Question re: subcompact gearing

[ERK55]

OK, if so I were to consider a subcompact double setup with the intention of achieving a ~ 1:1 ratio at the lower end..... (Campy if that matters)

Better 48/32 chainrings with a 32T cassette
or
46/30 with a 29T cassette ?
Thanks

[fa63]

I tried 46-30 chainrings briefly, and found the compromise on the top end to be too much for my liking for road riding. I now use 48-32 Praxis crankset with a 11-32 cassette on a Campy Centaur drivetrain and couldn't be happier.

[palincss]

OK, if so I were to consider a subcompact double setup with the intention of achieving a ~ 1:1 ratio at the lower end..... (Campy if that matters)

Better 48/32 chainrings with a 32T cassette
or
46/30 with a 29T cassette ?
Thanks

In terms of efficiency you're going to be better off with bigger chain rings and sprockets. However, the difference between the two you're comparing is hardly likely to be of any significance. The specific gearing combinations, though, may be. fa63 had a problem with the high end gearing range available with a 46T chain ring. Others might have the opposite problem: for me, 46x11 is unusably high, although with the right wheel 46x12 is just right.

The best thing in my opinion would be for you to plot out the gearing charts for all (assuming there are more than one of each -- I don't know Campagnolo, so am not familiar with what's actually available) the cassettes that have a 29T and a 32T bottom with the chain ring combinations you're considering. Look at the overall range, both at the high and the low end; look at the spacing between the gears; and look at the crossover points. Do they make sense for you, knowing the gears you use now in the terrain in which you ride? It's possible one of the combinations is going to stand out as better in some or even all respects for your specific situation.

[Cornfed]

If you decide on the 48/32, I've got one available ...

https://forums.thepaceline.net/showthread.php?p=2464485#post2464485

[livingminimal]

I tried 46-30 chainrings briefly, and found the compromise on the top end to be too much for my liking for road riding. I now use 48-32 Praxis crankset with a 11-32 cassette on a Campy Centaur drivetrain and couldn't be happier.

I have to hit about 31mph to spin out my 46-11. Bravo to you.

[hobbanero]

I use the Praxis 48/32 rings. With a 37mm WTB Riddler on the back, the 48x11 is more top end than is usable. Would rather have 46/30 and get an easier low gear. If you are using smaller tires, then the gearing will be smaller and the larger rings may be perfect.

[Clean39T]

I use the Praxis 48/32 rings. With a 37mm WTB Riddler on the back, the 48x11 is more top end than is usable. Would rather have 46/30 and get an easier low gear. If you are using smaller tires, then the gearing will be smaller and the larger rings may be perfect.

This is a very good point, but still splitting hairs..

700x37c at 110rpm: 46x11 = 37.5mph, 48x11 = 39mph
700x25c at 110rpm: 46x11 = 36mph, 48x11 = 37.75mph

My 44x12 I'm going with on my Kirk at some point will still only have me spinning out at 36mph - I'm okay with that.

That gearing will also allow me to stay in my big ring down to about 9-10mph in the 23T (3rd from the top). And will get me down to 5mph at 65 rpm for the 20% grades in my 28x29 - or mountain goat range in a 28x32 for some very special occassion.

[stev0]

FWIW, I run 42/28 on my Lemond Poprad Disc, which gets used 80% road 20% gravel, and never feel like I need more low gears. I don't think I ever get near 30mph on flats, and don't really feel the need to push on descents, so it's allllllllll gravy. :banana:

[R3awak3n]

I really liked my 48-32 but also have had 46-30, also great but would prefer the 48-32 unless I am doing insane climbing (and even then would probably just go up to a 32 cassette for 1 to 1 ratio).

I really like 48... now back on a 50 for that bike and prefer the 48, can stay longer on the big ring and will never max that gear out.