Shimano 8 speed STI's

afcbian

I have bought my son a bargain beginners bike but it's got the old style 7 speed bar mounted gear shifters.
I want to put 8 speed STI's on for him
My question is does anyone know if the back wheel is likely to take an 8 speed cassette in lieu of the current 7 speed or is it a case of changing the back wheel too ?
Any advice welcomed
Thanks
Ian

ugo.santalucia

Do you know if it is a freewheel system or a freehub + cassette system currently?

drlodge

8 Speed shifters should work OK with a 7 speed cassette, since the spacing is pretty much the same.

afcbian

Thanks guys