Maximum drop between large/outer and small/inner cog that shifts well consistently (in friction)

[Patrick Moore]

I’m mentally toying with rebuilding my lovely Roadeo with silver and friction parts  instead of the industrial-looking (but seamlessly working) Ultegra 8000 11-sp group.

This group includes a 50/34 double. I think of switching it to a 50 + something smaller than 34. Do any of you have a 20-tooth gap between big and small rings? What front derailleur? How does it work?

I’d center the big ring so that the drivetrain is a 1X + occasional use granny. I’d use the 50 with all 11 cogs, cruising gears would be the middle 5 cogs in the big ring, and I’d use the granny only for very steep hills.

Would this work? Things to be wary of?

Thanks.

BIG RING CENTERED
27.3" wheel
	50	30
14	98
15	91
16	85	51
17	80	48
18	76	46
19	72	43
20	68	41
21	65	39
23	59	36
27	51	30
32	43	26

--

Patrick Moore

Alburquerque, Nuevo Mexico, Etats Unis d'Amerique, Orbis Terrarum

-------------------------------------------------------------------------------------------------------

Executive resumes, LinkedIn profiles, bios, letters, and other writing services

-------------------------------------------------------------------------------------------------------

When thou didst not, savage, know thine own meaning,

But wouldst gabble like a thing most brutish,

I endowed thy purposes with words that made them known.

[Steve]

Patrick, I've run a 50-44-24 triple (non-ramped rings) with a 1990 Deore LX 3x FD without any issues, though it did prefer a crisp upshift. The original small chainring was a 28t, so I may - or may not - have been exceeding Shimano's spec for the FD. 

I don't recall if you're using 'brifters' on your Roadeo, so I should mention that the bike was setup with friction shifting.

Steve in AVL

[Steve]

--- Just adding that I think offsetting the chain line a bit to favor the big ring is a smart approach.