Going from a double to a single chain ring.

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Juanmoretime
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by Juanmoretime

I have a double 50,34 on my gravel bike. What size chainring should I consider if I go to a single ring? My cassette in a 11-26 10 speed. I almost rarely use the small ring.

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wheelsONfire
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by wheelsONfire

Juanmoretime wrote:
Fri Dec 16, 2022 6:26 pm
I have a double 50,34 on my gravel bike. What size chainring should I consider if I go to a single ring? My cassette in a 11-26 10 speed. I almost rarely use the small ring.
I would take a serious look at Rotors suggestion!

https://rotorbike.com/1x13-groupset-road/
Bikes:

Ax Lightness Vial EVO Race (2019.01.03)
Open *UP* (2016.04.14)
Paduano Racing Fidia (kind of shelved)


Ex bike; Vial EVO D, Vial EVO Ultra, Scott Foil, Paduano ti bike.

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markdjr
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by markdjr

46t, maybe try to get a wider range cassette if you find you need an easier gear.

hwyix
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by hwyix

40T front and 11T is good enough for 99% of the people.

40 x 11T at 100 rpm is good for 28 mph


https://www.bikecalc.com/speed_at_cadence

How many people "pedal" at speeds for 28 mph and for how long really?

Whats speeds do you pedal at ( not coast down 15% + grade ) ? What's your slowest you climb up hil where you live and what's your top speed you can mantain for 30+minutes? With that data you dial in what compromises you need with your gearing.

jadedaid
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by jadedaid

So I had tried to run a bike with a 40t chainrng and 11-28 cassette, and found that spread of gears to be really lacking. I thought I got the worst of both worlds with this 1x setup. If you're sticking with the 10 speed, are you limited in casette size?

If you're already saying you rarely use the small ring, probably upper in the 40s is what you're looking for? As hwiyx said you need to determine what gear range you're going to use. I know the current trend is to argue against bigger chainrings, but I found myself spinning out 40x11 often enough that it annoyed me. I want my largest gear ratio to be 4+. All my rides involve significant tarmac sections and you need that gear, but not everyone does!

robertbb
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by robertbb

I agree with what has been said above; a 40t or 42t up front with an 11 (or 10) small cog is all most people really need - especially when running modern large-ish tyres of 32mm+

If you're talking Shimano, this pairs up very nicely with an 11-40 MTB cassette using a GRX rear derailleur. The 11-42 is also a good option if you can tolerate slightly larger jumps between some gears towards the larger cogs.

blaugrana
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by blaugrana

In my experience with a 40x11-40 setup, I very rarely spin out, I don't see the need for a longer gear at all. It depends a lot on the type of gravel you do, of course. I try to avoid paved sections on my gravel rides, and I also prefer more technical gravel, so on the rare ocasion there is a paved downhill where I could pedal faster, I just use it to rest a bit.

For gravel races on fast courses this might be different, though, also depending on how strong you are. So in that case a larger chainring might make sense, if there aren't any hard climbs where you need the easy gears.

hwyix
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by hwyix

How are you guys pedaling at 28 mph unless sprinting for minutes/seconds? If you are racing sure but if you are racer you should know what kind of gearing you need and would not be asking simple question on the forums so I assumed the OP is not racing.

The few long straight down grades that I could spin out a 40T x 11T combo I would not have wanted a bigger front chainring because I would have been suffering more on the climb. I would rather have the proper gear going uphill and coast at 30+ mph on the down hill.

ooo
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by ooo

it doesn't make sense to start 1x conversion with RD upgrade and/or STI upgrade. First change consumable parts:

1. try 34x11-26, even thou you "almost rarely use the small ring"

2. try 38x11-26, with cheap 38T chainring that is compatible with your current crankset

next steps:
- change front ring by 4T or
- change cassette by 4T or
- change front ring by 2T and cassette by 2T

(for more suggestions, you can post preferred cadence number and screenshot samples of Strava activities)

if you have rim brake bike with ST-7900/7800/6700/6600/5700/5600/4600 shifters - best low profile 1x specific RD with huge clearance that is compatible with 10 speed road+mtb cassettes is Saint RD-M810-SS (11-23T to 11-36T), but it is not necessary to change RD.

if you ended up on 36T+ cassette, you may want to upgrade to 12 speed.
'

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Juanmoretime
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by Juanmoretime

I wound up going from a 50, 34 front chainring to a 46 tooth narrow/wide oval chainring and to a 11-32 Red cassette,

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