Lowest gearing on a road going singlespeed
 

I am interested in hearing what lower kind of gearing people run , like what is the lowest gearing that people would go to on single speed city bikes or road oriented single speeds. Is 38 x16 crazy low?

the question is a bit vague without specifying wheel/tire size.

I never had problems with 700Cx32mm tires with a 39/17 combo. the top speed is a bit low but I'm not racing anyone. accelerating away from stops is bearable and climbing hills was tolerable. I honestly don't know how people tolerate pushing really big gears unless the appearance and feeling of machoness makes it worth the pain.

currently my gravel bike with 650B x 47mm tires, which splits time between singletrack and paved roads has a 42/18 combo.

Not at all crazy low. I use 38 X 16 on my 26" wheel singlespeed, and a 39 X 17 on my 700c singlespeed 'cross bike. Those combinations yield very similar gear inches, and they work great for the hilly area where I live and ride. I'm a spinner, and really appreciate the faster acceleration of a slightly lower gear. Even that gear would be too big for SSCX racing or a lot of off-road use, but for pavement and smooth trail, it's perfect -- for me at least.

I also ran 39x17 on my SSCX bike. It was pretty perfect for city riding tbh, as I wasn't trying to go for speed and could spin it up pretty decently if I needed to. The only time I wished for a different gear was when hitting trails, where I wanted something lower.

If you are talking about a 27” wheel size like 700cx32, that would be 64 gear inches. That’s not “crazy” low. A little bit lower than I’m running, but fairly nominal for all purpose use. Opinions will vary. It’s the lowest I would consider running for road and easy trail SS.

Otto

I'm running 49 x 20 which is about 68 gear inches. A ratio of 2.45:1

38 x 16 is around 66 gear inches. A ratio of 2.38:1 They're as near as makes no odds identical: about 3% different.

This ratio gets me up most hills in my area, without spinning out dangerously on the descents, and lets me cruise steadily in most conditions. I ride on and off road.

Back in the day when I took it more seriously and rode 7 days a week, I had a theory that the best gear ratio in inches, for a moderately fit rider, is roughly equivalent to the rider's height. I didn't deliberately apply this rule when setting up my bike, but I ended up with a 68 inch gear and I'm 67 inches tall. Coincidence? :)

EDIT I've just measured my wheel with the current tyre on it. Nearer to 27 inches than the 28 I used in my initial calculation, so my gear is nearer to 66 inches.

I should have said , its 27 x 1 1/4 , so very similar to 700c x 32 really. Would you have ever thought about lower than 39/17 or do you reckon that's the cutoff?

totally subjective. I might go lower if the terrain was hillier or the traffic required more stops and starts. the important part is that YOU experiment to find out what works best for YOU.

38x16 on 32 mm tires is 64 gear inches. The old British cycling manuals used to recommend a 65-in gear for gentlemen's single geared bikes, and a 60-in gear for ladies. When Rivendell introduced their Quickbeam sort-of-single-speed c.2004 it came stock with 60 and 48-in gears. The old 63xc.com site used to extol the virtues of gears in that general range for all sorts of rides. I think you're in the ballpark, and 64 gear inches is a very good, useful gear.

https://www.bikecalc.com/gear_inches

yeah, 64 gear inches is where I start for road-ish riding. I think my current gear is 62 GI, which is a little low but I ride this bike off-road quite a bit. my mountain bike is 46 GI as I find that 45-50 GI works well for technical trails.

https://www.bikecalc.com/gear_inches will give you a pretty good idea of what gear-inches are possible on your tire size and gear combination.

Who the hell cares what someone else rides. Do what works best for you. If you want to run a 30-22 go for it. If you want a 60-13 I think you are nuts but have fun. I am good with my 44-17 personally but it ain't about me it is the what is your needed gearing. I probably should lower the gearing on my Single Speed/Fixed Gear RandoCross FunTime Machine at some point and do more riding on gravel with it as it was a bit highly geared last time I rode it longer distance but I still had a good ride.

Learning what gearing other people have found success with can be helpful to those who want to minimize the trial-and-error. If gearing questions are problematic for you, don't click on the thread.

Never said gearing questions are problematic but thanks for playing. You won't go home empty handed you get a free tote bag from Etsy. That's right a Toter Deluxe from Etsy made from the finest cotton canvas with two sturdy handles perfect for all your toting needs.

You selectively quoted what I said and when I said DO WHAT WORKS BEST FOR YOU you cut that part out and went on quoting parts of what I said. The OP wants to run a pretty low gearing and rather than saying you should go up or HTFU or something like that I made it clear don't worry about others and do what is comfortable for you.

44 - 18 with 700x37c tires. Considering going to either a 17 or 16t freewheel, as when riding by myself, I find myself spinning out. 44:18 is perfect for cruising with the little ones though

Well 38 x 16 is about 64 gear inches with 27" tires. That works out to about 15 - 24 kph @50 - 80 rpm cadence. That seems like a reasonable starting point for the average recreational rider. Low enough for short hills and a moderate headwind, and high enough for comfortable flat land cruising. But might be frustrating if you want to take advantage of a tailwind. For that 78 gear inches (26 kph @ 70 rpm) is good on my comfort bike.

As far a lowest goes, The new (2021) Giant Simple One cruiser uses 57 gear inches. I've never ridden a beach cruiser, But I assume ridding in sand (the damp part near the water) needs lower gears then a comfort or hybrid bike.

My apologies for upsetting you. I look forward to reading more of your helpful tips.

I am not upset I was capitalizing everything so it wasn't missed again. Thanks though and maybe I was a touch more snarky than needed. The place I had wanted to order food from is oddly closed today and that upset me a bit but I am a professional I will rise above it.

I used to run 39/16 fixed and 39/18 freewheel on my 27" conversion. IIRC it was 66" & 59". Worked well enough.

For me the 39/18 worked because I could coast down hills. Always rode with at least a front brake.

Like many others have said earlier, it’s whatever is comfortable for you. Who cares what others ride. It also depends on the terrain and types of roads you ride.

That said, the lowest possible gearing a single speed bike can run is a 1:1 ratio, though you might have a hard time finding a cog and chainring that have the same number of teeth.

I run 70.5 GI on my SS daily commuter. I started with 65GI until my legs got stronger to comfortably handle a higher ratio. My winter SS runs at 64GI to accommodate for snow drag. I live in NYC which is 85% flat/flat-ish and has bridges. But hey, you do you.

I don’t fully understand this statement. I agree it would a bit of doing to find actual SS cogs as big as typical chainrings, but there are some pretty small chainring options and I can’t see why there would be any particular reason why the ratio couldn’t be lower than 1:1 just because it’s SS.

OTOH, I would hard pressed to picture a 27” gear being an optimal choice for SS! 😊

Otto

The frame will limit the size chainring and cog you can use. I’d imagine you could go lower than a 1:1 ratio but why would you . . . ?

My bad weather/snow bicycle has 700x32c with 47-18, honestly should go abit lower than that. Next winter will most likely throw a 42 on it.

64 gear-inches seems a bit low for general purpose road riding. Why not something closer to 70-72 gear-inches?

It seems that many off-the-shelf fixed gears come with 46-16 (76 gear-inches) or 48-18 (70 gear-inches).