It is "Festivas" today,celebrated by heated arguements while sitting around a pole.

You forgot about climbing. There's a big clipless advantage there.

Ok, what is the big clipless advantage there?

Not "clipless" per se, but the point is a secure pedal connection. Despite you and some people's protestations to the contrary, you really can pull back and up through the pedalstroke which is very beneficial during sustained climb at threshold effort.

So basically, the largest advantage, with clipless, is to be able to "go nuts" without worrying where your feet are on the pedal... I won't argue with that.

However, the pulling up phase of the pedal stroke isn't going to and just can't generate much power when compared to the downstroke, simply because of the muscles involved(hip flexors and abdominals). I'm not sure why people think this is particularly so advantageous on a climb? Perhaps people exert themselves more on a hill, something not really specific to the grade of the road itself, thus clipless are an asset to keep their feet on the pedals. As for the "pulling back" part of the stroke that is also done on platform pedals with correct technique.

do you not have hamstrings?

There is a lot of free "literature" available discussing pedaling technique and I can assure you that a clipless pedal system is going to be more efficient in every scenario you can present to me.

Yes, i have hamstrings.

The trouble with such "free literature" is that it has rarely been reviewed by an expert.

If you don't think that Joe Friel is an expert on cycling then I'm not really sure we have much to discuss.

Someone correct me if I'm wrong on this:

Even if it is true that you can't produce any significant amount of additional power by pulling up on the pedals, I'd hypothesize that with the motion of pulling up, a clipless rider will be able to remove more weight from the ascending pedal than a rider on platforms. The rider on platforms will have to keep his foot planted in the correct position, and this results in a certain amount of pressure resisting the upward motion of the crank. If the rider is free from this concern and able to totally unweight the ascending pedal, more of his effort will be used in moving the bike forward.

So, whether there is an increase in overall power due to the upward motion or a decrease in wasted power, the net result is more power going to the ground.

Ok, well then we probably don't have much to discuss... I did find this on that page

"Efficient cyclists slightly unweight the pedal on the recovery side, or backside,"

Not exactly an endorsement for power generation some clipless advocates are making it out to be.

It's true with platforms there is no "pulling-up", but a good rider can keep his feet on the pins and aligned while not weighting the pedal. I'm not sure how much resistance pushing the pedal up offers, if anything it will slow the cadence a bit. If you look at the numbers i posted previously though, you can get really good cadence on platforms.

Another benefit of clipless, which nobody pointed out, is that you can get on the gas a little bit earlier at the top of the stroke. Again, no huge improvment though.

I don't forcefully lift my foot on the upstroke, I don't think very many people do. There are studies that indicate that's not the benefit of using clipless pedals. It's not just about the upstroke, and there is literature that states this.

Thanks for the studies, i will take some time to read them later...

Perhaps you don't pull-up but a few people do... umd just wrote this:Again i do think clipless can enable more efficient pedaling, just not 20% or whatever some previous posters claimed.. I would say it is on the order of 3-5% perhaps, depending on your skill

When it comes down to the final 600 meters, I'm about to pull my thigh out of my knee-cap. Just to clarify. As for the hills, I'll refrain from commenting due to my geographic location.

Here's an idea. Go find a steep-ass hill. So steep that it shouldn't even be paved. Pick a gear that will have you at 30rpm going up it with a hard effort. Clip in with normal cleats/clipless pedals, and climb the hill at 5x interval pace (like you could just barely do that pace 5 times). Ride back down and change into running shoes. See if you can match your previous time, with any level of effort.

(Hint: you can't)

It has nothing to do with "going nuts." I said sustained and threshold.

It is especially helpful for climbing because there is more penalty at the dead spot in the pedalstroke if you don't pull up with your hamstrings to keep the momentum. Maybe the power isn't generated by the upstroke, but without the contribution it is much more difficult to generate and sustain threshold power. I'm not sure what your qualifications are here, but I've done millions of feet of climbing and have done much experimentation on the sibject.

I'd like to take back my hill comment because in both cases (sprinting, or climbing a hill) I can't imagine giving it a full effort without picturing myself face planting on my stem on platform pedals.

From what i've seen and experienced more power is to be gained by blasting and focusing on that down-stroke...

Yeah, that is why you learn how to determine and select the correct gearing for the hill... I get what you're saying though, and i've already said clipless shoes help to keep your feet on the pedals.

From what I've done, whatever the heck it is I'm doing works pretty well. I'm not really sure what it looks like, you'd have to ask the people behind me.

Oh my...this seems to have gotten pretty dim pretty quickly.

Uh...let me convey a story to illustrate "why clipless pedals"...

It's Superweek 2008. I show up for a double in Bensenville. Hadn't raced since that spring so I was nervous and out of "pre-race" practice. I drive about 1 hour in Chicago morning rush traffic to get to the venue. I jump out because I am running late - forgetting that Superweek never runs on time - and go to clip in only to discover that I was wearing my mtb shoes. Same exact upper as my road shoes - just different soles/cleats.

I debated my options. I could try to get home and back - losing 2 hours (even superweek usually isn't that late), I could race in my flat soled shoes, or I could try to race with the mtb shoes. I played around and was able to sort of lock a part of my cleat against the pedal so I decided to give the mtb shoes a shot.

Every race a crit? Ever tried coming out of a corner without having a secure pedal connection? After the 4th corner where my foot came flying off the pedal so violently as I PULLED UP on the pedals that I found myself swerving and decided I had become a safety risk - I pulled out of the race.

If you ride a bike for more than 2 hours a year (statistical finding....from the institute for made up statistics) then you need to ride with clipless pedals. If you don't know why....well then you're doing it wrong. If you can't figure them out....well...then you're doing it wrong. Make sure you know what you're doing, practice in a field if you have to in order to get the hang of them. If they still don't juve with you then determine if other pedal types would work better. If that doesn't work....try role playing gaming. I hear D&D is making a comeback.

I wouldn't say 20% at least for general riding. Cruising around on the flats I would be surprised if it made much if any difference. But when the road points up, the steeper it gets the more important it is to be able to pull up. I was doing 3x12 low-cadence strength endurance intervals (seated climbing) today and the only way to muscle the cranks around is to apply the force around the entire stroke.

Also it's very useful having a power meter because I can actually see and quantify the forces involved. For example when starting from a dead stop, the torques involved are greater than my body weight, which means that I am getting contribution from the upstroke as well as the downstroke. For the seated climbing, 230W at 50rpm up a 10% grade worked out to about 480lb-in of torque, or about 70lbs of force. Seated, so no bodyweight contribution. The upstroke balances the downstroke to assist in power generation.

I'm glad you've climbed x many feet, truly a feat of strength mr costanza could be proud of! I kid... Anyways, i'm glad you changed your idea about power-generation coming from the up-stroke... really though that isn't coming exclusivly from your hamstrings, since the hamstring only moves the foot backwards towards the glutes like lifting your foot off the ground when running. On a bicycle though, the hamstring motion is not part of the platform pedal's dead-zone. The dead-zone occurs simultaneously when raising your quad up and using your hip flexor and abdomen like a runner lifting their quad from perpendicular to parallel(just like you do in a roman chair) with the ground after raising their foot up...

So yes, hamstring for sweeping back but, not pulling up and clipless pedals help to keep the foot planted at low rpm as another posted says.