Shimano chainring combo

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The usual combinations for front doubles are 53/39, 52/36 and 50/34. Shimano tech docs “recommend” that you don’t mix these about as you might ruin the shifting.
I’m wondering whether anyone successfully uses 52/34 though? It’s an Ultegra 6800 setup. I can’t find any specification for whether the front derailleur will cope with an 18T difference or not.
Not that fussed about the different jumps in overall gearing, but more to get the lower range option with the 34.
Anyone?
I’m wondering whether anyone successfully uses 52/34 though? It’s an Ultegra 6800 setup. I can’t find any specification for whether the front derailleur will cope with an 18T difference or not.
Not that fussed about the different jumps in overall gearing, but more to get the lower range option with the 34.
Anyone?
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The rest of the internet is quite a good resource of success stories, but mainly with Di2, unsure if it's ok with mechanical.
I personally changed a 53/39 to run as a 53/36, and despite what people pipe up to say about extra wear/stress on the system, it feels like it's a factory spec change, it's seamless, and so slick and smooth, a real joy to ride, and has made the bike so much more usable than it would have been for me otherwise - and all for the princely cost of £36!
Mine is mechanical 9100, and is in theory 1 tooth outside of the recommended max.
Yours would be 2 teeth out - I'd be surprised if it caused you any issues, I'd be inclined to simply go gently with the pedalling as you change on the front, but then I suspect most of us who are not racing do anyway.
Please do update should you go for it, would be intrigued to hear how it goes, as a 52/34 also appeals to me on another bike :-)
Marin Palisades Trail 91 and 06
Scott CR1 SL 12
Cannondale Synapse Adventure 15 & 16 Di2
Scott Foil 18
If it’s no good I’ll probably switch to the 50/34 rather than 52/36 - need more help up hills than down for sure!
Marin Palisades Trail 91 and 06
Scott CR1 SL 12
Cannondale Synapse Adventure 15 & 16 Di2
Scott Foil 18
No problems with gear changes, and rarely drop a chain. Chain would be a bit slack on the 34 when down towards the bottom of the cassette, but I never go down there anyway.
Use 53/36 on another bike with similar results.
I don't get much use of 50-12 and even less from the
-11 but I'm feeble and don't have many long sweeping descents.
I believe the 50 and 34 rings have an A tooth profile whereas the 52 and 36 have a B profile on some teeth to aid shifting.
An update - I’ve done this change to use 52/34, and front shifting seems almost identical - perhaps a smidge more noise and two nanoseconds slower to ramp up, but no issues. The downshift from big to small is noisier too, a bigger drop I guess.
Only practical issue as expected is chain length and tension. Using an 11-28 cassette, on the small front ring the chain tension is a little slack in the 3 smallest cassette sprockets, so I just shift gears a bit more often to avoid that. Rarely used those ratios anyway.
Otherwise seems fine. I’ve not fitted a chain catcher yet on the front mech, will do when I can find one in the lbs… but so far no dropped chains. (Not big miles yet though by any means)
I had a 52/36 and needed to replace the 36. A 50/34 would be a better suit for my cycling... erm...I hesitate to use the word abilities. I toyed with the idea of just replacing the 36 with a 34 but with the chat about big drops and the difference between A and B tooth profiles, I changed both. Good to know that the 52 ring is not a scrapper and may come in useful in the future.
I certainly had no need of a 52 x 11 combo.
However, I run a 11-32 rear, would 52/34 be pushing my luck??
It's just a hill. Get over it.
https://www.mantel.com/uk/shimano-105-5800-chainring
Dunno whether a medium/long cage derailleur would solve that to some extent though, if you can get the shifting to work. Not tried that on a roadie.
I might have to be less tight and just buy a 50 outer as well! Or I could swap in the cranks from another bike (wrong chainring type, tho', old 5 arm model)
It's just a hill. Get over it.