Enduro/AM - The Weight Game

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Enduro/AM - The Weight Game
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Posted: Nov 18, 2019 at 15:42 Quote
crs-one wrote:
badbadleroybrown wrote:
Their statement should've been limited to "we sent a prototype part by mistake and it broke. While regrettable, this doesn't reflect the quality of the production part you'll receive."

I realllllllly have to wonder about this. They just accidentally sent out a media bike with a lighter than production frame? If it hadn't broken y'all think they would have said anything, or just been happy with the obviously lower-than-production scale shot?
That's exactly my suspicion as well... try to sneak by the lighter setup and then play full blame game once it blows up on them. Be curious to see how much another 1/4lb of weight in the swingarm would've affected the generally positive review as well. That's a pretty significant difference in unsprung weight.

Posted: Nov 18, 2019 at 17:02 Quote
badbadleroybrown wrote:
But they went full psycho. Honestly, the extent of their counterattack makes me question their quality a lot more than a broken swingarm.

That's Leo for you. His hostile commenting on Vorsprung's geometry video is another example.


badbadleroybrown wrote:
crs-one wrote:
I realllllllly have to wonder about this. They just accidentally sent out a media bike with a lighter than production frame? If it hadn't broken y'all think they would have said anything, or just been happy with the obviously lower-than-production scale shot?

That's exactly my suspicion as well... try to sneak by the lighter setup and then play full blame game once it blows up on them. Be curious to see how much another 1/4lb of weight in the swingarm would've affected the generally positive review as well. That's a pretty significant difference in unsprung weight.

Agreed, and it all paints a picture of someone who's aggressive and/or not entirely honest in the marketing. For example, I've heard from the Asian side that his "carbon is bad" and #oceanfill marketing campaign was simply because he ran out of money trying to purchase the molds for carbon frames, then created a very clever story to explain why he opted to use a heavier, more expensive, and - possibly - less reliable design and manufacturing process.

To be fair, I heard this through a trading agent, not directly from the factory he was working with, so consider it just tawdry gossip.


Leo seems to have acknowledged the personality issue in his comment in the review of the Stamina:

bigquotesI have sent an apology to Pinkbike for the drama. I am glad that they did not go for the click-baiting and therefore proved me wrong. I understand people who think I'm some half-assed guy because the only part they usually see from me is the opinions I have. I know that it creates a very opinionated image. I don't share my personal life on social media a lot, because... it's personal. During my MTB career, I have proved many people wrong (Except @WAKIdesigns, because he never seems to be wrong), and I know that it's not always pleasant to be proved wrong. In this case, I am truly happy to be the idiot that shouted the wolf.

Pole grows as a company all the time and soon, there will be someone else doing the press releases and forum talk. You will get something that does not show my personality any longer. There are a lot more people involved in the company already and I am handing over my responsibilities to others. When we started the company, I was doing pretty much everything that was about bike engineering, website UX design, marketing, communication or negotiation with suppliers. I have never been the CEO because I don't want to be handling the everyday stuff. My passion is in company strategy, engineering, and product development. We have finally found a very capable growth hacker who will take over soon the marketing activities and communication that I have been responsible for since the start. I will be available on our Facebook forum for our customers in the future for technical advice.

I would like to ask what people would like to know about Pole? For us, it's not very easy to realize what we are not telling outside that people would like to know.

-Leo

So, did he really learn a lesson? Was he forced out by investors who couldn't abide the unnecessary drama? Are we in an abusive relationship with Leo where he hits us, then tells us "I'm sorry, baby, I promise it will never happen again..."? Who knows! I don't like the guy, but I like the industry more for his presence.

Posted: Nov 18, 2019 at 18:43 Quote
But seriously, an XC rear triangle for a 140 bike with a 64 degree headtube angle? What kind of XC bike weighs eight pounds and has that kind of geo? Sounds like a crock of shit. It might have a been a proto swing arm, but...

Posted: Nov 18, 2019 at 18:47 Quote
Circe wrote:
But seriously, an XC rear triangle for a 140 bike with a 64 degree headtube angle? What kind of XC bike weighs eight pounds and has that kind of geo? Sounds like a crock of shit. It might have a been a proto swing arm, but...


Posted: Nov 18, 2019 at 21:09 Quote
gnarnaimo wrote:
skerby wrote:
I liked small rings back in 11spd days. I started at 32, went all the way down to 28 and climbed a lot better. Maybe not faster, but I could keep up with my buddies using less effort.

32/50 on the 12 speed is pretty low for 27.5, I love it though. Absurdly steep climbs here, Olympic Peninsula.

Similar terrain where I live to you. I'de love to see some of the folks here claiming 30/50 (29er) is too low clean some of the local climbs with their 32/42 setups.

I love it when people who live where the longest climb is 5 minutes dis those who live in the pnw for having a small chainring.

High rpm's work people. Don't bother grinding impossible gears rather than learning to turn cranks properly.

Posted: Nov 18, 2019 at 21:17 Quote
What kind of manufacturing company allows prototype components to migrate into production? That's a major red flag and shouldn't be possible. Design and review components should always be CLEARLY labeled and segregated/confined to an isolated workspace. Imagine a snapped head tube during H2F. Not good. I'm not convinced it wasnt sent on purpose. Prototype's get marked up for future NDT if they are doing things the right way.

Posted: Nov 18, 2019 at 21:46 Quote
rahrider wrote:
gnarnaimo wrote:
skerby wrote:
I liked small rings back in 11spd days. I started at 32, went all the way down to 28 and climbed a lot better. Maybe not faster, but I could keep up with my buddies using less effort.

32/50 on the 12 speed is pretty low for 27.5, I love it though. Absurdly steep climbs here, Olympic Peninsula.

Similar terrain where I live to you. I'de love to see some of the folks here claiming 30/50 (29er) is too low clean some of the local climbs with their 32/42 setups.

I love it when people who live where the longest climb is 5 minutes dis those who live in the pnw for having a small chainring.

High rpm's work people. Don't bother grinding impossible gears rather than learning to turn cranks properly.

It's funny.. I was one of those hammerheads for a while (still am on the BMX track, running way taller gearing than most) but the ebike was the bike that broke me of that habit.. They work the best at 80-100rpm and that was what finally broke me and got me to start spinning more and more.

Posted: Nov 18, 2019 at 22:00 Quote
rahrider wrote:
I love it when people who live where the longest climb is 5 minutes dis those who live in the pnw for having a small chainring.

High rpm's work people. Don't bother grinding impossible gears rather than learning to turn cranks properly.
Actually, high RPM have proven to be less efficient for the overwhelming majority of riders. The huge majority of people hit their peak endurance power in the 70-90 RPM range. The Armstrong/Froome spin to win technique is detrimental for most riders.

Posted: Nov 18, 2019 at 22:04 Quote
MikeAzBS wrote:
What kind of manufacturing company allows prototype components to migrate into production? That's a major red flag and shouldn't be possible. Design and review components should always be CLEARLY labeled and segregated/confined to an isolated workspace. Imagine a snapped head tube during H2F. Not good. I'm not convinced it wasnt sent on purpose. Prototype's get marked up for future NDT if they are doing things the right way.

Yeah, I don't believe it, either. I insist on inspecting a bike myself before sending it out. Although it's not entirely fair to give extra QC to a test bike, relative to what a consumer would get, it's necessary when so much is at stake. I don't believe any company would send a bike to a major site without looking it over.

My guess is this was either a sneaky trick to save some weight or really bad QC due to poor marking and checking procedures.

Posted: Nov 18, 2019 at 22:15 Quote
badbadleroybrown wrote:
rahrider wrote:
I love it when people who live where the longest climb is 5 minutes dis those who live in the pnw for having a small chainring.

High rpm's work people. Don't bother grinding impossible gears rather than learning to turn cranks properly.
Actually, high RPM have proven to be less efficient for the overwhelming majority of riders. The huge majority of people hit their peak endurance power in the 70-90 RPM range. The Armstrong/Froome spin to win technique is detrimental for most riders.

Ongoing research continues to refine these conclusions.

The latest I've read is that efficiency, cadence, and power all rise together. i.e. Maximum efficiency is at very low cadence when power is low because the metabolic cost of moving your legs is a greater fraction of the total power requirement, and vice versa.

Efficiency isn't the whole story, though: instantaneous efficiency is great, but doesn't account for endurance. Taking it to extremes for the sake of example, you could pedal a stationary bike with zero resistance all day and you can tear your muscles on a single one-rep-max, even though the latter used less energy. Depending on the length of the effort, it may be advantageous to be less efficient at higher cadence if it does less damage to the muscle.

Other factors include the mass of the rider's legs and training of the neuromuscular systems. It's been found that a rider's self-selected cadence is usually their most efficient, even if it's not their most efficient possible cadence. Their "natural" cadence can be retrained over a long period - potentially years - and may, eventually, become more efficient, though it's difficult to test and control for other variables over such a long duration.

Posted: Nov 18, 2019 at 22:16 Quote
My best bet is they sent an early production bike with a rev one swing arm. They called it “XC” because you know....

Lots of arm chair engineers in the review making claims about poor rear swing arm design. RMR, do you have any thoughts on that aspect?

Posted: Nov 18, 2019 at 22:55 Quote
Circe wrote:
Lots of arm chair engineers in the review making claims about poor rear swing arm design. RMR, do you have any thoughts on that aspect?

I do. I really do.

Armchair engineers are just people speaking beyond their knowledge. I don't want to be guilty of the same thing, so I'll try to reign it in.

First, I love the idea of rapid iteration in bike design. That's one reason Pole is evolving so quickly. In just a few years they've gone from moderately wild geometry and ultra low anti-squat to fully wild geometry and average anti-squat.

Another benefit to rapid iteration is reduced need for simulation. It's not even worth doing FEA if the cycle of design-build-test-redesign is sufficiently quick and cheap. On the spectrum of iteration vs. simulation, my understanding is that Pole is very much on the iteration end - that's old information, though, and maybe they've increased their simulations. As an example, I recall a story along the lines of the first rear triangle on the first Machine lasting about five seconds as Leo hucked it straight out of the workshop and off the loading dock. Back to the CAD drawing board - and there's nothing wrong with that. I've seen so many flawed FEA simulations that I view the results with considerable skepticism.

With the disclaimers out of the way ...

Envision the Stamina at full bump (bottom-out). A large component of the force is squeezing the chainstay and seatstay together. And the brace doesn't look to be nicely aligned to resist the force. The brace isn't hollow, yet it's super thin: not the most efficient shape to resist buckling (photo below). Bucking resistance probably would've benefited enormously from an increase in dimension out of the plane: a rib, a fold, some corrugation - anything. Space is limited in that area, but surely they could've found a couple millimeters and it would've greatly increased the buckling resistance. Another option is to bridge the stays closer to the pivots, as is done on VPP, dw, Mestro, KS-Link, Zero, etc. This is difficult with Pole's manufacturing method, though, which I can only assume is why it wasn't done initially. Pole has recently addressed this.



Posted: Nov 18, 2019 at 23:08 Quote
R-M-R wrote:
Maximum efficiency is at very low cadence when power is low because the metabolic cost of moving your legs is a greater fraction of the total power requirement, and vice versa.
This is backwards... high power/low RPM uses comparatively less energy to move the legs and diverts a far greater portion of overall power produced into driving power through the cranks whereas low power/high RPM uses a comparatively greater portion of power into maintaining the motion of the legs. High speed pedaling negatively affects the oxygenation of leg muscles and speeds the accumulation of lactic acid within the muscle as well as coming with higher heart rates which more rapidly fatigue the individual and lead to an overall reduction of exercise efficiency.

It is true that people generally settle upon their natural comfortable cadence and that's roughly their optimum speed, and that that speed can be increased through training, but that really applies to a small variance within a narrow window. Speeds above 90rpm are really only beneficial to the select few physiological freaks that are built to be pros. The demands it puts upon the average person's physiology are just too extreme for the huge majority of riders. Most riders are better off riding at 200 watts and 80 rpm than they would be at 150 watts and 100 rpm.

Posted: Nov 18, 2019 at 23:11 Quote
R-M-R wrote:
Envision the Stamina at full bump (bottom-out). A large component of the force is squeezing the chainstay and seatstay together. And the brace doesn't look to be nicely aligned to resist the force. The brace isn't hollow, yet it's super thin: not the most efficient shape to resist buckling (photo below). Bucking resistance probably would've benefited enormously from an increase in dimension out of the plane: a rib, a fold, some corrugation - anything. Space is limited in that area, but surely they could've found a couple millimeters and it would've greatly increased the buckling resistance. Another option is to bridge the stays closer to the pivots, as is done on VPP, dw, Mestro, KS-Link, Zero, etc. This is difficult with Pole's manufacturing method, though, which I can only assume is why it wasn't done initially.

My first thought when I saw that was why not just add a little rib to it? They might have gotten away with less weight than the regular version but with much better buckling resistance than the "xc" ( Rolleyes ) swingarm. Maybe even better than the regular swingarm if space allows. I mean the buckled xc one looks like cardboard basically.


Out of curiosity, have you ridden a pole or looked at the kinematics? Some of their early models in particular had some odd kinematics ideas if I remember right. Any thoughts on those vs new ones?

Posted: Nov 18, 2019 at 23:30 Quote
badbadleroybrown wrote:
R-M-R wrote:
Maximum efficiency is at very low cadence when power is low because the metabolic cost of moving your legs is a greater fraction of the total power requirement, and vice versa.
This is backwards... high power/low RPM uses comparatively less energy to move the legs and diverts a far greater portion of overall power produced into driving power through the cranks whereas low power/high RPM uses a comparatively greater portion of power into maintaining the motion of the legs. High speed pedaling negatively affects the oxygenation of leg muscles and speeds the accumulation of lactic acid within the muscle as well as coming with higher heart rates which more rapidly fatigue the individual and lead to an overall reduction of exercise efficiency.

It is true that people generally settle upon their natural comfortable cadence and that's roughly their optimum speed, and that that speed can be increased through training, but that really applies to a small variance within a narrow window. Speeds above 90rpm are really only beneficial to the select few physiological freaks that are built to be pros. The demands it puts upon the average person's physiology are just too extreme for the huge majority of riders. Most riders are better off riding at 200 watts and 80 rpm than they would be at 150 watts and 100 rpm.

It's not backwards. Perhaps I could've written it more clearly.

Imagine a person seeks to put out low power - let's say 50 watts, for example. If that's the ideal output for a given scenario, then it's best to pedal slowly. This isn't the cadence at which the rider can produce maximum power, but the metabolic cost of simply turning their legs would be unnecessarily high at higher cadence, so it's best to spin slowly. As the rider desires to put out more power, the rider's optimal cadence will increase - to some limit, of course, which is determined by physiology and duration.

It's too general to say "most riders are better off riding at 200 watts and 80 rpm than they would be at 150 watts and 100 rpm". The statement is almost certainly true for an athlete that can easily sustain 200 W. If a rider struggles to maintain 200 W, such that it's essentially a threshold output, then 150 W at almost any reasonable cadence will be easier for that person. This illustrates the more subtle point that an athlete may be able to sustain a less efficient cadence for longer, which makes for a faster overall ride.

I've also read about the reduced blood flow at extreme cadence. It depends on the individual and the situation. Sprints always involve high cadence because that's the optimum for the situation. Similarly, soft-pedaling at the back of a pack in a headwind is most efficient at low cadence. For most people, a one-hour time trial will favour the sub-100 cadence you've described. It varies by rider, by power output, and by duration required.


 
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