The gearing is not the primary reason bikes are more efficient than unicycles going uphill, although it’s the reason bikes are able to be more efficient on many different types of grades. A single-speed bike will still beat a unicycle up Mount Diablo.
There are two main reasons bikes are more efficient than unicycles when climbing:
They go straight. Unicycles don’t.
It takes almost no energy to balance on a moving bicycle; balancing on a unicycle requires constant energy input. All else being equal, 50% of the time that energy input will be to slow the unicycle down.
Top unicycle riders get very good at minimizing the energy required for balance, but it’s still huge compared to bikes moving at appreciable speed.
If you need a demonstration, push a bike downhill. It will keep going until it runs into something. Now try that with a unicycle.
I’ve ridden up Mount Diablo on a unicycle with clipless pedals. It actually was the slowest time I’ve posted on the climb. Partly that was because I wasn’t really comfortable with them, and probably was too tense, but I think the potential benfit of clipless pedals to unicyclists is fairly small, even leaving out the face-smashed-in factor.
A bike with rubber platform pedals will still beat a unicycle up Mount Diablo.
I would have to side with our vehement Mr. Tholub here. I was a seasoned biker, road and mtn, before becoming a devoted unicyclist. In addition I’ve entered several up-mountain bike races on my uni. From a lifetime of competitive, highly aerobic sports, I’m very fit. The winning bike time in my better bike races was less than 2/3 of my best, even after I could uni efficiently.
Even stronger evidence is the aforementioned Mike Tierney, aka AspenMike from these fora. He’s a king of distance and mtn uni riding. In 2005 he (and two other unis) entered the granddaddy of hillclimbs, Mt. Washington, in New Hampshire. Mike lives at high-altitude in Colorado, and writes up his rides here, like this one with 64 miles and 7400 vertical feet gained. He also wins the Natl. Uni meet 10K races regularly. If anyone was poised to kick ass at a hill-climb race, it was Mike.
And kick ass he did, CRUSHING the old uni record by 30 minutes, finishing with a time of 1 hour 45 minutes 27 seconds in the 7.6 mile, 4700 ft. climb. I couldn’t imagine anyone beating that time on a unicycle. Of course someday it will probably happen, but Mike’s time won’t ever be beaten by much I’d bet.
Mike, with his god-like effort, was 399th out of 600 racers. BTW, the MW bicycle record? 49 minutes 24 secs.
The handlebars are out of line with your leg efforts, making any pull you can generate less effective, and you are already leaning down on the bars. Observe, as you suggest, a cyclist going uphill. He is leaning forward, therefore placing weight onto the handlebars, rather than being able to use them to really press harder on the pedals.
No? The amount of force you can apply to anything going up a hill is the limiting factor in how fast that object can be pushed up a hill. Schoolboy physics. Work= force times distance. Work is how much energy you put in. All you are doing when going up a hill is converting that to gravitational potential energy. The quicker you put energy in, the faster you climb.
Total rubbish. No reasoning at all to back up your statement. What you are trying to say, rather badly, is that on the flat, or on a slight incline you can achieve greater speed ( momentum) on a bicycle. This is entirely due to its gearing. the ratio of road speed to pedal revolution speed. Had you read my post, you would have seen that, in order to try to make fair comparison between the machines. I had created a situation where the gearing was identical. As regards all the weight on one pedal, you will observe bikes leaning from side to side as the riders work hard. All they are doing is stopping the bike from falling over as they pedal by leaning the bike. Unicyclists when pedalling up hill and working hard will similarly lean so as to try to keep their C of G central. By doing so they help keep their path straight.
To suggest the unicycle would turn 90 degrees is codswallop. You are doing other things to keep it going straight. If you had 75% on one pedal and 25% on the other, two 25%s cancel. So as regards total forces on the unicycle it is similar to having a rider of half the weight. Why wouldn’t he also turn sharp right? Do the same for 80/20 or 70/30. How much of your weight do YOU place on each pedal?
How would anyone ever ride one footed? Your “observation” would suggest the unicycle would immediately turn right. It doesn’t because the one foot rider is also doing other things to correct the track.
Observation? OK I observe, in so many threads, that unicyclists have stated that they pass bikes on the uphill sections. Which clearly demonstrates that in some circumstances they can ride up hills as fast or faster than bikes. The circumstances are probably steep hills.
Onetrack for instance said: unicycles are much faster for climbing.
while your body position above the cranks is very similar to a standing biker, but all your weight is on the pedals, some of the bikers weight is resting on the handlebar. less effort is lost in the drive train of a unicycle.
Redwelly said: But uphill seems much harder on a bike than a unicycle - even a 36er with short 102mm cranks. Everyone seems to describe passing bikes uphill on unicycles. and also said: Is it the geometry of a bike (less upright than a uni, so using less body weight on the pedals?),
Their observations seem to differ from yours. What makes you right and them wrong? Note also their comments abour weight on pedals.
My analysis is admittedly theoretical, and based on the very simple physics involved. But in working through problems like these you do need the base science to underpin anything else to wish to say. The posts in this thread are all over the place, they refer to rides that are up and down, 18 miles long, they discuss distance, gearing, crank lengths, downhill bits, they make statements in profusion that do not hold up scientifically. They give their own personal experiences in a particular situation, on a particular ride, little reference to the steepness of the hills. They throw in irrelevant detail like how good the rider is. They mention 64 mile long races with 7400 feet of climb. No mention of the fact that the 64 miles will contain a lot of flat road, some shallow hills allowing gear use, and even downhill sections allowing speed and even resting for the bikers, all in all giving the bicycles a clear advantage over much of the course. Not a good basis for establishing hill climbing effectiveness. So no, when discussing hill climbing efficiency it is not “nuff said”. It is hard to establish anything from such a profusion of different experience and situation.
To compare things scientifically you need to create a fair test, with all other things equal. I merely put the two machines, side by side on the same hill, with the same rider, same gearing, same crank length.
Over a 64 mile, variable terrain route of course Armstrong would beat Holm.
But now pitch Holm against Armstrong on a short, steep, constant slope hill, and you might find the results interesting.
The handlebars are out of line with your leg efforts, making any pull you can generate less effective, and you are already leaning down on the bars. Observe, as you suggest, a cyclist going uphill. He is leaning forward, therefore placing weight onto the handlebars, rather than being able to use them to really press harder on the pedals.
No? The amount of force you can apply to anything going up a hill is the limiting factor in how fast that object can be pushed up a hill. Schoolboy physics. Work= force times distance. Work is how much energy you put in. All you are doing when going up a hill is converting that to gravitational potential energy. The quicker you put energy in, the faster you climb.
Total rubbish. No reasoning at all to back up your statement. What you are trying to say, rather badly, is that on the flat, or on a slight incline you can achieve greater speed ( momentum) on a bicycle. This is entirely due to its gearing. the ratio of road speed to pedal revolution speed. Had you read my post, you would have seen that, in order to try to make fair comparison between the machines. I had created a situation where the gearing was identical. As regards all the weight on one pedal, you will observe bikes leaning from side to side as the riders work hard. All they are doing is stopping the bike from falling over as they pedal by leaning the bike. Unicyclists when pedalling up hill and working hard will similarly lean so as to try to keep their C of G central. By doing so they help keep their path straight.
To suggest the unicycle would turn 90 degrees is codswallop. You are doing other things to keep it going straight. If you had 75% on one pedal and 25% on the other, two 25%s cancel. So as regards total forces on the unicycle it is similar to having a rider of half the weight. Why wouldn’t he also turn sharp right? Do the same for 80/20 or 70/30. How much of your weight do YOU place on each pedal?
How would anyone ever ride one footed? Your “observation” would suggest the unicycle would immediately turn right. It doesn’t because the one foot rider is also doing other things to correct the track.
Observation? OK I observe, in so many threads, that unicyclists have stated that they pass bikes on the uphill sections. Which clearly demonstrates that in some circumstances they can ride up hills as fast or faster than bikes. The circumstances are probably steep hills.
Onetrack for instance said: unicycles are much faster for climbing.
while your body position above the cranks is very similar to a standing biker, but all your weight is on the pedals, some of the bikers weight is resting on the handlebar. less effort is lost in the drive train of a unicycle.
Redwelly said: But uphill seems much harder on a bike than a unicycle - even a 36er with short 102mm cranks. Everyone seems to describe passing bikes uphill on unicycles. and also said: Is it the geometry of a bike (less upright than a uni, so using less body weight on the pedals?),
Their observations seem to differ from yours. What makes you right and them wrong? Note also their comments abour weight on pedals.
My analysis is admittedly theoretical, and based on the very simple physics involved. But in working through problems like these you do need the base science to underpin anything else to wish to say. The posts in this thread are all over the place, they refer to rides that are up and down, 18 miles long, they discuss distance, gearing, crank lengths, downhill bits, they make statements in profusion that do not hold up scientifically. They give their own personal experiences in a particular situation, on a particular ride, little reference to the steepness of the hills. They throw in irrelevant detail like how good the rider is. They mention 64 mile long races with 7400 feet of climb. No mention of the fact that the 64 miles will contain a lot of flat road, some shallow hills allowing gear use, and even downhill sections allowing speed and even resting for the bikers, all in all giving the bicycles a clear advantage over much of the course. Not a good basis for establishing hill climbing effectiveness. So no, when discussing hill climbing efficiency it is not “nuff said”. It is hard to establish anything from such a profusion of different experience and situation.
To compare things scientifically you need to create a fair test, with all other things equal. I merely put the two machines, side by side on the same hill, with the same rider, same gearing, same crank length.
Over a 64 mile, variable terrain route of course Armstrong would beat Holm.
But now pitch Holm against Armstrong on a short, steep, constant slope hill, and you might find the results interesting.
As a keen cyclist who’s recently got into unicycling…
Sam may be faster on a unicycle than on a bike, but I think it’s only because he’s a much more experienced unicyclist than bicyclist (from speaking to him on the few times I’ve met him - please correct me if I’m wrong, Sam).
I would agree with most of the posters in this thread - given the same class of rider (on the respective machines), a bike will always be quicker. There may be exceptions in rare cases like very steep slippery off-road climbs where the unicycle has the advantage of staying upright and having more traction. A very good unicyclist who isn’t expending too much energy balancing may have the advantage of the lighter weight of the unicycle on a long climb, but that’s assuming the gradient is just right for whatever gear the unicyclist happens to be in - the bicyclist can pick a gear to suit (unless they’re weird like John ;))
Personally, I’m MUCH quicker on a bike than a uni, but I’m not much of a road unicyclist, Sam is. I quite commonly catch and overtake bikers on my cross-country uni commute, but that’s not because unicycles are faster than bikes, it’s because there are a lot of pretty slow cyclists out there.
On a related matter - I’ll attempt things off-road on a muni that I would probably chicken out of on a bike, especially very steep downhills. I feel much safer on a unicycle - it’s much easier to bail out and land on your feet if things go wrong, whereas on a bike there’s much more chance of ending up headfirst and tangled in bits of machinery.
I get your point, it should and probably is a bit less efficient, but I assure you that a cyclist climbing with good technique is really heaving upwards on the bars. There certainly isn’t any weight on them. Part of it is that the slop of the hill reduces the forward lean, part of it is that you pull on the bars while on the lower, backwards part of the pedal stroke (I think - I’m trying to explain my experience of climbing on bikes, it sounds about right but could be wrong.)
True, but that’s at any one point. On a bike you can use gears such that you put in your maximum sustainable effort. The force you apply at any one time might be lower, but by keeping it up you are faster up the whole climb. Obviously if a unicyclist can keep up the effort required to keep moving comfortably, they might be faster - hence unicycles overtaking bikes on some hills, when the gradient is about right. Sadly when the gradient changes, the unicyclist can’t adapt to the change as well as a bike.
I agree.
It’s always a problem with science though - sometimes to make sense of a problem you have to simplify things, but it can be very difficult to be certain that the simplifications you make don’t remove the factors that make a difference. The nature of science and science teaching is that “schoolboy physics” generally means “one set of lies that will sound about right, and will make the next set of lies easier to understand”.
I still say the reason a bike is faster uphill on average is that a biker can always choose a gear that is right for the hill, and a unicyclist might be faster uphill on a unicycle because there muscles are developed for unicycling, not biking. Sorry Sam, you’re still being a big jessie.*
John
*I realise that next time I see Sam, it will be for a unicycle ride, and I may regret this comment.
When unicyclists pass bikes on uphills they are passing bicyclists who are either less fit than they are or are much less enthusiastic about climbing hills as the unicyclist is. Usually it’s a combination of both. There are lots of cyclists who put only the minimum amount of effort in to climbing hills as they can get away with. They just don’t like hills. Those are the bicyclists you pass while unicycling.
I’d almost agree with this, but change it to “long, steep, constant slope hill” instead. Sprinting is much easier and faster on a bike than a unicycle; when standing up you’re in the perfect position to use your entire body, including pulling /up/ on the bars, to turn the pedals round. You just can’t sprint like that on a unicycle; you need to balance, you can’t use both arms (just one, and that’s not in a very good position), and you can’t fine-tune the gear to your preferred rhythm.
However you can’t sprint a bike for very long before having to sit down again, click down the gears and spin; this is where the unicycle will start to catch up and go past because of the weight advantage and better position while sat down for power output.
On most longer routes of ups and downs the bike will win; on short uphill sprints the bike will win, but on longer uphill drags the unicycle has the advantage.
That’s a key thing about bikes. As you’ve stated, in both cases there’s a maximum force you can put in. However, on bikes, you can tune the distance by pedalling faster in a lower gear. By simplifying out the gears, you simplify out one of the key things that makes it easier for bikes to climb hills. That’s just one reason schoolboy science isn’t confirmed by actual real world findings and no unicycles are winning hill climbs in major races.
It’s not surprising that people like Sam pass bikes often, they’re probably way way fitter than 99% of the population on their bikes. I don’t think even Sam passes road bike club runs often (given his averages are below the 20mph average that’s a normal club speed), and he is for sure fitter even than almost all club cyclists.
I think there’s also something you’re misunderstanding about the body mechanics involved, in terms of the thing about the difference between pulling up on the handle, and holding onto the bars. If you ride a bike up hill, you’re forward to keep the weight front, but you’re still pulling on the bars to hold yourself on the pedals (if you’re in too big a gear to sit back and spin).
As yet another anecdote, I rode a 68" geared fixy a couple of months back and went up some hills that I know I can’t do on a coker because I’ve walked up em. I’m alright at riding unicycles, and okay on a bike too, probably 8-10,000 miles on the unicycles, something around that on the bikes (before I got the unicycles).
Do you really think that a 70" unicycle (even with 170mm cranks), would get up many steep hills, like the lakeland passes? Fixed wheel bike riders get up them all the time, and tend to use silly gears like 70" or more.
I was thinking about this the other day when I passed a gang of weekend MTB heroes in the woods.
Firstly lets look at the science. Unfortunately we have to ditch schoolbook physics here in the real world, there are no point masses & inextensible strings. The friction & efficeny losses are going to burn us every single time. It might well be the case that you can put more force into a unicycle, but a bicycle is a much more efficent machine, as tholub and a couple of others have said you can tweak them more than a unicycle & unbalance your equation.
So if a unicycle is less efficent (and lets face it it has to be, if only because as a unicyclist you have more air resistance to deal with) why do we keep on passing bicyclists ?
Simply because an average unicyclist is a better rider than an average cyclist. If I go for a 6km ride on my uni I have to pedal every centimetre of that 6k, how many cyclists do that ? We are in the main more used to using our muscles than the majority of cyclists because we have to do it more. We can inefficently brute force our way up various slopes in a way our two wheeled friends don’t need to (and so don’t)
A B*** is a more efficent means of transort than a uni sorry & all but it is, nowhere near as much fun though
I love you as much as someone who’s never met and knows nothing about a person could possibly love that person, but…
My post was refering the the 64 mile ride only as one of the strengths on Mike’s endurance resume. My example of the Mt Washington hillclimb is however, a solid, pertinent example for this thread, and not “all over the place.” Mt Washington is 7.6 miles, nearly a mile of climbing, and every bit is uphill. That’s the key. So, with that in mind my observation must carry more weight than you granted me in your ignoring it. The bolded portions of my quote below are hard to refute.
So, to recap, one of the toughest of uphill climbs in the business, and Mike, one of the best uni-riders suited to such a race, was beaten by 398 bikers.
Re: Why are hills hard on a bike? (unicyclist perspectives)
On Tue, 30 Jan, Naomi <> wrote:
>
> tholub wrote:
> > 2) Downwards force on the pedal is not the limiting factor in hill
> > climbing…
>
> No? The amount of force you can apply to anything going up a hill is
> the limiting factor in how fast that object can be pushed up a hill.
> Schoolboy physics.
Your schoolboy is forgetting some stuff.
Principally, that bicycles and unicycles are human-powered vehicles,
and the limiting power available has very little to do with mechanics
and everything to do with physiology. It’s heart and lungs that limit
sustained power output, not force generated by the legs. The limiting
factor in how fast you can go up a hill is how fit your
cardio-vascular system is, not how hard your legs can push the pedals.
(This is why the occasional crackpot inventor that thinks they’ve made
a faster bike where you crank with arms as well as legs is merely
rehashing old mistakes - the sustained power you can get from your
legs alone is at least as great as you can from your legs plus your
arms, unless you have particularly unusual body (like, one without
legs).)
A bike more effectively utilises the power available from a person on
most gradients.
Look, the premise is absurd. You can’t go faster than a bike uphill with a unicycle. Maybe you could pass little old ladies who have single speed cruisers or middle aged yahoos who don’t know or even think about changing gears, but an average cyclist with a road bike who actually knows how to change gears and ride, no way.
I’ve got a 29 and a 24 and there are roads here around the mountains here in Phoenix that I can’t even climb on a uni whereas on my bike I can still do it.
When it gets too steep, you end up having to put more than your body weight on the pedal stroke and push the uni from out under you. You could hold on to the seat with your hands to apply more pedal force but you lose a little balance and it only works a little bit. Try it on a one mile climb up a steep grade where you have to hold on the whole time… Maybe up a short hill you could do it but for a long period of time no way. And in these cases you’d be going faster by walking anyway.
On a bike not only do you have access to lower gearing to increase your effective pedal force but you can easily hold on to the handlebars and put more than your body weight onto the pedals.
As far as speed goes, sure if your in good shape you can beat a loser on a bike who doesn’t know how to ride it well. But even if the guy had a single speed with the same gearing as your uni, he’d have an advantage due to being able to use the handlebars.
Right, that’s it. The only way we’re going to sort this out is a race.
Sam can tell everyone the course, presumably a circular route from Aber; competitors can either race on a big-wheeled unicycle, a road bike or a mountain bike. Geared unicycles or singlespeed bikes gain bonus points for helping to remove variables from the equation.
There already are races. Have Sam come out and do Mt. Washington this August. That’ll show all those bike-weenies who’s boss. It’s not far from you guys - it’s on the East coast of the US, after all. Bring Naomi.
yeah, but how about you race a single speed, 1:1 gear ratio bike w/ no freewheel and a unicycle. that would be the most feasable race I have seen in this whole post
but lets just say you are racing those exherting the same force on the pedals, the unicycle would win, only because the chain has to stretch and has friction, as well as the friction that the front wheel causes.
