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The Pinkbike Podcast: Episode 131 - PB Editor Seb Stott on Geometry, Lock-Outs, Fickle Brakes, & Physics in Bike Reviews

Jul 6, 2022
by Mike Levy  
Pinkbike Podcast
Art by Taj Mihelich


Pinkbike tech editor Seb Stott joined us last February and has since written many in-depth and technical product reviews, comparisons, and opinion articles that take a more scientific approach to testing than we're used to seeing. Episode 131 sees Seb sit down with me to talk about how his degree in experimental physics helps him understand what's actually happening, the challenges of being a tall mountain biker, how he reviews a bike, why you're better off with having too much travel rather than too little, lock-outs, gearboxes, the brakes and suspension he prefers using, and a whole bunch more.

The Importance of Handlebar Height & Why It's Often Overlooked
Does a Lockout Actually Make Climbing Faster?
Why Your Bike Might Have Less Travel Than Claimed
Why a Lower Shock Position Doesn't Make a Bike More Stable




THE PINKBIKE PODCAST // EPISODE 131 - PB EDITOR SEB STOTT ON GEOMETRY, LOCK-OUTS, BAD BRAKES, & PHYSICS IN BIKE REVIEWS
July 6th, 2022

Too much or too little suspension travel?


Featuring a rotating cast of the editorial team and other guests, the Pinkbike podcast is a weekly update on all the latest stories from around the world of mountain biking, as well as some frank discussion about tech, racing, and everything in between.

This podcast is sponsored by Yakima.

photo


Previous Pinkbike Podcasts
Episode 1 - Why Are Bikes So Expensive?
Episode 2 - Where the Hell is the Grim Donut?
Episode 3 - Pond Beaver Tech
Episode 4 - Why is Every Bike a Trail Bike?
Episode 5 - Can You Trust Bike Reviews?
Episode 6 - Over Biked Or Under Biked?
Episode 7 - Wild Project Bikes
Episode 8 - Do We Need an Even Larger Wheel Size?
Episode 9 - Why Are We Doing a Cross-Country Field Test?
Episode 10 - Getting Nerdy About Bike Setup
Episode 11 - Are We Going Racing This Year?
Episode 12 - What's the Future of Bike Shops?
Episode 13 - Are Bikes Too Regular Now?
Episode 14 - What Bikes Would Pinkbike Editors Buy?
Episode 15 - What's Holding Mountain Biking Back?
Episode 16 - Who's Your Mountain Biking Hero?
Episode 17 - XC Field Test Insider
Episode 18 - Electronics on your Mountain Bike: Good or Bad?
Episode 19 - The Hardtail Episode
Episode 20 - MTB Conspiracy Theories
Episode 21 - Stuff We Were Wrong About
Episode 22 - Does Your Riding Style Match Your Personality?
Episode 23 - Grim Donut 2 is Live!
Episode 24 - Why Even Buy a DH Bike?
Episode 25 - Fall Field Test Preview
Episode 26 - The Three Most Important Mountain Bikes
Episode 27 - The World Champs Special
Episode 28 - All About Women's Bikes
Episode 29 - Freeride or Die
Episode 30 - Would You Rather?
Episode 31 - Wet Weather Riding Tips & Tricks
Episode 32 - What Needs to Change in the Bike Industry?
Episode 33 - Behind the Scenes at Pinkbike Academy
Episode 34 - Grilling Levy About Field Test Trail Bikes (and His Bonspiel)
Episode 35 - Story Time - Stranger Than Fiction
Episode 36 - Grilling Kazimer about Field Test Enduro Bikes
Episode 37 - The 2020 Privateer Season with Ben Cathro
Episode 38 - Editors Defend Their 2020 Best-Of Picks
Episode 39 - Predicting the Future of Mountain Biking
Episode 40 - The Pinkbike Awards!
Episode 41 - Racing Rumours and Team Changes
Episode 42 - Mountain Biking's Guilty Pleasures
Episode 43 - Dangerholm's Wildest Custom Mountain Bikes
Episode 44 - Mountain Bike Suspension Decoded
Episode 45 - What Makes a Good Riding Buddy
Episode 46 - The RockShox Zeb vs Fox 38 Deep Dive
Episode 47 - High Pivot Bikes: The Good, The Bad, and The Why?
Episode 48 - Rides That Went Horribly Wrong... & Why That Made Them So Good
Episode 49 - What's the Best DH Bike?
Episode 50 - Are Bikes Actually Getting Less Expensive? (Value Bike Field Test Preview)
Episode 51 - Should MTB Media Post Spy Shots?
Episode 52 - Our Most Embarrassing MTB Moments
Episode 53 - Should Climbers Still Have the Right of Way?
Episode 54 - Best and Worst MTB Product Marketing
Episode 55 - Big Dumb Rides & Staying Motivated
Episode 56 - What Were the Most Important Inventions in Mountain Biking?
Episode 57 - What Were the Best (and Worst) Trends in Mountain Biking?
Episode 58 - Debunking Mountain Biking's Biggest Myths
Episode 59 - Value Bike Field Trip Surprises & Spoilers
Episode 60 - What Kind of Mountain Biker Do You Want to Be?
Episode 61 - Athlete Pay, Lycra, Equality and More from the State of the Sport Survey
Episode 62 - Editor Preferences and Why They Matter
Episode 63 - Our Best (And Worst) Bike Buying Advice
Episode 64 - Who's On Your MTB Mount Rushmore?
Episode 65 - The Hardtail Episode
Episode 66 - The Best and Worst of Repairing Bikes
Episode 67 - The Story of Mountain Biking's Most Interesting Man: Richard Cunningham
Episode 68 - Who Are Mountain Biking's Unsung Heroes?
Episode 69 - The Good, Bad, and Strange Bikes We've Owned - Part 1
Episode 70 - The Good, Bad, and Strange Bikes We've Owned - Part 2
Episode 71 - The Story of Mountain Biking's Most Interesting Man: Richard Cunningham - A Pinkbike Podcast Special, Part 2
Episode 72 - Hey Outers!
Episode 73 - The Details That Matter... and Some That Shouldn't
Episode 74 - The Best Trails We've Ridden and What Makes Them So Special
Episode 75 - Things MTB Brands Waste Money On
Episode 76 - MTB Originals and Copycats
Episode 77 - Interview with Outside CEO, Robin Thurston
Episode 78 - Modern Geometry Explained
Episode 79 - What's the Future of eMTBs?
Episode 80 - The Best Vehicles for Mountain Bikers
Episode 81 - You've Got Questions, We've (Maybe) Got Answers
Episode 82 - Behind the Scenes at Field Test
Episode 83 - Does Carbon Fiber Belong On Your Mountain Bike?
Episode 84 - Explaining RockShox's Computer Controlled Suspension
Episode 85 - Is the Red Bull Rampage Too Slopestyle?
Episode 86 - Greg Minnaar on the Honda DH Bike, World Cup Racing, and Staying Fast Forever
Episode 87 - How to Love Riding When it's Cold and Wet
Episode 88 - Mountain Biking on a Budget
Episode 89 - The Derailleur Pickle
Episode 90 - Is Supre the Future of Trouble-Free Drivetrains? (with Cedric Eveleigh of Lal Bikes)
Episode 91 - Riding Every Double Black in the Whistler Bike Park with Christina Chappetta
Episode 92 - Does Bike Weight Really Matter?
Episode 93 - Staying Motivated and Overcoming Burnout
Episode 94 - PBA Contestant Tori Wood on Her First Race and Finding the Right Mindset
Episode 95 - Field Test Down-Country Bike Debrief
Episode 96 - PBA Contestant Israel Carrillo on Riding in Mexico and Why It's Not Always About Speed
Episode 97 - Can We Predict the Future of Mountain Biking?
Episode 98 - Field Test Trail Bike Debrief
Episode 99 - New Year, New You?
Episode 100 - Q&A with the PB Editors
Episode 101 - MTB Tradeshows Explained
Episode 102 - Should MTB Media Be Going to Press Camps?
Episode 103 - Secrets from the World Cup Pits with Henry Quinney
Episode 104 - Lachlan Morton on How to be a Happy Bike Racer and the World's Longest Climb
Episode 105 - The 3 Bike Budget Challenge
Episode 106 - What's Your Ideal Ride Look Like?
Episode 107 - How (And Why) Did You Start Mountain Biking?
Episode 108 - Behind the Scenes at the Value Bike Field Test
Episode 109 - Berm Peak's Seth Alvo on Making Videos 24/7, Soul Rides, and Building a Bike Park
Episode 110 - Trying (and Failing) to Reinvent the Mountain Bike
Episode 111 - The Pinkbike Racing Podcast: Episode #1 - It's All Downhill From Here
Episode 112 - The Pinkbike Racing Podcast: Episode #2 - The Lourdes World Cup Post-Race Wrap-Up
Episode 113 - PB Editors Answer Your Questions (again)
Episode 114 - The Placebo Effect and Your New Mountain Bike
Episode 115 - We Are One's CEO Talks Future DH Bike, E-Bikes, & Domestic Manufacturing
Episode 116 - New Bikes and Gear from Sea Otter
Episode 117 - Mountain Biking's Worst (or Best) Cliché Crimes
Episode 118 - Music and Mountain Biking
Episode 119 - Road Trips Gone Horribly Wrong
Episode 120 - Gee Atherton on Titanium Additive Manufacturing, Million Dollar Machines, and 3 New Bikes
Episode 121 - How To Film Rampage & Field Tests with the PB Team
Episode 122 - Do Social Media & Mountain Biking Go Together?
Episode 123 - The Pinkbike Racing Podcast: Episode #3 - Fort William World Cup Wrap-Up
Episode 124 - Bike Parks or E-Bikes?
Episode 125 - Nino Schurter's Mechanic on Prepping Race Bikes & His Favorite Tools
Episode 126 - "One More Run" and Other MTB Superstitions
Episode 127 - The Pinkbike Racing Podcast: Episode #4 - Leogang World Cup Wrap-Up
Episode 128 - Summer Solstice Adventures
Episode 129 - Are There Too Many MTB Videos? Interview w/ IFHT's Jason Lucas
Episode 130 - Aaron Gwin on High-Pivot DH Bikes, Chasing the Money, & Riding with Eli Tomac

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92 Comments
  • 27 0
 That was one of the coolest episodes yet!

Oh… seems i ride two sizes smaller frame than “norm”.
Fkit - i can’t ride for sht anyways.
  • 27 0
 WHERE IS THE GRIM DONUT, LEVY
  • 5 1
 This is literally all we care about.
  • 23 0
 In my garage
  • 3 0
 @mikelevy: what's got the longer wheel base... The 'nut or your mini?
  • 2 0
 @mikelevy: get it on the trail
  • 28 1
 Yessss Looking forward to this, love Seb's Nerding out articles.
  • 18 0
 Regarding lockouts - the question for me is solely is it less effort/am I less tired at the top, not is it faster.

I appreciate the 2 are related in terms of Watts required, but not sure how it works in the real world. I don't care if a climb takes Mt 60 or 120 seconds longer, I do care if I can get to the top feeling less flogged.
  • 5 3
 Can’t you just put in less effort if you want to be less tired?
  • 4 0
 @steddy: no. If a lockout limits power surges, reducing your nominal power, while average watts stay the same, you will get to the top having done the same amount of work while feeling considerably less bagged
  • 3 0
 Work done against gravity it always the same. In a perfect physical system (flat inclined plane, no friction) you'll expend the same amount of energy no matter how fast you do it.
The trouble is we don't live in a perfect physical world, so the lockout choice is about optimising energy lost in dampers vs energy lost due to losing traction.
Hence why it usually makes some sense to use a lockout on a fire road/tarmac to avoid losses in suspension, but maybe not on a tech/rough climb you want to prioritise not losing traction and momentum.
  • 1 0
 I always leave my suspension open as never have any climbs that are so smooth to justify locking it out.
  • 12 0
 As an OCD PB pod fan, I have to listen to each casts about 3-4 times, but I have to listen to casts Stott is featured in many more times. The dude is unreal and I love the rational science / math approach to it. At the core its all about how biking feels, but guiding that is solid facts & physics, etc. The man is a major asset so don't effing burn the guy PB.
  • 11 0
 Question for the PinkPod; Why are the big tire companies not making tire inserts themselves? Either special tires with “built-in” inserts, or they could just go crazy with marketing jargon about how their tire and insert are specific for each other with all sorts of beautiful synergies.

Procore might be an exception, but it’s weird and who uses that anyway?
  • 5 0
 This is an excellent question for the next podcast.
  • 2 0
 Could it be that they wouldn't want to admit their tyres aren't tough enough for use without an insert?
  • 2 0
 That's a good question and I would think it's mostly a result of specialization. The big tire companies (Maxxis, Kenda, Schwalbe, etc.) usually just make tires and that's about it, aside from a few off-the-shelf branded accessories. And inserts are a whole different manufacturing process and competency area.

Also, it seems to me like most of the insert companies are pretty small affairs, which makes me think it is a fairly specialized process and maybe there isn't a ton of money in it anyway (unlike tires, which everyone needs, while only a relatively small fraction of mountain bikers are using inserts). Maybe it is just not worth it for them. Like, yeah you could contract out an insert and put some marketing hype behind it for a small amount of consumers, but that might not work well in the end. And investing in a whole new product/manufacturing line might not make sense.
  • 1 0
 Vittoria makes the Airliner is the only one I can think of.
  • 12 0
 Might as well do a humbled episode with Jesse Melamed @mikelevy
  • 11 0
 Pretty short video tbh
  • 8 0
 Been running Shimano drivetrain for ages and then recently went back to SRAM on a new bike. Agree with Seb, the lock on the rear-mech is great, it’s simple and helps with removing the rear wheel. No clutch switch to forget, like Shimano. The rear mech doesn’t seem to wear out as quickly for me as the Shimano.

I’ve heard SRAM shifter/mech, with Shimano cassette and chain works well, getting some benefits from both systems.
  • 5 0
 I am a life-long Shimano apologist and fanboy.

I am currently running an XT 12s cassette and chain with a GX Lunar shifter/derailleur combo. I hated full GX but am in love with the SRAmano kit. I was not very happy with the life of my XT 12s derailleur and shifter combo or the lever effort despite “improvements”.
  • 3 0
 @mrpfp:

Stoked to hear the SRAmano works so good. Been thinking of doing the same once my sram cassette/chain need replacing. I love the positive shifter feel of sram, but add to that the hyperglide tech of shimano. Boom perfect.

I also have to say that I think sram cassettes are grossly overpriced for what they are. A GX cassette is around $350cnd whereas a XT is only $280. And the XX1 cassette is almost $200 more than the XTR. I have a hard time understanding what it is about the material choices and manufacturing process that makes srams cassettes so much more.
  • 3 1
 I'm not qualified to speak for recent drivetrains but all my bikes (4 with my son's) are on 10sp Shimano running beautiful and lasting well.
Saint or xtr shifter (microshif thumb on HT)
Zee derailleur (also 11sp xt but clutch lever brakes, easy and cheap to replace)
Xt chain (sometimes KMC)
Xt with 42 expander or cs4000 cassette
Spend extra dough on wheels and suspension Wink
  • 7 0
 @brycepiwek: I ran a hybrid AXS setup for a while and it was all the pros of both high-end drivetrains, worked so well.

The XX1 casseroles are SO damn expensive, zero excuses. But I've seen in person how (most of it) is made from a single piece of metal and the process is super cool, especially compared to how XTR uses a more traditional spider with riveted cogs. But I also love how XTR uses three different materials (so Shimano) and it shifts better under high load. But the XX1 one is fancy and light haha
  • 2 0
 @brycepiwek: I also run a sramano setup and it’s been the best of both for me. Hyper glide plus is a beautiful thing, however the clutch on my 12s xt derailleur failed after a couple months (as was the case with many customers at the shop I wrench for) and the shifter felt significantly worse than all the 10 and 11s shimano shifters I’ve used in the past. I now have X01 shifter and derailleur on an xt cassette and chain and it has been flawless. I’m on my third season and fourth bike with this setup. It’s just too bad sram clutch’s are so weak.
  • 1 0
 My GX derailleur from 2019 is still going strong with no issues but I've read talk about clutch issues with the GX AXS derailleur, does anyone have any experience with this?
  • 3 0
 Double down shift is why I keep running Shimano. Once you are used to it you can't go back.
  • 2 0
 @kanasasa: You've basically described my set up on both of my bikes (and IMO the best drivetrain around).
10 Speed - because it's strong, light(ish) and cheap.
XT shifter - for double down shifts
Zee mech - because it's short
Shimano 4100 11-42 cassette.
XT chains (rotating 3 at the moment).
  • 1 0
 @fartymarty: I think it depends on the bike, On a DH bike i'm probably only going 1 gear at a time so single shift is ok, on an enduro bike double downshift is great, as I can be in the lowest gear for climbing and quickly need to shift down half the cassette to descend
  • 2 0
 @mrpfp: I am running a 12 speed SRAM shifter and Shimano derailleur. I love it. The SRAM shifting feel and a clutch that works. The shifting performance is excellent. All the eagle derailleurs I’ve owned had their clutches wear out quickly and fortunately for me, my SLX derailleur has been flawless. My eagle cassettes have been super long-lasting if you are on top of chain replacement. Once my SRAM cassette finally wears out I will replace them with Shimano due to cost: SRAM is overpriced for what you get.
  • 1 0
 @melonhead1145: I'm on a trail bike but get your point about a DH bike
  • 5 0
 @seb-stott

This question has been on my mind for some time.

You’ve got two bikes with the same wheelbase and chainstay length, but achieve the same front center in slightly different ways.

Privateer 141 has a longer reach but steeper head tube angle (465 and 64.5 respectively) vs

Transition Sentinel which has a shorter reach but slacker head angle (450 and 63.6)

Which would be easier to weight the front tire?

I currently own the 141 and it really comes alive in the steeps but is a bit more of a struggle to wrangle on flatter terrain. I’m curious if a Sentinel would be better balanced due to the shorter reach but technically the front center still would be about the same. Would love to get your thoughts.
  • 2 0
 I suppose one difference would be that the front centre would shrink more through the travel with the steeper head angle, but really the difference in weight distribution is pretty similar. The steering feel will be different though.
  • 5 0
 Looking forward to the discussed experiment with long travel + two sets of tires. After a few years of swapping bikes this is where I've landed and think it works really well for where/how I ride.
  • 4 0
 "In Theory There Is No Difference Between Theory and Practice, While In Practice There Is." All these tiny 1% gains by lockouts, lighter bikes, ... may sound like nothing but I can clearly feel each of them in my legs and they add up. But even if I like lighter bikes I very much appreciate Seb's perspectives, thoughts and in depth approach. Looking forward to your next articles.
  • 1 0
 @futureearth Ha! That's my favorite quote!
  • 2 0
 I'm interested on Seb's opinion on pedal kickback not being a real problem at high speeds... I understand his argument for why that is, but I feel like real-world experience says otherwise, e.g. lots of pros seem to swear by the O-chain device and say they can feel the difference it makes. Any further thoughts on that Seb?
  • 2 0
 Also if you're braking or pedaling a higher anti squat number can feel quite harsh. The full coasting over bumps is probably a less common scenario than you might think.
  • 4 0
 Lots of pros also swear by magic anti-vibration stickers. I think with Ochain there is a benefit in damping chain slap via the elastomers, which could be why we see some high-pivot bikes (with virtually no pedal kickback) also running them. Unless you're riding trials or technical climbs, there's no downside to Ochain so you may as well run it even if the benefit is small or psychological.

With locked-out braking combined with rapid suspension compression, PK can be an issue but that's an edge case; having a decent amount of anti-squat and a (slightly) more rearward axle path is an advantage all the time.
  • 1 0
 @seb-stott: I don't know, but with my trailbike when I go down some junky terrain and I need to brake to contol my speed, the suspension really feels harsh. But when I can let it run freely over the same junky terrain it absobs it much better!
I think it's because the wheel might slow down or stop when in the air between bumps. And then at impact it will produce pedal kick back and hinder the suspension to compress.
Couldn't this be the cause of the harshness I feel?
  • 1 0
 Or is it chunky terrain? ;-)
  • 2 0
 @WoS: Im a bit late with an answer but anyway:

When I read "Suspension feels harsh under braking" the first thing that comes to mind is Antirise. A high Figure in Antirise can make the Suspension feel a bit harsher under braking.

Also like you mentioned, when you fully block your rear wheel with your brake, Pedalkickback can not be prevented by the wheel rolling forward.
  • 2 0
 Really enjoyed this episode. WHY do our brakes suck so much? Anybody got a good answer? Can we have better brakes if we accept more weight? (I don't mean going from 2 to 4 piston, I mean a more consistent and reliable 4 piston than what currently exists, and no, Trickstuff doesn't really exist in the real world).

Modulation is more than just squishiness. Code RSC has great modulation and doesn't feel squishy, at least not in a negative sense - obviously the lever doesn't slam the pads into the rotor like Saint. Meanwhile Code R has a more squishy lever feel and somehow also makes it much harder not to skid.
  • 2 0
 Try Hope. Can't speak for the new T4V4, but my T3V4 have been flawless for years.
  • 3 0
 Thanks! I suppose the problem with MTB brakes is the high mechanical advantage required to get enough power with one-finger braking. Any air in the system, flex, or seal squeeze is multiplied at the lever by the overall leverage/hydraulic ratio, leading to more sponginess and bite point inconsistency. Maybe we need simpler two-pot callipers with bigger rotors, such as the non-series Shimano brakes we mentioned or Formula Cura.
  • 3 0
 @seb-stott: currently running the Cura two piston brakes on my enduro bike. Plenty power but more importantly, super consistent feel.
  • 2 0
 I suspect one of the reasons Hayes Dominions feel so perfect and consistent is that they're simply larger than Guides, etc.
  • 1 0
 @seb-stott: Seb, thanks for the reply. Always appreciate your reviews, which tend to address whatever I was wondering about a given product.

Curas look good... topping the list for next time I may need brakes. I like the idea of a simple powerful 2 pot and saving money vs. Hayes or Hope.
  • 2 0
 @seb-stott

I also hate the double upshift on XT. Everyone says get an XT shifter and lower group derailleur, it's the best for value and function. Turns out my full Zee setup on the HT works way better.

Is there a way to block the second upshift on XT? Or is an SLX shifter pretty much the only solution?
  • 2 0
 I don't know of a solution other than swapping to SLX. I remember a bike check ages ago in MBUK with Brian Lopes who downgraded to an SLX shifter on his 4X bike; now that I actually get to ride bikes with XT or XTR I can see why.
  • 5 0
 NOOOOOO - double shift is the best once you get used to it. I would never go back.
  • 2 0
 @fartymarty: try sprinting over roots and rocks in your race run and shift up online to accidentaly shift up two...not cool. Cool if it works for you.
  • 2 0
 @Muckal: I don't race but get your point.
  • 4 0
 The thought of two tires one bike is intriguing. Any thoughts on a tire field test or a tire efficiency test plus impossible climb?
  • 2 0
 A quick note about heavy riders in relation to Brakes and "Modulation":
1) All brakes have "modulation" when you weigh over 220lbs.
2) Adding huge rotors and fancy pads to shit brakes (cough-Guides-cough) can help "trail" brakes work well enough on mild trails but if you like to take your trail bike down long fast steep sections those "trail" brakes are going to make things real exciting when they completely check out half way down the hill.
3) I should probably lose weight.
  • 1 0
 If lockouts make a very small amount of difference in how efficient a bike pedals or climbs how at the same time are different suspension designs and travel ranges being considered as making large differences? if suspension vs no suspension is similar how are all suspension designs not considered extremely similar efficiency wise?
  • 3 0
 I think a lockout on an efficient system makes a fairly small difference, but that's not to say the difference between an efficient and less efficient bike (both open) is small. Also, as we discussed, there could be larger differences in the physiological effort that aren't captured by the power meter data. I'm not against using lockouts by any means, but I think you may as well have a generous amount of anti-squat regardless, in which case the advantage is diminished.
  • 1 0
 @seb-stott: I’ve got a bold unplugged. Lots of travel, lots of anti squat, double lockout with the dt swiss suspension. Really does feel like a big effort difference when using the lockouts.
  • 1 0
 @seb-stott: Enjoy the tech deep dives you do Seb.
Question: When a bike has very high Anti-Squat (i.e. 150%+) I assume that any rider/ bike weight over the rear wheel is attempting to be lifted up by your pedaling? Therefore very high AS is wasting energy, even if it feels crisp and tall?
Please advise.
  • 2 0
 @SunsPSD: Exactly, at least in theory.

100% anti-squat is a theoretical ideal where acceleration forces acting to compress the suspension are cancelled out by drivetrain forces trying to extend it, but in practice, the acceleration forces depend a lot on your centre of gravity location, which varies by rider, terrain, riding style, whether you're wearing a pack, if your water bottle is full...

In general, I think there is good reason to go a bit higher than "100%" because there are other forces at play (and maybe because I'm tall!) but if you go too far efficiency will start to decrease again.
  • 1 0
 Gonna have to disagree with Seb on the whole "run a longer travel bike with stiff settings". Maybe he over simplified it but it completely ignores how bikes will have different leverage ratios deeper into the travel or how you can tune the end stroke ramp-up on many shocks and forks. And again maybe he oversimplified for the podcast and I'd love to read his old article about it but I'm not of the opinion that my enduro bike will ride the same as my XC bike just because I run similar sag numbers.
  • 2 0
 For sure it's a simplification, but there's no reason you couldn't have the same wheel rate in the pedalling part of the travel on a long vs short travel bike.
  • 1 0
 Also shorter travel bikes tend to be shorter (slacker HA, shorter CS due to less travel). A long travel bike is still going to be long if you reduce the sag.
  • 1 0
 @seb-stott: Regarding tires making the bike, I agree. But would like to see test times between an AM & a XC rig, then install the XC drivetrain on the AM bike and see where it lands time wise.
I think about 70% of the speed difference is in the tires, about 15% in the other rotating weight, about 10% in the Kinematics & about 5% is in the total bike weight difference.
This review/ comparison can be done!
  • 1 0
 Back to pedal kickback: Has anyone considered that in pumping situations, if the chain is under tension, you’d get power fed into the rear wheel causing forward rotation? It would be a benefit. Search for the Radio Flyer Inchworm and you’ll see this idea in action.
  • 1 0
 Few questions for Seb, 1. In his opinion, what is the best bike out there right now from a physics standpoint? 2. Why don't enduro bikes focus more on anti-rise? It seems to me this would be more of the performance metric of interest for going downhill while braking and how the suspension works whereas anti-squat is more of an efficiency metric. 3. Speaking of anti-rise, it seems enduro bikes are either in two camps, either slightly above 100% or down near 45%, why is this and which one is "better"?
  • 1 0
 I actually just messaged @seb-stott about this, and then saw this podcast he's on, so apologies if it's addressed in the episode. I never hear q-factor discussed. As a tall rider (6'4" 192cm) it seems like I should have a wider stance than a shorter rider. Trying to figure out how to experiment with changing it, but it's pretty limited I've found.
  • 1 0
 YES, I remember having a Manitou fork on my old Canondale Gemini and lowering the fork made it feel like it was harder to pedal. Really strange and I thought I was the only one. … @mikelevy
  • 1 0
 Nope, I've heard a bunch of people say the same thing! No idea why, though.
  • 1 0
 @mikelevy: I could never figure it out either.
  • 1 0
 Same here!
  • 1 0
 @mikelevy: There is a new Zeb with travel that can be adjusted with a dial.
  • 1 0
 I remember Richard Cunningham trying to explain it.
  • 3 0
 I always find I'm breathing hardest when I'm climbing in the bottom gear. Therefore the bottom gear makes climbing harder. Wink
  • 2 0
 Can you just do a @seb-stott Segment as a regular part of most podcasts? The bloke would be in my top three bike thinkers/writers/testers/journalist ever.
  • 3 0
 Seb is a legend, so stoked to hear him talk nerdy!
  • 1 0
 @seb-stott - any relationship to subterranean bass / megadeep industrial sound tyrant Andy Stott? Longshot but - ya know, another form of mathematical genius
  • 1 0
 Anyone else notice Levy grabbed the “how are you, and where are you line from the David guy at Bikes and Big Ideas/Blister?
  • 1 0
 Not so much, it’s from Alan B Smith on Paranormal Now Wink
  • 1 0
 @brianpark : what did @mikelevy do this time to deserve that Yakima ad read? I could hear the eye rolling through my ear buds as he read those rhymes.
  • 1 0
 @mikelevy on less steep terrains what is your preferred reach for today's bike geometry?
  • 3 1
 Proposed topic for future podcasts - THE EUROPEAN BIKE PROJECT
  • 2 0
 As an engineering-nerd/data-geek, I'm looking forward to this one.
  • 1 0
 Why is over 100% (within reason) a good thing? How do you position the COG to calculate it?
  • 1 1
 The shock lock out thing was probably affected by design patents on suspension layouts. (FSR, seat tube intersect points)
  • 1 0
 Where in the living hell did the misnomer “leaver blade” come from??
  • 2 0
 Canada. They are leaver blades, not lev-er blades.
  • 1 0
 So glad ya'll are back!
  • 1 2
 Couldn’t finish this episode. I have never read an article by Seb that I agree with.
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