I’ve been riding for long enough to know that what “feels” good and and what “is” good in terms of technique are two independent sets with a small intersection; it’s very important to put a lot of thought and research into what you’re doing to make sure it offers a benefit. Research takes “work” and “time”, so I’m not very fond of that approach. Instead, I like to do a lot of “thinking”, leveraging both my inadequate expertise in mechanics and my unusually high degree of confidence in my ability to reason in order to jump to conclusions that benefit my initial assumptions.
For example, I believe there is an advantage to riding sur la plaque, or in the big ring, as opposed to riding in the same size gear on the small ring. I generally find that when I’m strong enough to stay on top of my gear, climbing in the big ring feels less cumbersome than when I climb in the small ring at the same speed. The downside is that it is like playing a game of chicken with your legs; it works very well if you are able to keep the gear turning over smoothly, but should you fall behind the gear, and your speed evaporates as you fall into a spiral of downshifting and decreasing speeds (not to mention morale).
All this can be explained away by having good legs or not (un jour sans), but I think there is a mechanical advantage as well.
First, there is the duration of the effort. As they say, it never gets easier, you just go faster, but I firmly believe faster is easier, provided you are strong and fit enough to support the effort. The faster you climb, the less changes in gradient and road surface impact your speed. Not to mention that while all athletes perform the same amount of work when they cross over the same climb regardless of the duration of their effort, athletes doing so in less time suffer for a shorter period of time than do those who go slower. Marco Pantani claimed that despite knowing the suffering that was just around the corner before his attacks, he was motivated to go as fast as possible in order to make the suffering end sooner.
Second, there seems to be a mechanical advantage of riding in the big ring. I’m a little bit hazy on the physics here, but it seems to me that the crank arm is in effect a second-class lever and, while maintaining the same length crank arm (lever) and fulcrum (bottom bracket), by moving into the big ring, you are moving load farther out on the lever, providing a mechanical advantage over the small ring.
WikiPedia defines leverage as:
load arm x load force = effort arm x effort force
In our case, since the speed is constant, that means that the load force (to turn the pedals) is also constant. And, since the load arm (crank) is a fixed length and the effort arm length is increased when moving the chain to the large chainring, the effort force is reduced in order to maintain a balanced equation, meaning that it doesn’t just feel good to ride sur la plaque, it actually is good.
All that said, this theory completely ignores the energy loss of bending the chain as you start to move the chain from straight at the center of the cassette towards the edge of your cassette, in particular when riding in the big ring and crossing to bigger cogs. Q-Factor has an impact on how much your chain is bending as you ride in bigger and bigger cogs, but I think there’s a measurable loss if you are crossing your chain completely (big ring to biggest cog); and I suspect is is entirely possible that the big ring’s mechanical advantages are outweighed by losses in chain friction.
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You are contradicting yourself every time you counteract my points!
"You want the gearing that will allow you to turn over the pedals smoothly and efficiently."
So if that means I have a 10% or a 15% grade to climb, and I am nowhere near as strong as a Pro, then that means a compact will allow me to turn the pedals "smoothly and efficiently". Remember, I'm talking about the difference between a 39t and a 36t ring, i.e 3 teeth. That's the same 3 tooth difference between the old standard 42t and a 39t.
"Science has shown that high cadences on climbs is better than the old, slogging, climbing we saw 20 years ago with the 42."
Correct! Same goes with a 36 over a 39 up a steep grade. If a rider can't sit and spin in the 39, it means getting out of the saddle and grunting it up and rocking from side to side a la Cadel, but without the obvious power advantage he has over us mortals.
"And, as I mentioned, if the Velominati are about style and aesthetics, then they have to be for the 39, since climbing in it is far more graceful and elegant."
There's nothing graceful and elegant about barely turning the pedals at walking pace, is there? And if we were only about style and aesthetics, we would be riding steel frames with quill stems and downtube shifters. But we're not. we are living in a modern world of technology, and that includes compact cranks, whether you like it or not. No-one is forcing you to ride one, just as no-one made you buy a carbon frame, or STI shifters, or 10 speed gruppos.
The fact is, you don't like compacts. That's cool. But to use the defence of "it's not aesthetic, it's not traditional, it's not beneficial" well that is just flawed logic.
@brett Marvelous. But, Brett, you wound me more deeply here than on anything else: "that is just flawed logic." I'm pretty much following Jarvis here.
@david Yikes, that wasn't supposed to go out yet. Err, I'm pretty much following Jarvis here. I think what he's said on the issue is exactly right. Put lower gears on your bike, and you will go slower. True, you want the gears that will allow you to turn over the pedals smoothly and efficiently. But the issue is about your potential. ProTour riders aren't going to try to climb Mortirolo in a 39x19 gear, hoping that eventually, they'll master the gear on the climb. It's just too steep. And they are at, or near, their potential anyway. But for a mortal human being, mastering a 39x23 gear on 5% grade is quite possible. If, initially, you struggle, by following Rule 5, you'll eventually master the gear, and be able to ride the climb with a smooth, efficient pedal stroke. So, I guess the issue is this.
A. You can start a climb, initially, looking for the gears that will enable you to climb it smoothly and efficiently, or,
B. You can start a climb, with gears that are hard, and get stronger, so that you can eventually climb it smoothly and efficiently.
I speak here from personal experience. I'm in a place where you have to climb out of it to get any decent miles in. I started doing the climb, thinking, Damn, I need some climbing gears. Three weeks later I mastered the gear I initially started climbing in. I HTFU, and mastered the gear.
Damn, I've been promoted to Level 1 status. That's cool.
Damn, I've been promoted to Level 1 status. That's cool.
@brett says, "The fact is, you don't like compacts. That's cool. But to use the defence of "it's not aesthetic, it's not traditional, it's not beneficial" well that is just flawed logic." It's not beneficial for budding young cyclists, or for those who've not already spent years and years climbing. Absolutely no doubt about it. Let's examine the particulars. Again, young Nathan has a 5% grade of some kilometers. Come on. Honestly, do you think putting him on a compact, to climb in a 34x25 is better for him than telling him to go out, HTFU, and master the gear in 39x23?? Nathan can master the climb in a 39x23, eventually, I'm positive. The only grounds you could have for saying the compact is better is that it is easier. Fuck that. Rule 5.
By your logic, the Pros who climbed Cojones with compacts should've just HTFU and used bigger gears?
I never said a compact was 'better', but I did say it is valid. And it is. I'm sure Nathan probably climbs that 5% grade in the 50 anyway.
Congrats on your Level 1 status too bro... you climbed up to it so quickly you must've been compacting your posts!
That's enough with the charge of contradiction! You cannot imagine how painful that is. A contradiction is a proposition, P, and it's negation, ~P. E.g, Compacts are wonderful & It is not the case that compacts are wonderful. To charge someone with a contradiction is to claim that their statements entail P and ~P. To make the case for a contradiction, you have to show what statements entail a proposition, P, and its negation, ~P. You have not done so. Please refrain from the charge until you have discharged your burden.
@david
congrats on Cat 1 status.
@brett @david
compacts are not valid if you want to maximise your performance, they make you slower. So many times I have heard people new to the sport or coming across from mountian biking who say they need a triple/compact to get up the "hills" (in this context "hills" are short <10% gradients). No they don't, they just need to realise that they can get up them, it's mostly in the head and that eventually it gets easier.
To race, you need power, you need to be able to push 53x12 on the flat, and you won't get that from a compact. With all entry-level race bikes sold with compacts and triples anyone starting racing on a budget is at a disadvantage.
Besides, the shifting is all over the place and compacts don't look as aesthetically pleasing.
Yes, the ratio of the big ring circumference to the small ring circumference on a compact is just grating on the eye and mind Good point.
*snigger*