dura ace block?

[ivanooze]

-so i'm a fan of GCN, in their recent video they mentioned something about a "dura ace block" in which you can put a 7 speed wheel onto a dura ace di2 rear derailleur

-my question is this. how did they do it? i'm assuming you would need a 7 speed compatible rear wheel or if you have the freehub body on the wheel that's a 10 speed then i would assume that you can just put a bunch of washers to fill up the space and turn that 10 speed hub into a 7 speed right?

here's the picture on instagram
https://www.instagram.com/p/9qP8T6kM2r/?taken-by=globalcyclingnetwork

[goonster]

I'm no expert, but that looks like a freewheel on reg'lar threaded hub.

[jischr]

I don't understand why anyone would want to retro from 10 to 7, but I ran a 10 spd cassette on a 7 spd hub for 3 years with a 10 spd brifter. The stack heights aren't that different.

[ultraman6970]

Thats an old wheel... is not like they just put a 7 speed cassette in there.

If it works, great for shimano, the problem is that nobody is using straight blocks so small now a days hehe :) at least not racers.

To me this is an invention somebody came up with, fake.

[ivanooze]

I don't understand why anyone would want to retro from 10 to 7, but I ran a 10 spd cassette on a 7 spd hub for 3 years with a 10 spd brifter. The stack heights aren't that different.

the only reason i want to do this is because i have a colnago 6 or 7 speed ( i forget) and all i have is a 10 speed rear wheel hub, so instead of buying a new wheel for it, i'd much rather just try and convert my current wheelset. the width of the 10 speed wheel should fit a 7 speed dropout

[ivanooze]

you're probably right about it being a threaded cassette, i dont know any 7 speed cassettes that aren't threaded

[ultraman6970]

7 speed shimano cassettes?? yes they had... and they had 7 speed freewheels too.

[fogrider]

7 speed shimano cassettes?? yes they had... and they had 7 speed freewheels too.

Yeah, 7 speed cassette was the first, I still have mine and it's still a smooth running wheel!

[ultraman6970]

Hyperglide I think was called, same year that shimano Double pivot brakes started to show up in the market. Just a revelation to use those brakes I remember. Shimano put their feet into campy territory back those days, a lot of innovations.

[jc031699]

the only reason i want to do this is because i have a colnago 6 or 7 speed ( i forget) and all i have is a 10 speed rear wheel hub, so instead of buying a new wheel for it, i'd much rather just try and convert my current wheelset. the width of the 10 speed wheel should fit a 7 speed dropout

You can run a 7spd cassette on a 10spd hub with a 4.5mm spacer behind the largest cog.

http://www.sheldonbrown.com/k7-7.shtml

Your Colnago may have 126mm rear spacing, but if steel, can be pulled open to fit a 130mm spaced 10 spd hub without much difficulty.

[jc031699]

7 speed shimano cassettes?? yes they had... and they had 7 speed freewheels too.

I have a whole drawer full of 7 spd cassettes. Let me know if you are interested.

[oldpotatoe]

the only reason i want to do this is because i have a colnago 6 or 7 speed ( i forget) and all i have is a 10 speed rear wheel hub, so instead of buying a new wheel for it, i'd much rather just try and convert my current wheelset. the width of the 10 speed wheel should fit a 7 speed dropout

If they are both 130mm..take the 10s wheel, add spacers so the 7 or 8s cogset will go on and lockring will tighten. Use loose cogs and 10s spacers of some type(like shimano)..adjust rear der-go ride.

[ivanooze]

sorry about the 7 speed confusion. it's actually a 6 speed so... yeah...