# On a mountain/gravel bike, how slow can you go while pedaling before falling over?

Sorry if this is a weird question

I’m trying to figure out what gearing I need on my Cutthroat that I’ll be using for hilly gravel rides. I’m looking at the gear calculator and wondering at what speed one would basically not be able to continue going forward without falling over!

For example, 36x42 with 2.2" tires puts you at 4.4 mph at 60 RPM, but 30x50 at 60 RPM puts you at 3.1 mph. Are you even upright at that point? That’s easily walking speed. I know much of one’s gearing choices depends on fitness but I don’t know if I’m going nuts worrying one ratio gets me 4.1 vs 3.8 mph when I’d basically be falling off anyway

I guess I’m trying to figure out if I need to go down the Eagle mullet rabbit hole, or work with more gravel oriented gearing and play with chainrings as needed and as I get stronger.

This is along the lines of questions like “How long is a piece of string?”.

Your lowest controlled speed will vary with each rider. Considering I rode observed trials for two decades (the purest sense of balance skill I can imagine on a bike), I can ride in full control at speeds in the 0.# range.

You can generally test this by grabbing your bike, make sure you have a speedo visible, drag the brakes or better yet, find a decent hill to practice… and then just ride as slow as you can. People tend to “snake” back and forth as they hit their lower limits of control. Your current setup may lead to a super low and unrealistic cadence, but you should be able to get a sense of your lower controlled speeds from a test like this.

As with any part or riding, balance is essentially sensing your current condition, predicting future changes, and acting to correct any imbalance to keep at the desired goal (upright and straight unless turning intentionally).

I know pedaling my Eagle MTB’s can feel super odd in the low gear on the flats, but on a proper hill, I can claw up stuff that might be faster to walk. Just depends on what you want to do.

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This is super helpful Chad…and I certainly appreciate the vague nature of the question. I guess I never really tried to go that slow on a proper ride so I didn’t know what to expect.

On flat ground. I’ve maybe gotten down to 2 mph or something, weaving around to stay upright as my son was learning to ride. I should have known there was alot more to it!

Maybe the question could be reframed something like…how slow does one typically like to ride before hopping off and walking? Figured more experienced people (like you ) might have more insight.

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I am a stubborn person, and always up for a technical challenge on the bike. Based on that, I rarely walk unless I am absolutely forced to from super hard terrain (extra steep / rocky or any combo) or I am trying to preserve energy for a particular reason (hard section within a much longer ride).

Considering that most MTBs these days are running a 28t to 32t up front, with 50t to 52t in the rear, you can get some low speeds at low cadence. For me, if the force required to hold that low gear is exceptionally high and planned to be long-ish (more than 30 seconds?), I might get off. I know many people will step off well before my limit, so the 3-4 mph range as a low makes decent sense to me.

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Doesn’t really answer your question, but in my (admittedly, limited) experience with riding very hilly gravel, I tend to lose traction (rear wheel) before I go so slow I’m having a hard time moving forward.

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I wouldn’t be worried about falling over at that speed. Presuming you can push enough Watts to maintain that cadence, if you’re still pedaling, you’ll still be upright.

As Chad ways, how long is a piece of string, but I’d work out how slow you can maintain your cadence and then see if that’s a reasonable cadence for the gearing and gradient you have in mind.

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Main question is how steep you expect to be riding.

Here’s a segment I rode this evening on my gravel bike - 4.5mph on a 12% gravel grade. This was on pretty good quality gravel.

I was riding slowly, but far from falling over. And definitely would not have been tempted to get off and walk.

At other times, I’ve ridden climbs on my gravel bike that would be better suited to a mountain bike, with big embedded rocks, requiring thoughtful line choice. Probably riding about 3 mph. At that speed and terrain, I’m approaching the point where it’s 50/50 on if I’d save energy by walking.

FWIW, my lowest gearing is 31-34.

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Many years ago, I did the Mt. Evans race…brutal conditions on the final section up from Summit Lake. Cold, snow and really windy.

I came around a switchback, hit a head wind, was giving it all I had (in a 39x27 ), looked down at my Avocet computer and saw 2 mph.

The next switchback coming back into the headwind and the wind knocked me off my bike.

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That is a difficult question. I think one limiting factor is the gradient: I have ridden up an incline at lake Garda on my mountain bike where I would have to drape myself over the handle bars so that I wouldn’t fall lose traction on the front and tip backwards. Otherwise it just depends on your gearing and your bike handling skills.

How fast can you walk up the hill in question, while pushing a 25 pound gravel bike (Cutthroat with pedals and trimmings)? Probably less than 3mph. I find I pedal till I can’t, which is beyond threshold, and then start pushing, and it is so much harder (and slower) than just walking. If the pitch is long enough to warrant walking I think most MTB riders hop off between 2.5 and 3.5 mph. With a gravel bike, the option of a double chain ring sounds amazing to me, maybe even with a 10-50 cassette. I wish I had that gear diversity/range on my modern MTB.

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I’m a horrible climber and my Garmin often tells me I am going 2-2.5 mph
28x42 gearing with cadence in the 40’s.
Not sure I could go so slow consistently on a flat area, but the resistance of climbing keeps it going.

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It all depends on how long you can trackstand for…

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As far as slow speed, that’s a matter of control. @Andygajda’s comment about a track stand isn’t too far off: how well can you maintain control at slow to no speed? Also, when your handle bar goes right because of an unbalanced pull or a rock or root, are you putting your foot down or pulling up the wheel or otherwise adjusting?

Specifically onto gearing, if you’re doing hilly terrain, and I think you previously said you intended to, then I would consider the mullet setup. I went that way earlier this year and went from a 10-42 to an Eagle 10-52. The “top end” remains the same but on the “low end,” options open up. (Now, my LBS accidentally went with a 40t chainring in the upgrade instead of replacing my existing 42t because the 40t is “normal.” Going from 40 from 42 helped with the low end, obviously, but I lost the “top end,” so now I have a 42t when the top end is needed.)

There’s a fun climb near me I hit occasionally (at least enough to be the local legend) that’s a hair more than a quarter-mile with an average of over 21% on actual gravel. In parts, the gravel is shoved aside or downhill to expose hard dirt can exposed and in others the big pebbles are deep, not to mention the potentially wet leaves in autumn, the snow, or slick metal (run off ditches so water doesn’t flow down the trail; formed by two old rails creating a gutter about 3" wide). It’s “easy” to go 2mph up that with the mullet setup because of the cadence and it was much harder to do that with the 42x42 and the resulting lower cadence. So, it really depends on your needs.

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Chiming in to say I agree that I tend to lose traction before I lose the ability to stay upright due to speed.

I also want to contradict Chad. Please, for the love of all that is good in the world, do NOT do this experiment with your Speedo visible.

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As usual, there’s waaaaay more to consider than I originally thought when asking the question

Thanks all…lots of good stuff to consider!!

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How slow, pretty damn slow! I grabbed a couple portions from a MTB 100 earlier this year. I’m sure I was in my 32x52 and looking for an easier gear, lol.

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Without checking some of my times and speed on Strava I suspect that there’s quite a few where I’m going at 5km/h for a while.

That got me thinking: I wonder which Strava segment has the slowest speed for the KOM? There’s one past our house (grass lower half, tarmac upper) with 9.4km/h for the KOM.

Edit: Just found this one https://www.strava.com/segments/1248816 - 6.1km/h. I’m just off the leader board on that one

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Pinnacle mountain North Carolina, This climb has a grade from 10% to 20%. I was pushing very hard in some spots and as you can see my average speed was 5.4 miles an hour. If you are peddling, you’re still moving and I don’t think you would fall over unless you’re going 2 miles an hour maybe idk

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Since I don’t see it’s been mentioned, and possibly less relevant for gravel, but being able to keep a cadence helps me with weight distribution on steep technical climbs on the MTB - I find if I’m dropping down to very low cadences and forcing it, I’ll need to be putting out a lot of torque with each pedal stroke which means shifting around on the bike.

So rather than it being “how low can you go” where 50 RPM is 3km/h, it’s more relevant that I can do say 5 km/h at 70+RPM (have not done any maths there, random numbers).

Certainly I find steep techy stuff much easier on the MTB if I select a gear or two lower than I think I’ll actually need (I have 32-52 on that). On the road it’s a bit different, as you can just stand on the pedals and effectively trackstand if you need to.

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Here’s another example. I usually ride this at 3.5-4mph on my MTB, or 2.5mph on my fatbike in the snow. It’s rideable in the snow only when the conditions are right.

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