Hi
Changing it over to full 17 inch wheels but been advised to go with 120/70/17 on the front instead of 120/60/17 as will improve cornering performance.
Not convinced can anyone advise

If you're using 17 inch wheels then you'll be going to be on supercorsas..and they come in 120/70.

I cannot tell the difference..it is certainly at least as good as 120/60.so don't worry about it!!

Good guess
It handles really well on hot BT090 can't wait to try super corsas

I can only speak from experience of the R6. OE front was 120/60 and it was bog awful to turn. Changed to a 120/70 and it improved flickability no end.

I'd go 120/70 every time.

Oh, I can recommend the Supercorsa very highly too - I've just had a pair fitted to the Sprint. So much feedback and they are permanently planted. It's reminded me why I love tyres from the big P