All about Gearing for Gravel Bikes

fsa sl-k 46 30 crank review
FSA SL-K 46/30 crankset (under review).

Gearing selection is part of the puzzle that goes into preparing one’s bike for a ride, event or race. To some, this subject can be a bit mysterious, almost in the same vein as the right tyre pressure. To have it spot on yields a ride that is sublime and enjoyable. Get it wrong, and those difficult to turn gears can make for a painful experience. A certain level of discomfort and sometimes pain is part of the gravel cycling experience, but I like to keep that to a minimum.

Case in point is some of the gears and chainring ratios I see fit to many bikes sold by prominent manufacturers. In this instance, I refer to the 50 / 34 chainring combination. On a road bike, the venerable “compact” chainring setup as it is known, provides a well-balanced chainring pairing, particularly when it is matched to an appropriate cassette for the terrain you’re riding.

panaracer gravelking sk review
Panaracer Gravelking SK 700c x 38mm.

Things change a bit when you ride on gravel roads. Tyres get bigger, their width and height increases. This changes the outer diameter of the tyre which directly affects your gearing. Suddenly, that 50 / 34 chainring combination on the same 700c wheels becomes a little more difficult to turn over.

To best illustrate this, I have prepared some gearing charts, calculated with the help of an online gearing calculator, courtesy of the late and great, Sheldon Brown. The gearing charts illustrate how much changes when you switch from a 700c x 25mm tyre to a 700c x 38mm tyre. Starting at the top, the first number, 28.5, is the speed in miles per hour possible riding a 50 x 11 gear at 80rpm with a 700c tyre, 172.5mm crankset and an 11-28 cassette. Each gear on the cassette is listed below in order. The next column lists the speeds possible with the 34 tooth chainring, etc. The columns at right are the speeds in kilometres per hour.

50 / 34 Chainrings, 700c x 25mm tyre, 172.5mm crank, 11-28 cassette, 80 rpm.

50 / 34 Chainrings, 700c x 38mm tyre, 172.5mm crank, 11-28 cassette, 80 rpm.

The two charts speak volumes. The 50 x 11 gear combination with a 700c x 25mm road tyre ridden at 80rpm will reach 28.5mph / 45.9km/hr.

Switch to a 700c x 38mm tyre at the same gear and rpm, and speeds change. 29.6mph / 47.6km/hr.

Tyres and gears make a difference, in more ways than one!

More Gearing Goodness

What follows are tables of some popular chainring and cassette combinations in gravel, including some 1x setups. We left 650b wheels out of these tables and a stack of other possible gearing combinations, else this article would go on forever. If you’re interested in calculating your own setup, please visit Sheldon Brown’s gear calculator link.

46 / 34 Chainrings, 700c x 38mm tyre, 172.5mm crank, 11-32 cassette, 80 rpm.
A JOM favorite.

46 / 30 Chainrings, 700c x 38mm tyre, 172.5mm crank, 11-32 cassette, 80 rpm.
A JOM favorite.

1x drivetrains have been making inroads to gravel as our recent video proved. Some riders love the simplicity of only one derailleur, but the following charts illustrate the gaps that begin appearing between the bigger cogs on the cassette. The gearing gaps widen when you increase the chairing and rear cassette size, although they are consistent, particularly on the 10-42 11-speed cassette.

On the positive, companies such as SRAM, leaders in the development of 1x drivetrains, have done their homework. The company’s single chainring drivetrains offer excellent performance and are standard equipment on a growing number of gravel bikes.

40T Chainring, 700c x 38mm tyre, 172.5mm crank, 11-36 cassette, 80 rpm.

42T Chainring, 700c x 38mm tyre, 172.5mm crank, 10-42 cassette, 80 rpm.

1x isn’t for everyone. If you prefer smaller increments between each cog / gear, then a 2x / double chainring configuration may suit you better.

Thanks for reading!

Above, the Moots gravel bike of Jeremiah Gantzer.

44 comments on “All about Gearing for Gravel Bikes

  1. For those of us that have 50-34 (Shimano) and want lower gearing w/o swapping out CR’s, what cassette options work well. I know SRAM offers an 11-36, and that reportedly works OKAY with the long cage Di2 Derailleur, are there other (better) alternatives available?

    1. I run 50-34 SRAM rings with an 11-36 cassette (10 spd) using an X7 mtb rear derailleur w/ Rival shifters. It all works together very well, as long as I don’t try to ride in the 50-36 combo. It’ll go there, but not happily! 😉

  2. I put an 11-36 on a standard SRAM rival derailleur, and though it is beyond spec it works fine. Best not to cross chain, but nothing bad happens. 50-34 up front

  3. I replaced a CX setup (Rival 46/36 x 11-32) with Force 1x (40 x 11-36) and have been very happy with it so far. When I used the double previously, I found that I mostly switched to the small ring pretty quickly once on gravel and stayed there for the ride, except on some paved transition roads. I really like the simplicity of the single and don’t miss the latter gears I had before. I dropped chains a few times with the double, but never with the single. I’ve also added the K-Edge Cross Single XL chain catcher for added security.

  4. Many thanks for a great article and perfect timing ’cause I’m just looking at changing my gearing! “46 / 30 Chainrings… A JOM favorite.” — mind sharing what crankset you’re using?

    1. I know plenty of riders who use 48 / 34, but 48 / 36 won’t be a problem. You won’t have the slighter lower small chainring for climbing is all.

    1. That will work no worries provided you use the XT or XTR Di2 rear derailleurs. Regardless, if you use the Ultegra Di2 mechanical brake shifters or the hydro ones, it will work. You’ll have to place the eTube software into MTB mode during configuration.

  5. I’ve been really happy with my setup since changing over on my GR250.

    Front chainrings 46/30 on FSA Omega Compact cranks. (std was 50/34)

    Rear SRAM 11-36 (std was 11-32)

    This is running with Shimano 105 11 speed medium cage derailleur. (did not need a hanger extension)

    1. Old thread I know but where did you find a 30t that would work on the Omega crank? It’s 4 hole 110 BCD right?

  6. Not being the techy gear guy I have a few questions. First My 2016 Raleigh Tamland was to come with 46/34 gearing but instead came with 50/34. Rear was Shimano 11 x 32. I changed out the 11 x 32 with Sram 11 x 36 and a road link. What I have noticed in the smallest 2 gears when you stop pedaling I don’t know if you would call it slippage or chaining. For sure it is a weird feeling which I have never had on a bike before. On another note my bike had the FSA crank set on it and some kind of cheapo rings. I hit something or at least my LBS said I hit something on the Crush and Run II out of Litiz Pa. a couple of weeks ago and bent the outside front big chain ring. I replaced it with a Shimano 50/34 105. I see you have listed that you love the 46/34 which was suppose to come on my bike. Don’t you lose some speed on the flats in the high gear range with 4 smaller gears than the 50? Just asking as I still am trying to get my bike dialed in. I will say the Kenda Flintridge Pro 40 mm that I put on my bike are bullet proof but boy are they much slower running than the Clement MSO 40 mm which came stock on my bike but were non tubeless. Any help/comments is greatly appreciated.

  7. Just wanted to add that for MTBers like myself, who are perfectly comfortable riding a very, very wide cadence range (insensitive to large gaps), 1X on the road is not range-limited. Using Wolf Tooth RoadLinks, I am successfully running 1×11 44T x 11-50 on my Sunday/race/club ride/sportive bike with a mix of SRAM Force1 & Rival1 (Long Cage), and 1×10 42T x 11-46 on my enduroad adventure gravel commute touring packing all-road grinder with SRAM Force and a GX 2×10 Long Cage derailleur. Didn’t even have to max out the B-screw on either setup, and they shift smooth, quietly and without hesitation all the way up and down the cassette, although it will drop one or two cogs down the cassette if I backpedal in the largest cog (but I almost never backpedal on road or gravel). I’d love to attach pics, but don’t know how/can’t on this discussion platform.

    -Ed

  8. Just sharing – Love my SRAM Force 1 with 40 chainring and the (ridic expensive) 10-42 outback. It’s quiet, fast-shifting, simple and I don’t miss the more nuanced gear when riding gravel. The 40:42 is great for climbing tough gravel hills and the 40:10 lets me ride at ~25 MPH on hard-pack flats or downhill, which is fast enough for me.

  9. I just switched the default 11-32 on my Litespeed Gravel (50/34 Shimano) to a 11-40 with an Deore XT long cage and a Tanpan from Wolftooth (road shifters to MTB derailleur conversion). It makes a great difference at the end of a long ride. The clutch in the XT derailleur is a welcome addition in the rough stuff and the new range of gearing was exactly what I was looking for (5.5mph – 29.6mph @ 80rpm). The change only cost me ~$200 USD. Installation of the Tanpan and the new derailleur was easier than I’d expected.

    https://bike.shimano.com/content/sac-bike/en/home/mtb1/drivetrain/cassettes/cs-m8000.html

    https://bike.shimano.com/content/sac-bike/en/home/mtb1/shifting—braking/rear-derailleur/rd-m8000-gs.html (I got the sgs-long cage, but they don’t have a nice link to that here.)

    https://www.wolftoothcomponents.com/products/tanpan

  10. Tanpan +1!

    I ride an 11-speed set up using Ultegra 46/36 crankset with an 11-40T cassette and an XT GS rear mech, matched up to Ultegra shifters. All made possible by using the Wolftooth Tanpan. Using 700 x 38c tires. One of my favorite investments on my bike!

    Wolftooth also do the Road Link which basically allows you to use a 40T cassette with your normal road mech, a cheaper alternative, but I’ve not tried it yet.

  11. Thanks for an interesting article!
    I have Force1 derailleur and shifter, 10-42 cassette, Easton cranks, WTB Horizons.
    38t ring for long days in mountains, about 10k feet elevation total or more.
    42t for short rides or hard pack flats.
    48t is perfect for city road rush and to biting e-bikers 🙂

  12. trying to figure out what’s the biggest cassette size I can put on my bike.
    I have a 6700 ultegra group set – 10sp (52-39-30) and 12-30.
    I moved to a really lovely place with super steep gravel…and am finding the need to make the cassette bigger, if possible. But I’m a bit confused with what might be the biggest the cassette I could put on. I calculate my chain capacity at 22+18 = 40T . I currently have a GS ultegra rear mech, but I also have a SGS deore XT shadow rear mech I can put on it.
    I do a lot of loaded ON to multiday touring and I’m struggling to get up some of these hills just with some water on board on morning rides. I also, can’t afford to buy a new bike. Thanks.

  13. Great article! I am exploring options now (on two bikes – one with Tiagra the other running 10-spd SRAM). As of now both have 155mm 50-34 chainrings (Cobb) after a recent bike fitting as I am working around hip mobility issues. The Tiagara (’18 Vaya) is set up 11-34 in the back. I like it! The SRAM on my Crux is set with 11-28 in the back and I’m switching to an 11-32.

    My questions is how do you think the short-cranks impact my choices? I have looked at Sheldon Brown’s site and am still working thru it all. The wheel/tire size is close enough for now as I run 40c tires on both bikes.

    Thanks for a great article.

  14. What’s my best option for buying/ cobbling together a 48-34 11-speed crankset?

    Reason being that I’ve put an 11-36 cassette with a 50-34 compact and although clearing the 36 sprocket is no problem, I’m over the derailleur capacity, such that the chain is slack in the small-small cross chaining situation.

      1. I just got the White Industries G30 crankset (in silver) with their TSR (narrow-wide) chainring & BSA BB for my single-speed and it is indeed a thing of beauty! Not cheap, but about as perfect as they come.

        1. Be sure to perv on the crankset a while before you install… and perv again once it has been installed. White Industries components are so so nice.

          1. Ha. I didn’t get a chance to see it until the bike was built up. My shop did a complete rebuild of my 2016 All-City Nature Boy as per my spec. Includes silver White Ind headset, silver Thomson seat post and stem, silver Ritchey classic handlebar, and wheels built up from silver White Ind ENO hubs and polished silver Velocity Quill rims. The bike is quite the attention grabber now.

    1. Dude who cares if it’s slack in small-small. You should not be in that gear, really you shouldn’t even be in small-2nd or 3rd small. If you find yourself getting down there, that means you’re no longer climbing a big hill and should be back on the big ring. There is a cog somewhere in the middle of the cassette that matches the gear ratio of small-small on the big ring and is a much more efficient, not cross chained option. Also then you’ll be ready to shift either way to an easier or harder gear. On the little ring and one of the small cogs, if you want to shift to a harder gear, you only gain 1 tooth, which with a 34t chainring doesn’t get you much. I.e. 34×12 is not much harder than 34×13. Get back on the 50t ring before you start shifting down into the small cogs.

  15. Will chip in my two cents/sense worth. I’m riding a Bombtrack Beyond for both Gravel and Road (road training for gravel) and have the following setup: XT 11-36 rear and SRAM (X5…always feel like I want to upgrade by it’s bomber) front 2X 40/28. Running 38mm Compass Bon Jons (OMG!!! Love) and I start to slightly spin out at about 45-46 kmph. OK for me unless I get absorbed into some big ring roadie pack….in which case I’m probably looking for a way out the back. Running 105 shifters w the XT and using a jtec thingamawhatever to get the cable pull right. Works flawlessly!

  16. I would like to upgrade my Specialized Diverge A1/2015. I am running 34/50 up front and 11-28 Sram cassette with a Rival short cage with Rival 10 speed shifters at present. I have just purchased a Sram Rival 10 speed Wifli medium cage (New) and a Sram 1071 chain. I would like to upgrade to a Sram 11-36 MTB cassette but not sure if this will be advisable or work.. ? (I would probably need a Wolf Tooth extender as well ?) I would really appreciate any Technical analysis and advice for the best way forward. I can not find any blog or literature relating to this set up. This is causing me some anxiety and stress as I would like to get it right.

    Kind regards..

    1. Hassan,

      According to SRAM, the Rival wifli mid cage rear derailleur can only handle up to a 32t cog. Whether the wolftooth extender will help you or not? I can’t say.

      My solution was simpler. I bought an X7 10 speed mountain rear derailleur (https://www.sram.com/sram/mountain/products/x7-rear-derailleur) to use with my Rival 10 speed shifters and 50/34 chainrings. The derailleur and shifters work perfectly together and – a nice fringe benefit – I don’t have to shorten chains to fit. SRAM 10 speed chains end up being the perfect length right out of the box.

      If I had it to do over again today? I’d probably invest the money in a subcompact crankset and run smaller rings & a smaller/lighter/tighter cassette w/ the rival RD I had, but those options didn’t really exist at the time, and the clutch on the X7 keeps things nice and quiet – so that’s nice.

  17. I forgot to (explicitly) mention, that I’m running the same cassette that you want to use. A PG1070 11-36. In case it wasn’t clear already. 🙂

  18. I am looking at a gravel bike with a 46/34 crank and a 11/32 cassette. Thoughts? Not riding too many super steep climbs.

  19. hii
    orbea terra SRAM 1×11. front chainring 40t , cassette 11-36
    usually 30% light gravel 70% road
    a few climbs on the way approximately 1 kilometre length, i manage to pass them on gear number 4/5 (the small rings) standing up
    on the flats, it’s usually the lowest gears 1/2 ( the small rings) no more gears left to go down.
    want to change the chainrig to 44t or 46t
    not sure which one to choose?
    thanks for the help!

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