I think the reason seems to be that the new HG70's are slightly narrower spaced that before as 8sp spacing is now the 'standard' if you like.
I have tried to measure with a micrometer to determine if this is the case but can't get a consistent and tangible difference (it's close enough that 8sp shifters with 7sp blocks and vice-versa work fine).
I therefore assume that maybe the actual cogs are stamped from a narrower sheet of metal (good for weight, the enviroment and profits, how clever!) though I have not had a new 7sp freehub body to compare to see if this is true but it CANNOT be wear related surely!?
Until I am sufficiently bored to do an OU degree in engineering and use this for my thesis I am happy to add one wibbly washer!
Has anyone else noticed this, does anyone else care? Should I section myself? Does Sheldon Brown know?
OH! Yes, I think the cassette on Miss Kona is 11-28, I definately did that mod!
Somerset, like 'Heartbeat' with newer cars!
Retro MTB: 1992 Cannondale 3.0 Deore XT M730. 1992 Marin Pine Mountain Deore DX M650.
Retro road: 1992 Eddy Merckx Corsa Extra Telekom Shimano 600 STI. 1993 Dyna Tech Ti.
Modern: 2006 Wilier scandium Ultegra 6600. 2014 Wilier GTR Ultegra 6800.