Lightweight Frame Tubing and "Planing"

[jimoots]

The concept of planing is absurd; and anyone with any exprience pacing intervals to a power meter can poke holes through their testing methodology.

Sitting the same guy on a bike for five “all you got” efforts and holding that up as your proof... it’s lazy and misleading to the casual reader who might actually place weight behind what’s being read.

And I found myself wondering if the author actually understood the concept of power as I read through the article.

Simply put if there was a 15% increase in power waiting to be unlocked based upon bikes - it wouldn’t be a concept being floated on the backwaters of the internet and there would be serious pro team R&D going into it.

But there’s not, so there isn’t.

[rain dogs]

Some of the stuff I read in BQ... man. I appreciate his passion, but it's a total echo chamber.

Maybe it's too obvious to state but power doesn't come from a bicycle unless it's electric. Nor from flex, nor from bigger tires, nor from 'planing'

Power comes from the rider. If you put 200W into a bike, you put in 200W. From there it's loss. There is no "more power" or "free power" or "increases" that's all mumbo jumbo.

In theory, it could be "more/less loss" when it comes to actually moving you forward, but you put 200W in, you want as close to the 200W out. Simple. Jan will lead you to believe that you put 200W in, and X is lost into frame flex/heat (because thermodynamics exist) and then X+Y is coming back?!?!? It cannot be X+ anything because the universe would implode.

It's X-Y coming back. And I am willing to bet you the "Y coming back" is so immeasureably small that it is inconsequential, the same with all of his vibrating molcules theory in the rider. Make the choice for comfort, not "free power". Some miniscule truth may be there, but it's better to call that preference, because we're also dealing with such TINY numbers. 200W is a tiny amount of power. His 15% claims, which are laughable, would be 30W which is miniscule power, and if it is actually 1 or 2 W here or there.... that's inconsequential, especially for the "real world" riders of the world. But hey, like changing 4g bolts for 2g bolts, if this is your thing - free world.

Forest thru the trees and all that.

[marciero]

Originally Posted by rain dogs

Some of the stuff I read in BQ... man. I appreciate his passion, but it's a total echo chamber.

Maybe it's too obvious to state but power doesn't come from a bicycle unless it's electric. Nor from flex, nor from bigger tires, nor from 'planing'

This is a total misreading. Nowhere is this claim made.

Originally Posted by jimmy-moots

Simply put if there was a 15% increase in power waiting to be unlocked based upon bikes - it wouldn’t be a concept being floated on the backwaters of the internet and there would be serious pro team R&D going into it.

But there’s not, so there isn’t.

I'm so tired of this argument. The fact is that no one does this kind of R&D, with real riders. Why should they when everyone simply accepts the stiffer-is-better mantra? When companies need only mass produce bikes in three sizes in Asia and furnish them to pro teams to get them sold there is no incentive. Having based all their marketing for years and years on stiffer is better there would be a natural reluctance to even allow the possibility that "...um, it's not that simple..." That the women's time trial world champion could not even get a frame in her size from the sponsor speaks volumes about how interested companies are in optimizing frames for individual riders.

How long was it simply accepted that higher pressure tires were faster? After literally decades, you finally have tire companies doing their own testing and finding that, as BQ has been saying for 10 years, no, it is not that simple, and professionals are finally using 28+ tires in races like Paris Roubaix.

Many here are honed in on this 15% number, take it out of context, and apply to all riders in all situations. It is one test, and I doubt that number would hold up to further testing. But rather than just dismissing, calling BS, and crying absurd, it would be nice to actually cite some study or test, or even some anecdotal evidence. Even anecdotal would at least be something. When someone here relates their actual non-scientific experience I usually give that at least some weight based on who it's coming from. But people just simply seem unwilling to even allow the possibility that for SOME riders in SOME riding conditions, a flexy frame MAY have a benefit over a stiff one. My own anecdotal would go something like this "on rides of 100 miles or more I am not slower, and possibly faster, and am also less fatigued, on my cheap Asian made skinny tube frame than I am on my "nicer" other bikes."

There is a recent podcast, yes with Jan Heine, but also engineers from, I think Cannondale or Specialized, finally allowing that stiffer may not always be better.

[rain dogs]

Originally Posted by marciero

This is a total misreading. Nowhere is this claim made.

It's made in numerous articles he writes about planing and the like: "We know that riders put out up to 15% more power on bikes with optimized flex characteristics."

BS. Riders don't 'put out' 15% more power because they are on a flexy bike. Or maybe they do because they ride harder during that part of the test, and ride casually during the other parts. A rider will put out X power, and the bike is moving at speed because of X Power minus losses. And for a test to be meaningful a rider should put out the exact SAME power, not '15% more' or 15% less.

If Jan wants to say: The power recorded at the wheel was 15% greater on the flexy bike than the power recorded at the wheel on the stiff bike.... fine (but unlikely). But even if that's what his small qty of data shows it is totally meaningless unless we know the power the rider was actually producing was exactly the same (and recorded numerous times for a realiable sample size under controlled conditions)

I can "put out 15% more power on a Wal-mart Huffy" than I can on a specialized Venge if I want to and decide to pedal wth variable power. I can quite easily ride a Venge at 150W and a Huffy at 173W. But that doesn't mean I should ride a Huffy if I want to go faster, further or have higher performance.

He repeatedly makes these types of conclusions. If you want to put out more power, ride a flexy bike! As if the flexy bike somehow enables you to overcome your physical limits and magically 'put out' more power! Sounds easy... why train?

And for what it's worth, and I said it above, choose the flexier bike if you wish. Choose if for comfort, choose it for a nice ride. Choose it because, maybe you will in fact see the tiniest less loss of power into the frame (1 or 2W) due to a myriad of dynamics. But don't choose it because you believe you're suddenly going to increase your FTP by 15%, or start 'putting out' 15% more power.

[etu]

Originally Posted by marciero

There is a recent podcast, yes with Jan Heine, but also engineers from, I think Cannondale or Specialized, finally allowing that stiffer may not always be better.

It's interesting how heated the debate gets when it involves Jan, almost like Grant Petersen, eh? I think no matter where you stand on the planing argument, it's hard not to admit he is probably top one or two most influential individuals for us recreational cyclists. Who has been leading advocate for larger tires and more flexible frames that are now so accepted as norm.
I am actually very grateful for his contribution to the sport in general and I feel that he has helped me with real, genuine improvement in my riding experience. From this perspective, I am much more inclined to give Jan the benefit of the doubt if there is a point that he makes that doesn't make sense to me.
Having read most of what he wrote frame flex and having subsequently ridden a fair number of miles on flexible frames, I didn't interpret his message to mean that a flexible bike will give you more power. No, I think he challenges you to consider that a bike with flex characteristics that match your pedaling style better might motivate you to push, harder and therefore go faster. The idea of bike and rider being a synergist whole is pretty cool IMO. This idea does not seem alien to custom builders, e.g. Dave Kirk and Carl Strong. Jan just has done a great job publicizing it and showing us the possibilities.

[marciero]

Originally Posted by rain dogs

It's made in numerous articles he writes about planing and the like: "We know that riders put out up to 15% more power on bikes with optimized flex characteristics."

No BQ claims ever violated the second law of thermodynamics, which is what you suggested. "Jan will lead you to believe that you put 200W in, and X is lost into frame flex/heat (because thermodynamics exist) and then X+Y is coming back? where Y>0.

Originally Posted by rain dogs

BS. Riders don't 'put out' 15% more power because they are on a flexy bike. Or maybe they do because they ride harder during that part of the test, and ride casually during the other parts. A rider will put out X power, and the bike is moving at speed because of X Power minus losses. And for a test to be meaningful a rider should put out the exact SAME power, not '15% more' or 15% less.

If Jan wants to say: The power recorded at the wheel was 15% greater on the flexy bike than the power recorded at the wheel on the stiff bike.... fine (but unlikely).

A rider will produce more power if they are less fatigued, or more efficient. But you've raised, and perhaps conflated, two separate questions-whether there is energy that is stored in the frame and returned to the rear wheel with a flexy frame, and whether the rider is able to produce more power with the same effort and level of fatigue. To test the latter, and in particular whether it depends on frame/rider dynamics, you would need a test of average power over some duration- it makes no sense to have the the rider produce the SAME power, unless you wanted to ask them afterward if they were more or less fatigued, which would be okay, though more subjective.

Many of us have worked to reduce inefficiencies in our pedaling motion. Is it so much of a stretch to entertain the notion that the frame itself might be part of that equation?

[El Chaba]

What makes a bike great is *balance*, and it is exactly what is lost on many (most) modern big box bikes. They can measure stiffness and add more, measure weight and reduce it....make it steer more quickly, etc...The talent and art comes in finding the balance point for any given parameter....

[adampaiva]

I don't know about other BQ readers and fellow owners of flexy skinny tubes planing bikes, but I am smart enough to take any and every thing Jan says with a grain of salt. And tbh I really don't care if I have 15% more power or if I am losing 15% because I just really do enjoy the ride of this bike more than my other bikes. And the sort of rides he does stories on are the same sort that I like to do. And I haven't found another cycling magazine to read that I like and its nice to still nerd on bikes but get off the internet.
I think we've digressed. What was the original question.

[weisan]

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[FlashUNC]

Aging MAMILs have more to do with the self-justification of searching out wider tires and less stiff frames -- and an industry looking for a marketing veneer to cover for the realities of why that is -- than any arbitrary sense that more cushion and more flex are mo' betta.

[adampaiva]

hey I had to google that but at 33 I hope I'm not MA and should take offense I did just come back from French Fender Day and was about half the average age of attendance.

To the OP. Don't do it. You'll be slow and won't like your bike and your friends will make fun.

[geordanh]

His tests are absurd to me, and to draw conclusions from them is nuts. I'm not a smart guy about science and stuff but the problems with his 'tests' in his magazines seem so blatant to me.

There's no control variable! If you really wanted to test his theory, you'd keep either power or speed constant on bikes with identical vertical compliance because at the end of the day, what he's saying is that lateral loading of a flexible frame as a spring makes you pedal more efficiently. Modern carbon all rounder road bikes have largely solved the vertical compliance comfort issue relative to steel so we should eliminate that as a test factor.

If you keep speed up a particular climb constant, according to Jan, the springy bike should be able to maintain a certain speed at a lower power output at the crank, right?

If you keep power at the crank constant, the springy bike should be faster up the climb, right?

What am I missing here? Why would he keep both speed and power as variable in a test like this? Just seems insane to me and so obviously open to tester manipulation.

If his point is that power output at the end of a long day is greater because the flexy frame is more comfortable, leaving a rider more fresh, that seems to hard to test under repeatable conditions. I do believe it, however, modern, non-aero-first carbon road bikes are, in my experience, no less comfortable than old, flexy steel frames. This wasn't the case 10 years ago, but these designs have come a long way in vertical compliance. Yet, they are vastly superior laterally and respond incredibly out of the saddle under high power.

[etu]

Originally Posted by adampaiva

hey I had to google that but at 33 I hope I'm not MA and should take offense I did just come back from French Fender Day and was about half the average age of attendance.

To the OP. Don't do it. You'll be slow and won't like your bike and your friends will make fun.

I am MA and I'll vouch that dropping testosterone levels and receding hairlines lead to a 15% increase in intensity of devotion to wider tires and flexible frames!

[R3awak3n]

I don't have a lightweight tubed bike so can't comment on planning but I like Jan enough. I am with Adam, there is no other cycling magazine I like to read, BQ is great and always interesting even though I don't always buy the stuff Jan sells. Its cool though. The guy has introduced some of the best tires in the market right now and really pushed for 650b stuff which is all stuff I like. He has super cool bikes and features awesome bikes in the magazine.

Planing, maybe exists, maybe not but sometimes I feel good on the bike and everything seems in tune and turns out to be a great ride, sometimes it doesn't. Stiff is not always better but springy is not always better either. Every bike for a different occasion is how I see it.

[marciero]

Originally Posted by geordanh

What am I missing here?

You are conflating the two issues I mentioned.

...and speaking of carbon-it is too bad no one seems interested in testing different layups. If planing is a real phenomenon and people are not just imagining it or making it up, and if it is attributable to frame flex in certain places I would think it could be dialed in and isolated better with carbon.