtube. http://www.youtube.com/watch?v=iU35MkEThG0

I have found that shell fuel is the best to use in the bikes. Get an extra 40 miles from the XJ6 just from changing from the supermarket stuff.
The supermarkets fuel has more ethanol in it and this can cause some bikes to run sloppy, it is also alot cheaper to prduce.
I know the Senna isn't happy unless it is running the better fuels, I have tried this at several garages to make sure it wasn't the dregs of the tank when filling up. It means a more expensive bill but there is definetley a difference in performance.
I think fifth gear did a feature a few years back, proving that unless you have a £180k+ supercar you wont really notice the difference. I'd imagine the same applies with more powerful bikes.

Most machines are tuned for 95RON or below. The additional octane will not boost power but may increase fuel economy ( I did a trial in my old mini a few years back and got a slight increase in economy - not a lot though).

The only advantage to the super unleaded fuels is that currently many do not contain ethanol. All premium fuels (including shell I'm afraid) are currently E5 (EU bull meaning we have 5% ethanol in the fuel). This will go up to 10% soon.... so be aware, many older bike and cars will suffer. Older bikes will run a bit better on super because they were set up for leaded and/or E0 fuel. The big difference is that the fuel will withstand a higher pressure before self detonating, hence the use in high boost turbo cars.