Which Groupset?

odd critique but the calipers are uglier now. look a bit cheap

The DA front mech is the only improvement

They look like MTB rotors rather than Ultegra.

This all makes sense now - presumably not running MTB rotors but running the new DA rotors (although there appears to be zero difference).
https://www.cyclingweekly.com/news/product-news/tour-tech-why-are-pros-running-mtb-discs-and-is-that-a-new-set-of-shimano-wheels-467118

Nice economy of scale for Shimano having to make two fewer types of rotor.

The wheels in that piece will be the new Ultegra ones too I'd assume.

Ahead of the game once again

patonback.gif

The DA front mech is the only (aesthetic) improvement

FTFY

That is what I meant yes, but curious as to what you think the functional improvements are.
Losing a wire from the shifters is pretty much negligible IMO

20% more vertical compliance and 8% increased lateral stiffness, obviously.

It will be a massive improvement to mechanics, and to the customer who pays for our time.

HyperGlide + nothing to sneeze at

hg+

the 9100 series satellite shifters are shit so it is nice they've fixed that (though the 6870/9070 ones were fine)

servowave/increased rotor clearance

160mm cranks available which is cool

like the shape of the new levers. a bit more security than 8070/9170 (like a shrunken r785), but i guess that one is a matter of opinion.

Can ST-RS685-L work with an MTB front mech like FD-M5100-M?

Can I use an 11spd Shimano 105 R7000 Rear Derailleur (https://www.probikekit.co.uk/bicycle-derailleurs/shimano-105-r7000-rear-derailleur/11746883.html) with 10spd shifters and cassette or is there some ratio difference that will mess things up?

If this won't work, what's a similar long-cage RD that will work with 10spd cable shifters?

"Forget about using Dura-Ace 7900 derailleurs with 11-speed levers. The derailleur’s shift-activation ratio is different for Shimano 11-speed rear derailleurs than it is for Shimano 10-speed rear derailleurs. Furthermore, Shimano 10-speed mountain and road rear derailleurs have different actuation ratios from each other, and the same goes for Shimano 11-speed mountain and road rear derailleurs. Prior to road 11-speed and mountain 10-speed, things were simpler; Shimano road rear derailleurs up through 10-speed and mountain-bike rear derailleurs through 9-speed all have the same activation ratio."
https://www.velonews.com/gear/technical-faq-10-11-speed-drivetrain-component-compatibility/

Sounds like a "no".

But maybe a 9spd MTB RD would work with 10spd road shifters?
https://www.youtube.com/watch?v=2Q61siPOo_w

Also, anyone using microshift cassettes?

https://www.microshift.com/models/cs-g100-11-36t/

What are they like?

Which 10 speed shifters? Some of the more recent ones (since 4700 and GRX 10) speed use the 11 speed pull, so will work.

Nah, old DA 7800. According to some youtube stuff (see added video above) they'll work with 9spd MTB deraillers. If that's true it'd allow for some massive cassettes :)

I've built a bike with ten speed road shifters and a 9 speed xtr rear mech. Worked great but also looked great too.

I'm assuming getting hold of old MTB parts is almost as tricky as new Shimano, given most will have ended up stuck in spokes... ?

https://www.decathlon.co.uk/p/9-speed-rear-derailleur-alivio-m3100/_/R-p-X8628967
9-Speed Rear Derailleur Alivio M3100 £35

Would the newer style "shadow cage" 9-spd RDs work?

If the shift-activation ratio is different between 10 and 11 spd, how is this 10 or 11spd RD possible?

https://www.bikester.co.uk/shimano-deore-rd-m4120-rear-derailleur-10-11-speed-M873039.html

Is it only road RD that 10 and 11 spd shift-activation ratio differs? That's not what Zinn said.

just get tanpan/jtek shiftmate

I need to buy a bigger RD anyway, so why would I spend another 30 quid on a Tanpan when I can just get a 9spd RD?

Deore 9spd are still in stock at a few places. If this works with 10spd cassette and 10spd shifters then it's all good.

https://www.merlincycles.com/shimano-deore-m592-shadow-9-speed-rear-derailleur-45049.html

Yes it will work, as long as the 10 speed shifter is not tiagra 4700 and GRX

Got some confirmation off twitter too and this useful guide...

http://blog.artscyclery.com/science-behind-the-magic/science-behind-the-magic-drivetrain-compatibility/

Can I use an 11spd Shimano 105 R7000 Rear Derailleur with 10spd shifters and cassette

No

But maybe a 9spd MTB RD would work with 10spd road shifters?

It will.

Would the newer style "shadow cage" 9-spd RDs work?

Yes.

Is it only road RD that 10 and 11 spd shift-activation ratio differs?

Yes, 10 and 11 speed MTB shifters have the same cable pull per click. That's why 11 speed MTB rear derailleurs are sold as 10/11 speed.