Seat Pads absorb power??

[Osiris]

https://cruzbike.com/pages/fastest-road-bike-guarantee

Not sure the details but it sounds like putting money to back up the claims.

But there's no mention in that guarantee about handlebar wagging; that's a separate claim entirely. I'm surprised Jim would even make such a guarantee, given the number of faster bents around. As much as I love my V20 as a general purpose bent, it's no match for either my M5 or M1 when it comes to outright speed.

I don't agree on the testing the same cruz waggling vs no waggling because in my mind, some waggling is necessary to prevent tire squirm.

But that isn't going to show what you want it to. For starters, which bents would you use in the comparison? Larry Oz was able to produce a ton more power on his S40 than his V20. He attributes that solely to the difference in seat angle, not to wagging/not wagging the handlebars. Similarly, he mentioned that he can't produce as much power on his Arrowhead as he can on his V20. I've also seen big differences in power output when comparing my RWD bents. So depending on which bents are used, you're going to get all sorts of different power measurements, but it will not have anything to do with handlebar wagging. And there is still the problem of dealing with the unfalsifiable objection that if the test you envision shows no positive result, it could simply be discounted as poor technique on the part of the test subject.

 

[ed72]

Let's imagine 50 bent riders with CA3 and V20 bents with the seat angles identical, setup and all components identical with the same power meter used per rider.

If we ran the experiment 5 times with the CA3 and 5 times with the V20 for each rider.

What if the 5 minute power from Bike 1 (all 50 riders) was 350 watts mean and 15 watts standard deviation and Bike 2 was 325 watts mean with a standard deviation of 15 watts. What conclusion would you reach? Obviously, more power is made on Bike 1 (a p-value could easily be calculated). Now, why is harder to disprove at that point. That is why I suggested looking at muscle perfusion and saturation levels as well and mentioned cross country skiers. Perhaps, V20 waggling vs no waggling would be a better design. Nothing can ever be proven but disproving is never a profit motivator in industry, so, verification rules in the real world. Not falsification. We aren't looking at Grand Unifed Field Theories, it is usually something more mundane and measurable w/o such far reaching consequences. Ya know.....is the tread wear better on the GP5000 over the GP4000 tires. yes. much better per my data. Does changing the heat treatment on a stent improve fatigue resistance, etc. There is a scientific or engineering basis that is rooted in making a better and/or cheaper product. It is never a philosophical perspective.

How many or any engineering DOE type protocols have you seen address fasifiability?

As many variables as possible are controlled. We can only accept or reject with certain confidence levels and lastly, should one falsification be sufficient to undo or nullify a theory. I don't know how many hundreds or thousands of protocols or studies that I have reviewed or approved (or rejected....LOL) over the decades, but one thing I know.....an adequate study wouldn't like this would not be cheap (even if done at a University) and even if it was conducted, the nail biters would want to tease the raw data to support their delusions. A no win situation. So, a better focus is on wins. Who wins more? V20. QED.

 

[Osiris]

Let's imagine 50 bent riders with CA3 and V20 bents with the seat angles identical, setup and all components identical with the same power meter used per rider.

If we ran the experiment 5 times with the CA3 and 5 times with the V20 for each rider.

What if the 5 minute power from Bike 1 (all 50 riders) was 350 watts mean and 15 watts standard deviation and Bike 2 was 325 watts mean with a standard deviation of 15 watts. What conclusion would you reach? Obviously, more power is made on Bike 1 (a p-value could easily be calculated).

I still don't understand why you'd construct the test that way if your purpose is to determine whether wagging the handlebars on a Cruzbike generates more power. Wouldn't just having every test subject ride the same Cruzbike be the better solution?

Perhaps, V20 waggling vs no waggling would be a better design. Nothing can ever be proven but disproving is never a profit motivator in industry, so, verification rules in the real world. Not falsification. We aren't looking at Grand Unifed Field Theories, it is usually something more mundane and measurable w/o such far reaching consequences. Ya know.....is the tread wear better on the GP5000 over the GP4000 tires. yes. much better per my data. Does changing the heat treatment on a stent improve fatigue resistance, etc. There is a scientific or engineering basis that is rooted in making a better and/or cheaper product. It is never a philosophical perspective.

How many or any engineering DOE type protocols have you seen address fasifiability?

Falsifying the actual performance claim can be done by just running enough tests to get consistent data. What is far more difficult is disproving the easily anticipated objection: "You didn't get more power because your technique was faulty".

So, a better focus is on wins. Who wins more? V20. QED.

Who wins more has a lot to do with who races more and who is doing the racing. Years ago Suzuki was winning virtually all the club races in this area. The reason wasn't because their motorcycles were better or faster, but because they simply made it a priority to have their brand over-represented at every race.

 

[Ross Jantz]

We've been over this before. I'm still waiting for a shred of credible evidence to substantiate that claim.

So you don't believe Cruzbike riders can add power with their upper body, but you do believe you can turn a purpose built track bike, however beautiful it may be for its intended purpose, into a viable road machine? Belief is an interestingly human construct bearing little relation to reality or evidence.

There is plenty of "credible" substantiating evidence - certainly more than has been provided for the claim that riders gain as much advantage pulling on the bars of a RWD recumbent (i.e., there is absolutely no evidence I know of for that). That isn't what you're looking for. You want incontrovertible, undeniable proof - a much higher standard than credibility. Bottom line - it is next to impossible to come up with a valid testing protocol for things deeply rooted in technique. Its also next to impossible to convince someone of the truth of something they have already decided is false.

Even anecdotal evidence IS credible when it is voluminous and consistent. Not proof, but credibility. Jim's experimental design may be flawed, but I haven't seen any better attempts to quantify the effect and even if flawed it provides at least some credible support if not actual proof.

There is a difference on an upright between "getting out of the saddle" and "dancing on the pedals." Most cyclists, I think, accept this. You can see it on the road when observing other cyclists and you can feel it on the bike - it just feels different when you get the timing/gearing/positioning just right. Is that difference testable? Does it show up on a power meter? I don't know and, frankly, I don't care. I can feel the difference on my S40 between 'waggling' the bars while pushing harder with my legs to compensate (feels like pounding the pedals while climbing on an upright) and getting the rhythm/amplitude/power of the boom movement just right - the bike either jumps ahead with a cadence increase at what feels like the same power or continues at the same speed and cadence at what feels like less power (just like getting it right on an upright).

When the equations said bumblebees couldn't fly but reality said they could, it wasn't the bumblebees that were wrong. I can climb as well or better than the upright riders I ride with of similar age and ability on a bike that weighs twice as much. I can climb faster on my Q or S than I can on my other (RWD) recumbent. There are no other FWD recumbents that even try to claim they are faster than CBs. The only major difference between my bike and these others is that it is a FWD-MBB recumbent. If its not the moving bottom bracket, then what is it? Its sure not an aero advantage at climbing speeds. If it is the moving bottom bracket, then the movement of that part must be the reason regardless of anyone's belief or doubt.

 

[Osiris]

So you don't believe Cruzbike riders can add power with their upper body, but you do believe you can turn a purpose built track bike, however beautiful it may be for its intended purpose, into a viable road machine?

When have I ever suggested that? I'm pretty sure I've said exactly the opposite.

Even anecdotal evidence IS credible when it is voluminous and consistent. Not proof, but credibility.

Perhaps you have a lower standard of proof than I do, or you're just happy to have your own beliefs confirmed by others. I don't consider unsupported claims to be evidence of anything other than what people believe they experienced.

There is a difference on an upright between "getting out of the saddle" and "dancing on the pedals." Most cyclists, I think, accept this. You can see it on the road when observing other cyclists and you can feel it on the bike - it just feels different when you get the timing/gearing/positioning just right. Is that difference testable? Does it show up on a power meter? I don't know and, frankly, I don't care.

And that perfectly illustrates the difference between you and me.

 

[billyk]

The rider's arms do provide extra power when more power is wanted, much like any other sprinter on any other bicycle.

I'm no expert, nor am I winning any races, but I do have well over 10k miles on my quests, after a decade of riding other bents. Long ago I was on a competitive rowing crew, and understand that motion, which has no seatback at all and the seat bottom slides freely: every bit of power is between pulling with your arms while bracing against the footrest.

I can cruise along no hands for miles, riding like a non-MBB bent, even climbing a fair hill. Then the power very clearly comes from pushing against the seatback.

But when I'm working the bike hard I'm sure I could do just as well with no seatback, like I did when I was rowing. It's a whole body motion; hands to feet. My upper back lifts off the seatback as my arms pull hard, and transfer that pull to a stronger pedal stroke. I don't need a power meter to tell me that I'm climbing that hill faster by doing it.

Otherwise why have an MBB @Osiris ? Cause you like a short chain?

 

[DavidCH]

I had a deluxe Ventisit pad but opted to take the liner out and see what that was like. Not bad now that i am lighter but i still think the rubber matt that i had was faster but warmer. I am going to change the tires to 28mm GP 5000 TL ... my best year for speed was 2016 so... time to radicalised my bike efforts.

 

[Osiris]

I don't need a power meter to tell me that I'm climbing that hill faster by doing it.

A woman I often ride with absolutely swears that she can climb hills faster by pulling back on the handlebars. I've tested the theory, and it certainly feels like I'm generating more power. One look at my power meter, however, reminds me that perception often has nothing to do with reality.

Otherwise why have an MBB @Osiris ? Cause you like a short chain?

There are several mechanical benefits to an MBB, but for me the greatest among them is that it completely eliminates the possibility of a heel strike when executing a tight turn. That's a serious problem on my other RWD bents, particularly the two racing recumbents. One other thing I happen to prefer about the MBB is that it makes the front end much less twitchy than my other bents are. The wide handlebars together with my legs act like a steering damper. I can pilot the V20 very aggressively through turns without worry that a small miscalculation in the amount of handlebar input will send me straight into a fence or curb. One thing that's true of Cruzbikes in particular is that you can change the height of the BB to whatever suits you best. All it involves is swapping out the chain stay for a shorter or longer one. An MBB also does away with the extremely long chain and the idler wheel(s) RWD recumbents require.