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Hi, looking for help on a potential bodge 🙂
I have a Tiagra 4700 short cage rear derailleur - currently running an 11-28 cassette. I'm looking to go for a more spinny gear but i'm not sure if either of these cassettes will work ok? or if I would need a new rear mech.
- Shimano Tiagra 11-32 HG500
- Shimano Ultegra 12-30 6700
The bike it's going on is a Trek Emonda ALR 2016 with a compact 50/34 chainset
Cheers
Andy
Both would be fine 👍I think you can go to 34 with that mech.
It won't work with your current short cage mech - you'd need the longer mech.
See specs for details.
Short
https://bike.shimano.com/en-EU/product/component/tiagra-4700/RD-4700-SS.html
Long
https://bike.shimano.com/en-EU/product/component/tiagra-4700/RD-4700-GS.html
It won’t work with your current short cage mech – you’d need the longer mech.
Shimano do say that, but real world experiences say different. Have a google OP, certainly a 32t should be fine with a B screw adjustment.
Ok thanks, I'll have a google. Thinking the ultegra might be a good option as a slight upgrade in terms of weight too.
Thanks
I run a 105 short cage mech on the gravel bike and a 32T is maxed out with the b screw right in , Cant see it working on a 34T
Meandyuk - i have a brand new 4700 medium cage derailleur you can have for £15 posted if that helps, it runs 34t no probs. I had a short cage and trying to get it to work with a 32t was very problematic and frankly not worth the hassle.
Thanks, i'll keep it in mind.Currently thinking I'll go for the 30t so hoping this will be less troublesome than a 32t with the short cage rm
I think a 30t will be ok with the short cage, probably the cheapest option too.
short cage will 'probably' work on the 32Tbut it depends on your hanger and how much b screw you have to play with.
plus depending on the front rings you use it could be pretty damn tight if not locked in big/big. I've seen a short cage mech work with an 11-32 cassette with 34t chainring but not be able to cope with big/big on a 46T outer.
TBH I would just buy a mid cage mech
I’m looking to go for a more spinny gear
The 30 tooth cassette will only give you "half a gear" more - will that qualify as 'more spinny'?
The 11-32 Tiagra cassette will give "one gear" more, but has an annoying (to me*) gap at road speeds as it doesn't have a 13T sprocket (it goes 11 - 12 - 14).
*I replaced the 11T & 12T with new 12T & 13T sprockets to give me 12-13-14 and don't miss the 11T ever (50/34 chainrings).
If you go with ultegra you will need the 11 speed version. Tiagra 4700 series is the same pull ratio as the other 11 speed shimano stuff even though it's 10 speed.
If you go with ultegra you will need the 11 speed version. Tiagra 4700 series is the same pull ratio as the other 11 speed shimano stuff even though it’s 10 speed.
The OP is swapping cassettes, not mechs.
Pretty sure 4700 has different spacing than all the other groups, and all other tiagra.
Now i'm a little confused - will the Ultegra 10speed 12-30 cassette not work with a 4700 rear mech then?
I know its not a long more 'spinny' but I think it may make a bit of a difference here in Yorkshire... plus I need a cassette for the turbo so may as well chuck the older cassette on that and use the better one for going outside with.
Cheers.
Now i’m a little confused – will the Ultegra 10speed 12-30 cassette not work with a 4700 rear mech then?
It should be fine - I'm pretty sure that the cog spacing on new Tiagra 10 speed is the same as older Ultegra/ 105 10 speed.
Thanks!
Ive got tiagra without looking it up there are some shifting diffences with other 10 speeds so be ware y about mixing with 6700 without more information.as others have already said.
will the Ultegra 10speed 12-30 cassette not work with a 4700 rear mech then?
+1 should be fine - the pull ratio of the rear mech is same as 11 speed, but cassettes are normal 10 speed.