EvilWeasel

I dont care how many grams lighter your bike is than mine... I'm 80lbs lighter than you, and we are both in excellent shape. I will always win when fighting gravity.

jyl

I don't think short chainstays, steep head angles, etc matter when climbing your basic paved 10% grade. That stuff matters when traction is poor, like on the dirt or on really steep pavement in the rain.

I also climb about the same on my Cannondale R1000 vs my 753 Raleigh. One very stiff, one on the flexible side.

Wider handlebars help if you climb out of the saddle and like to rock the bike from side to side-by-side, which may not be the best idea. For me, having full leg extension matters. Some people say they have trouble going from seated to standing if a bike has a certain geometry, which I can't fathom.

Otherwise, as long as the bike is light and has the gearing you need, the rest is up to you.

So, how much does "light" matter? It clearly matters some. 2 lb is 1% of the weight of a bike plus a big-boy ahem plus-size errr fatty-pants rider. Like me. I think you can feel 1% when you are suffering, even if 1% is negligible when you have energy to spare. But it is easy enough to experiment. Climb a hill, then climb it again with two full water bottles.

And then there is psychology. Knowing your bike weighs only XXX pounds may make you more confident. Climbing is as much a trial of the spirit as of the legs.

mountaindave 

+1 "I think I can, I think I can, I think I can!"

southpawboston

This has been somewhat debunked, at least for people who prefer a high pedaling cadence. A flexy BB reduces the height of bi-phasic torque peaks during a revolution of the cranks and helps spread those peaks out more (imagine two peaks on a graph: one tall and skinny, the other short and wide; they both have the same peak area representing total power output), reducing strain on the rider's legs and knees. This phenomenon (which Jan Heine refers to as 'planing') seems to hold pretty true for me, as the best climbers in my fleet are the ones with skinny tubing and flexy BB, despite any differences in weight. During steep climbs with these bikes, my legs don't feel as strained and I'm more limited by my cardiovascular shape than my leg muscle tone. On rigid bikes (like a couple of touring bikes with stout tubing that I've ridden), my legs give out long before my lungs do.

The concept of 'planing' may not hold as much validity for those who prefer a very slow cadence, where the torque peaks tend to be less sharp and more distributed throughout the crank revolution.

dddd

Is that from this thread? Can you perhaps cite what anyone said to this effect?

Regardless of geometry, one is free to set the saddle and handlebar positions just about anywhere, using the right parts to get the fit that they want. But the frame's geometry may not "support" a particular rider's fit choices by still handling as it should, so in this way the frame's handling is directly related to the fit parameters, i.e. the frame's geometry.

Chrome Molly

A high cadence tends to be more fore and aft energy vs downward pressure. A flexy frame tends to flatten out the peak pressure on the quad as you start forward before top dead center (flexes slightly out of the way). A tiny bit more or less flex is noticeable on the knees. Spinners tend to be ok with a degree of flex.

The best "mashers" tend to use a slow pace and also some calf to accelerate the crank across the bottom, clearing tdc so they mash mainly downward during their peak power phase. Those riders tend to prefer stiff frames.

So "fit" is a matter of both size and style.

noglider 

There are obvious factors, rider weight, bike overall weight, wheel/tire weight. Those probably account for most of it. But some bikes climb better than others, and I can't put my finger on it. I'd say fit is a big factor, and I believe that being able to move your weight forward (if you climb out of the saddle) helps quite a lot.

In late December, I visited my inlaws on Bainbridge Island. I was able to borrow my sister in law's brand new Trek Domane or whatever their latest high end model is. The hills there are steep, and that bike made the climbing super easy. The light weight was an obvious factor, but I think the geometry helped, too, though I didn't analyze it to figure out how.

dddd

I think someone touched on this already, but the way some bikes steer (the way that the steering behavior magically keeps the bike centered under the rider without inducing tire scrub) makes for an effortless feel that exploits the riders efforts in making uphill progress.

I usually associate such steering feel with steeper-angled frames.

And can it be that shorter chainstays effect less leverage of pedaling side-load forces in pushing the front end around?

I'm never so sure how much that an efficient feel translates into any actual increase in climbing speed, but it does tend to boost one's confidence when bridging gaps and such.

When climbing at the limits of sustainable power output, very small increases in power output can cause very large increases in cardiopulmonary stress, so even just a small difference the weight of the bike can have a seemingly disproportionate effect on perceived effort when a certain pace is to be maintained in keeping up with, or ahead of, closely-matched competitors.

noglider 

I think I'm going to measure the top tubes and reaches of my bikes. I suspect a long top tube or reach or both help with climbing. @dddd's comments above make me consider this.