Tiagra 4700

[neilob]

In a recent post I can no longer find, someone was stating that the new 4700 Tiagra was not compatible with other 10 speed systems. Do I remember right? But in terms of compatibility, I would like to know if I can use the 4700 rear mech with 9-speed XT shifters or if it won’t work. Obviously I will change the cassette but will a 10-speed chain be ok on a 9-speed cassette?

[meic]

Apparently the 10 speed 4700 shifters are set up so they work with the same rear derailleur ratio as the 11 speed groups released at the same time.

So a 4700 rear derailleur is compatible with an 11 speed 5800/6800/9000/9100 shifter or derailleur.

I think that this makes the pull of a 4700 STI unique other than through luck.
The 4700 rear derailleur isnt designed to work with 9 speed or any other 10 speed, just the 11speed systems listed above.

All of this is just what I have "picked up" and needs verification.

[rjb]

this could be the post you were looking for.
viewtopic.php?f=5&t=122301&hilit=4700

[Brucey]

In a recent post I can no longer find, someone was stating that the new 4700 Tiagra was not compatible with other 10 speed systems. Do I remember right? But in terms of compatibility, I would like to know if I can use the 4700 rear mech with 9-speed XT shifters or if it won’t work. Obviously I will change the cassette but will a 10-speed chain be ok on a 9-speed cassette?

RD-4700 will not work with a 9s shifter and cassette. You need a shimano 8s, 9s, or (any) other 10s road mech.

10s chain will work but not perfectly on most 9s sprockets/chainrings. Best to use 9s chain with 9s sprockets.

cheers

[thelawnet]

In a recent post I can no longer find, someone was stating that the new 4700 Tiagra was not compatible with other 10 speed systems. Do I remember right? But in terms of compatibility, I would like to know if I can use the 4700 rear mech with 9-speed XT shifters or if it won’t work. Obviously I will change the cassette but will a 10-speed chain be ok on a 9-speed cassette?

8-speed road/mtb = 4.80mm cog pitch, r/d shift ratio 1.7 =2.82mm
9-speed road/mtb = 4.35mm cog pitch, r/d shift ratio 1.7 = 2.56mm
10-speed road = 3.95mm cog pitch, r/d shift ratio 1.7 = 2.32mm
10-speed mtb = 3.95mm cog pitch, r/d shift ratio 1.2 = 3.29mm
11-speed road = 3.74mm cog pitch, r/d shift ratio 1.4 = 2.67mm
11-speed mtb = 3.90mm cog pitch, r/d shift ratio 1.1 = 3.55mm

4700 shifter/mech uses 10-speed cassettes, but with a 4700-specific 1.4 shift ratio = 2.82mm

This means the 4700 rear mech would work with 8-speed shifters, but not 9-speed.

[Brucey]

shift ratio isn't exactly 1.7 BTW... (and nor is it 1.1 and 1.2 for MTB 11s and 10s systems either).

If you use 8s shifters on a 9s cassette with RD-4700 you might get good shifting but only over eight sprockets...

cheers

[neilob]

Thanks everyone for your usual excellent advice and knowledge. I am converting my wife's drop bar 4700 equipped bike to straight bar.....easiest solution seems to be to buy the Tiagra flat bar 4700 shifters which I have just done.