DaveLeeNC

In principle I will be taking on some long and steep climbs in a couple of months. And the question of gearing is still on my mind.

In my case it seems to me that, assuming that I am putting out power somewhere in the range of my ftp, that a cadence down in the 70 to 75 range is where things start to become inefficient. I think that I could pedal at 80 rpm or 95 rpm (at around my ftp) without making a huge change in physiological effort. But somewhere in the 70 to 75 rpm range and (at the same power output) I will find that the time that I can spend at roughly ftp is going to go down. And things go downhill (as in harder to maintain) pretty quickly in a very small rpm range. E.G., there seems to be a huge difference between 67 and 72 rpm.

What have others found about this in their riding. I am just curious. A new RD (or not) for my bike is driving this question.

Thanks.

dave

ps. It is a difficult experiment to run in my case because I just don't have any climbs that are long enough to test this (everything around here is up and down constantly, so constant power/rpm is not something that I can achieve on our roads).

dave

DrIsotope

If you're that sensitive to gearing selection, and are apparently planning on going up a series of hills at full throttle, you're going to need gearing to accommodate.

On proper climbs (that is, Cat1 or HC) my average cadence is pretty much always in the 70s-- but I only know that from post-ride analysis. I'm never looking at it during a 9 mile long climb that gains 2,900 feet.

As long as I'm upright and moving forward, my cadence is fine.

TimothyH

If pedaling is faster than walking then I pedal.

If walking is faster then I walk.

There are always some single speed riders at gravel events. These struggle up some of the longer and steeper climbs but I've heard it said that when riding is slower than walking it makes sense to get off and walk, otherwise ride.


-Tim-

DaveLeeNC

Is that cadence just a unconscious choice, or is it what you are stuck with because you don't have a lower gear?

Thanks.

dave

terrymorse 

I've noticed a few things that influence my preferred cadence on climbs:

• When I'm using more power, my cadence is higher.
• When the grade is steeper, my cadence is lower.
• Grade has a stronger influence on cadence than power.

From a few recent rides:


Comparing climbing cadence and power for several road grades

canklecat

I'm usually a 90 rpm spinner, like clockwork. I might slow my cadence on some climbs, maybe 75-80. But that's on my older bike with downtube shifters. I need to put some cadence and speed sensors on my carbon bike with brifters and see if I ride differently. I know with the steel bike with downtube shifters I anticipate and shift well in advance because it's a PITA to shift while in the middle of a steep climb.

With the other bike with brifters I can shift while standing, which probably affects my cadence. But I won't know until I install some sensors and check. It's also at least 5 lbs lighter, which probably influences my climbing style.

I dislike mashing but I'll occasionally do indoor trainer sessions at 50-60 rpm in the highest gear I can grind. And, rarely, I'll do that on some outdoor solo training sessions. But in group rides I try to stick within in my comfort zone, which is usually 90 rpm.

During a 50+ mile club ride this weekend on a hilly route, after about 30 miles I found myself huffing and puffing on some climbs that would normally have been easy, and shifted to a harder gear and slowed my cadence way down. Helped a bit, although I can't sustain grinding at 50-60 rpm for long climbs. Fortunately we don't have any long steep climbs here.

I only realized later that my back, shoulder and intercostal muscles are really stiff and sore (old injuries from multiple crashes and being hit by cars), hindering taking full deep breaths. So I was panting, taking shallow breaths. Big hindrance. So I'm going back to PT and the chiropractor to sort that out.

DrIsotope

I have a 1:1 final, but am also usually around 95kg, so my cadence is as much a battle of mass vs. gravity as anything else. I don’t regard myself as anything of a climber.

canklecat

At 5'11" and 150 lbs I may look like a climber, but looks can be deceiving. Losing 10-15 lbs since last year makes climbing easier, but that hasn't translated to faster.

I don't work very hard at improving my climbing, though. We don't have any long enough grades, so all we can do is repeats.

I've tried tricking myself in to thinking some settings on the indoor trainer mimic climbing, but... nah. It doesn't. Only climbing is like climbing.

woodcraft

I also often have gears down to 1:1, and tend to climb the the 70s or 60s rpm even if lower gears are available.

AFAS ftp, I use a ~1/2 hr climb at 7% for a test as this is where I can put out the most power.

Is this more efficient than 100 rpm on the flat?

Partly the term efficiency is ill-defined and misleading, also grade, what you are trained to, fatigue, etc., etc. are factors.

Seattle Forrest

I'm on down into the 70s. It's maybe the 50s where I struggle. I'm not built like a cyclist. I lift heavy in the gym including lower and fill body lifts.

Carbonfiberboy 

78 is my "no lower, boss" climbing cadence. I can go down to about 74 before it becomes a bummer. Down around 68 I can feel my legs tiring and my power actually goes down a bit. 82-84 is nice. Folks with high VO2max should use a higher cadence than that. High cadence uses more oxygen, low cadence uses more glycogen. One has to find their own best balance. I have a couple decades of testing on long climbs behind me. Obviously I like very closely spaced low gears. My best range is quite narrow, best range meaning highest VAM for durations of 1-3 hours.

Jack Tone 

My normal cadence seems to be in the mid 70's. Once I'm warmed up I can ride in the lower 80's. Hard long climbs, on the trainer, at least, are in the 50's. I tried a cadence workout a day ago, and went around 90 for almost an hour. I didn't think I could ever get that high, and it hurt when it was over!

Dean V

Get the long cage derailleur and bigger cassette and be done with it.
Then you will have the gears and the option to use them.

CarloM

This just shows me how weak I am at climbing. Now in my second month into cycling after a 30 year absence. I can handle flats and slight inclines just fine. I did a 12.5 mile unbroken ride averaging 17mph the whole way, and it was slightly uphill for most of it.

But there was one 3000' stretch of it where cyclists have to leave the dedicated bike path and join the 101 freeway, and because of the way the on-ramp is you don't get to keep most of your speed that you'd been building up.

The first 1000' (onramp to the 101) is about a 6% gradient. The second 1000' is about a 3% gradient (but you'd already lost your momentum from the first 1000') and you have tons of freeway debris on the shoulder (which admittedly is very big so you never fear being hit by a car, there's just so much crap there). And then the third 1000' is about a 7% gradient (offramp from the freeway).

That 3000' is devastating to me. I probably average close to 18mph for the rest of the ride, but that 3000' stretch brings my average down one full point because of how slow I end up taking it. Out of pride, I refuse to lug, so I end up shifting to the lowest gear and trying to maintain the 60-70rpm cadence. With my 34 front and 28 rear I'm sure I'm basically going walking speed. By the time I get to the top my HR is basically near the max for my age (165-170) vs. the rest of the ride at 18mph it's around 145-150.

I've done that ride twice now, and was stronger the second time overall, but it made me work on sprinting and taking on inclines locally to try and up my strength for that stretch of climb. I don't know how riders do it on 10-15% gradients. That last 7% gradient absolutely blasts me.

Gives me a goal to work towards!

asgelle

I'm not sure what you mean when you say things start to become inefficient, but by context it sounds like you fatigue much sooner at those lower cadences. If that's the case, it could be that given the same power at lower cadence requires a greater force, around 70-75 rpm is where you need to recruit a large fraction of type II muscle fibers. These would produce greater force, but would also fatigue much sooner than the type I fibers needed for the lower forces at higher rpms.

Since fiber type distribution is highly individualized though may be affected by training, I wouldn't read anymore into it than this is the crossover point for you at this time.

RChung

That's a 7% difference in rpm. If you're really on the knife edge, decrease your power by 7%

HTupolev

That'll further slow you down and drop your cadence, largely cancelling out the attempt at reducing the required leg force.

The answer to avoiding gearing bottom-out is to get lower gearing.

DaveLeeNC

Just to reiterate what HT said (but in a different way), you can do that effectively on the flats. Drop your power output, slow down, the opposing force is reduced, and you can actually use a reduced pedal force (same gearing).

But going up a hill you are (for all practical purposes) just fighting gravity. So to go up a hill (at a given gearing) at any speed, you need the same force applied to the pedals. It is the same force that would be required to keep you motionless (ignoring friction and aerodynamics). More power means more speed, but it is all in the 'v' part of P =F*V. And, I speculate, it is the F part that is the issue that I am analyzing (and at some point it is an issue for any mortal biker).

Regarding the 'just get higher gears and a longer cage RD and be done with it', that is the question on the table. But all of this is about a single ride (Six Gap Century) and those extra gears are worthless to me where I normally ride so would actually be a detriment, taking away gears that would be useful to me. Since I seem to be on the edge of needing these gears, I am proceeding with caution. 34F/30 rear is what is my default without other changes.

dave

ps. In this 'analysis' I am assuming no out of the saddle stuff (and I don't find out of the saddle a particular issue). I am just holding that in reserve.

seau grateau

Climbing is hard no matter what you do.

HTupolev

Not really. With adequate gearing, you can choose exactly how hard or easy you want a climb to be.

And regardless of how easy or hard you're going, it's useful to avoid bottoming out the gearing. I'd much rather perform well while riding hard than perform poorly while riding hard.

Lemond1985

Last Sunday I was on a steep climb, in hot weather, really suffering. I thought I was in my lowest gear (34x28) but was actually in the next-to-lowest one (34x24). I actually had made the difficult decision to quit, after fighting with myself for the past 10 minutes. I could not go any further and complete the loop I had planned.

Just before my pulling foot out of the pedal, to stop and turn around, I saw my mistake and shifted into the 28. That one extra gear allowed me to continue and finish the ride. Without it, I would have had no choice but to quit. To me that's huge, compared to the loss of one gear somewhere else on the cluster.

I have never gotten back from a ride and thought, "Boy that low gear I had, but never used sure slowed me down." Much more often it's "If I only had a lower gear." Difficult to tell yourself that while sitting in a comfy chair at home, it's much easier to scoff and say, "Meh ... I'll never actually need THAT low of a gear."

colnago62

Gear selection and climbing style has a lot to do with a rider’s weight. The more you weigh, the lower your gears will probably be compared to a person who is significantly lighter than you. If you are not use to long climbs, I recommend that you select much lower gears than you think you will need. It is very difficult to recover if you blow up on a climb.

terrymorse 

Uh oh, I feel a movie quote coming on:



A League of Their Own, 1992

Carbonfiberboy 

You and HT are of course correct. I would add that we don't get younger. It might amaze you how soon you'll want that lower gear. Over the years, gradually moving to lower and lower gears, I have so far never had a gear I didn't use. You might find you really like to spin a little faster on the climbs when your legs start giving out. That's been my experience. A bit counter-intuitive at first, but not after you've thought about it a while. When I really get whupped, I'll find myself doing short climbs at 95. Same match of leg and lung I was talking about earlier, but now with the legs being the loser, not the lungs.

Dean V

I can't see how you expect other people to know how well you will cope with pushing a larger than optimal gear for extended periods of time?
Personally I know I can cope with grinding up a hill for maybe 15 or 20 minutes. But for long climbs like you are looking at ( 30 min plus) if I don't have a low enough gear it starts to get ugly.
Maybe you will manage, or not. There is one way to find out