Classified HUB - How it Works and Efficiency claims: Part 1

[@global_nomad.]

great video - please don't cut these types of video down - they need a full explanation. Engineering Explained has a competitor!

[@PeakTorque]

Its a combination of technical breakdown and interest retention. Its very difficult

[@global_nomad.]

@@PeakTorque you're getting it right - but then i do 2hr university lectures....so youtube views might not be the same thing

[@AlanJames]

If you put chapters in then you can tell folk where to skip to if they want to avoid the more in depth bits. I'm not sure if that affects viewing figures though.

[@gregknipe8772]

@@AlanJames YES!!

[@ExplorinDoranRBrown]

@@AlanJamesit could reduce the view times if people can skip around easier, but it leads to a better experience and more people will watch his other videos and subscribe. Everyone gets what the want, skip the technical stuff if you want. But the better he explains the technical stuff , the less people will have or want to skip it

[@nathanphillips875]

I don’t normally like and comment on any KZbin videos, but this is ace. Perfect explanation with zero bullshit… keep up the good work 👍🏼

[@shannonparker7404]

Mate, seriously, thank you for the time and effort you have put into this.

[@ellipticalsoul]

Very good explanation of how it works, looking forward to seeing what your real world numbers are

[@parapunter]

In ten years of maintaining fishing reels I've developed a dislike/fear of roller clutch bearings. They're always the first thing to fail and reel manufacturers recognise this because they're usually backed up with a ratchet and pawl. They're very fussy about lubrication - too much they won't lock in reverse, too heavy they'll lock in the forward direction. As the lubricant migrates maintenance becomes tricky. Now I know sprag clutches are used reliably in automatic transmission, but I wonder whether Classified's application of them is closer to a fishing reel than a vehicle. Also, more generally, to continue the fishing reel analogy - every new fishing reel is reviewed as being super smooth and a joy to use. Of course it is - it's new. What really matters is how it performs after a couple of years heavy use and how maintainable it is.

[@PeakTorque]

Interesting comparison that. All i know is, the CTO and Inventor(s) background is in tier 1 automotive transmission design, so I'm pretty sure they've got it dialled. But you never know!

[@VEC7ORlt]

Jee, I wonder how does that Alfine 8 holds up for 4kkm I've ridden it for. Also silence is bliss.

[@badappel27]

@@PeakTorque could you still use the classified hub with 2x?

[@dogphlap6749]

Thank you for not dumbing down this video too much. A very impressive video for what appears to be an impressive hub planetary gear box. I'm surprised this is grease lubricated rather than oil but I've no doubt the folks at Classified know what they are doing. While waiting for Part 2 I'll do some background reading on this item. Shame this is only 1:1 and 1:0.7 but for some of us who might live in a flat place like Florida or the Netherlands that might be enough to allow us to ditch the derailleur completely and cycle with just those two ratios.

[@TheAsigmaOfNone]

Fantastic explaination of the hud! It really made sense after you talked though the patent drawing

[@sustainf]

Yes, excellent & well needed video. Consumers of cycling components, wheels, etc need more of this.

[@nstrug]

Fantastic video - and I have to say I'm really impressed with the whitepaper, clearly some serious engineers doing serious work at Classified. I'm very much looking forward to part 2.

[@PeakTorque]

Agreed.

[@Cyclingabout]

Very well explained, PT! 👏🏼 It'd be great if you could discuss the effect on cycling speed in any upcoming videos about the Classified hub. I suspect when you've factored in air and rolling resistance, any speed differences as a result of frictional losses could be virtually inconsequential to all but the top-level athletes.

[@PeakTorque]

As briefly mentioned the losses increase the faster you go, which in the reduction gear gase, is absolutely fine as you'd only use it for climbing where high torque and low speed have it most efficient.

[@azamwaugh]

Alee correct me if I’m misunderstanding, but I think he’s saying the following. Suppose you measure the classified hub’s real-world efficiency to be X% at Y mph. Would would be the delta in speed that a real rider would see if they instead used a DT Swiss hub with Z% efficiency.

[@futw3292]

What a great video!! I would really appreciate an in depth video into the mechanism that switches between a and no connection of the sun-wheel and wheel-carrier!

[@PeakTorque]

That is a very clever part. There are 3 or 4 possible solutions they could have gone with (in the patent) and i'm not sure which without taking it apart. The actuator is always actuated wirelessly by the induction coil set inside the thru axle, however,

[@MS-bw7yt]

I am very much looking forward to the real world testing. To be fair, I haven't looked into the white paper myself, but I am still surprised/very impressed by the 99% efficency claim. I am an engineer in the automotive industry myself and planetary gearing normally has a efficiency between 95 and 97%, maybe 98% when you are really good. But 99% although only 1-2% percentage points highter is a very big deal. Especially in the cycling industry where most companies are to stupid to make a round hole for a bearing ...

Painfully complicated solution to a simple thing that isn't really a problem. I love it!

[@cjohnson3836]

Overly simplistic lemming response to a product that addresses one of the biggest tradeoffs in mountain biking: modern linkage design vs gear range and gravel: gearing vs tire clearance.

[@veganpotterthevegan]

Rohloffs are outstanding and even more complicated with low drivetrain losses. I'd happily run one if you could shift it under load. This definitely simplifies things for the user. I just wouldn't want the drivetrain losses that are likely going to show up with these tests.

[@veganpotterthevegan]

​@cjohnson3836 not many people worry about gear range on mountain bikes anymore. Barely anyone worries about it on gravel bikes. My 1x gravel bike has a bigger range than my 2x road bike. The problem is the gaps in gearing which this certainly addresses

@@cjohnson3836 i use a 2x12 on my XC mtb, which gives all the range. I don't care about this product, simply the innovation and skillful engineering is what i love about it. Just like the internal gearbox systems, i don't want them yet, but great concepts that might turn out to be amazing in the future.

[@totallynotraging]

​@@cjohnson3836are classified going to be making spares and repairs for this in 5 years? More hyped up landfill junk for dentists with more money than sense.

[@paulround4691]

The sleave on the inner shaft for the one way needle bearing is possibly pressed but it's keyed at both ends...it's on the drawing!

[@RobertRobert-uc7fi]

Hambini is proud of you

[@williamstevenson2649]

Very good, very fair and very well explained for a 'lay' audience like me. I have no intention of buying a Classified because I'm not a racer and I'm very happy with 2x and avoided all the Ultegra/ DuraAce duff cranks. If I was a racer and had lots of money, I would be happy with the efficiency after your efforts, but I'd be waiting to see about the water ingress incident and concerned about the expense of them sending out this huge amount of bespoke scrap to every purchaser

[@fieldlab4]

Larger rings also mean worse chain angle which has the largest effect on chain efficiency.

[@davehause8571]

Really appreciate the science-based approach, no subjective opinions expressed. Thank you.

[@olbtube]

Excellent video! Thanks for the detailed explanation of the paper too, it's really worth having efficiency numbers at different gear ratios and sense check that with use cases, as well as adding chain tension into the discussion. I am also curious about how this system will behave over time, does it need servicing, can it be serviced by the average joe without loosing on tolerances, which bearings are going to fail (first), ride feel, etc...looking forward to part 2!

[@xaviermelendez2639]

Wow, kudos on the in-depth and well thought out review. Can't wait to see the next video installment!

[@oliversharp7383]

Great delivery on this one, nice nerdy deep dive!

[@Adonis-qj1nq]

Really good video, looking forward to part 2. This system could be very interesting if they integrated it with Shimano Di2 and didn’t require an extra button installed.

[@matthewbenger8355]

Shimamo isn't interested. See them more as a competitor. They are looking at making a groupset with TRP

[@Adonis-qj1nq]

@@matthewbenger8355 Well hopefully someone comes up with a third party hack, maybe using the Garmin D-fly programmable channels.

[@PeakTorque]

It can be spliced into di2....

[@timhall7771]

Very much looking forward to the next vid... spec'ing a new bike right now and the Classified system is an option I'm looking at...

[@thebikepackingadventurer]

Explained brilliantly and easy to follow with great detail. I’ve considered this hub for my gravel bike as love the 1x system for ease, but when bike packing on it with the weight, would be good to have a very easy climbing gear. This could be the one 🤷🏻‍♂️

[@PeakTorque]

Glad it was helpful!

[@zzhughesd]

Hello it’s Hambini Intro. Hadn’t picked up on that until now. Blond me.

[@chriswhite5665]

Excellent video. Not too long, and a good explanation. Looking forward to seeing your test results.

[@adambarlev8992]

Thanks for the video, I'm still with you

[@markhagen7777]

Thanks for taking this on and taking us seriously it’s great to be pressed to understanding reasonably sophisticated engineering , I certainly don’t have any particular background so you’re bringing at least me a long reasonably

[@PeakTorque]

Glad you enjoyed it!

[@matthewshaw3747]

To me it feels like the main barrier to this becoming the standard as part of top end group sets is scale (meaning cost) and integration. SRAM love to buy stuff so I wouldn’t be surprised if they bought this.

[@rosomak8244]

The main barrier to this becoming the standard will be the fact that it is not a new inefficient design principle, coupled with all the electric issues which still has been walled off with some trivial patents as usual, so it can be sold hugely overpriced to the dumb with too much money. Another "solution" looking for a problem, which is inventing thousands of additional problems in itself.

[@MaximeTrepreau]

Impressive job. Thanks. Can't wait for the next video.

[@zygmuntthecacaokakistocrat6589]

I'm just waiting for someone to repeatedly pressure wash this hub, then need a complete bearing set replacement when one or several of them seize. It's hard enough on a conventional hub . . . & looking at the cross-section can see at least 8 bearing races that might possibly get full of high-pressure soapy water.

[@moserroman2083]

this

[@andybarnard4575]

If the greatest hub loss is main bearing seal friction, Im glad Ive got a cup and cone hub from 1988 which has no bearing seal.

[@GiorgioCamozzi]

Thanks for taking into account the losses/gains through different chain forces! Can't wait to see the results!

[@TheGinger1]

Great video, looking forward to the next one. I'm interested in this for my next CX project. The idea of being able to kick into a steep bank and then drop the ratio to kick up it at full load sounds great.

[@PeakTorque]

One serious issue i have found is this - there is no feedback on what ratio you are in. It needs rocker/2 buttons. Ive often downshifted in at a real steep climb to often find i was already in the small gear, and then boom you grind to a halt. Really annoying.

[@natheirabu-dahab1446]

@@PeakTorque Classified claim you can shift under load. Can you not just hit the button again?

[@PeakTorque]

@@natheirabu-dahab1446 yes you can

[@emmabird9745]

Hi. The over-running clutch (needle bearings on ramps) is similar to those used on back pedal brakes. I took one out of a Shimano hub gear to use it as rim brakes. The torque reaction arm is similar, in-principle, to those used on hub brakes (drums not discs) but performs the function that flats on the axle against the drop-outs on conventional IHGs. In-principle the over-running clutch usrd here could be employed in multispeed IHGs for a useful improvement in efficiency. The Shlumf bottom bracket planetary gear gismo achieves the same 2by on a 1by advantage. The combination of IHG and derailieur is not new, indeed many Bromptons have 3x hubs with 7x derailieurs. One thing that puzzled me when I first saw this was the way they change the hub gear. Electronic, fine, so wireless too. Also fine. However, if you're a racer (and there are pros using this) how do they get on with punctures? Does the team car have dedicated wheels for each bike or can any bike pair with any wheel (involving a pairing process at the side of the road while the race goes on) or do all the bikes in the team pair with all the wheels, bringing with it the perils of ghost shifting when you're close or is it something else? I look forward to part 2.

[@raphindahouse]

the shifting pairs not to the wheel, but to the thru axle. so you can change wheels.

[@emmabird9745]

@@raphindahouse Hi, thanks, that makes sense a problem solved. So electrical contacts on the axle.

[@raphindahouse]

@@emmabird9745 the axle has the electronics and activates the shift via induction

[@emmabird9745]

@@raphindahouse Ah. Yet another battery then.

[@emmabird9745]

Actually, Your reply does raise another issue. How is the axle paired to the bike? The same difficulties arise when changing the wheel and axle. How does it work?

[@The_Book_Of_M]

Great video. Please keep all the details in videos like this.

[@tristramcharnley2581]

Its a miniature overdrive, I used to own a Triumph TR4 with one. A secondary gearbox bolted to the main driveshaft with an epicyclic gear arrangement operated by a solenoid. Invented in 1948. A bit heavier thann this though!

[@PeakTorque]

Similar to my tr6! Still working until the solenoid sticks :)

[@tristramcharnley2581]

@@PeakTorque yep, that solenoid had a mind of its own. Laycock fun 👌

[@62davelee]

Curious if Classified specs a maximum tire size and a minimum chain ring size? Shimano did with the Alfine 11 internally geared hub. The Alfine used used a clutch mechanism as well. I bought a used Surly ECR that was built with an Alfine 11 hub wheelset that had 29x3in tires. The chainring on the bike was a 38 tooth. Left me using the three lowest gears just trying to cruise flat pavement. I put a 34 tooth ring on and I was able to use more out the great range. But if I applied too much force it would over power the clutch. Looked up the shipped for the hub ave they recommend the biggest tire a 700x32 and a 38 tooth chain ring.

[@PeakTorque]

Yeh technically I'm not supposed to be using a 34T front, but with the 30t on the back they said it would be absolutely fine.

[@andrewmallagh3367]

Brilliant, look forward to the next one

[@calebking4443]

Great video! Can't wait for part two.

[@MAEBikr]

As a middle aged engineer -please keep this detail! Cannot wait for the real world video

[@philipk4475]

Fantastic video. Great point with the load and vibration, let's hope they take that on board. In general though I'm impressed with the hub, the efficiency loss is lower than I thought and your engineering endorsement is solid. Thanks for teaching this physicist some mechanical engineering! Love the sunwheel locking mechanism. Please go into the pawls and spring :) Looking forward to the next vid!

[@charlesblithfield6182]

I’m no engineer but I understood most of your discussion and analysis so good job on that. As far as the system is concerned I like the concept and wonder what the limitations to broader adoption will be beyond what is obvious.

[@moserroman2083]

Ah finally someone getting trough it ( other than hambibi a bit) . I've so much mixed feelings regarding this too. So will watch this very cautiously. And the following parts. I hope the next gen more integrated with trp stuff etc come soon. And hope it will work great with shimano too in the future. All independants persons I've heard test it for real ( i only did on a bike show indoor bike trainer flat pedals with sram rival axs) , tell me it work less good with shimano. Not crazy about specific cassette (they are light etc, but recon/edco stuff doesnt shift as welll as top tier sram or shim cassette imho. Plus I can't use tailfin trought axle mounting kit with the classifield non hollow axle transmission unit etc, so if no eyelets on the frame i am fucked up a bit. A very good honest bike shop friend in Germany, told me 4 out 5 of the classified wheels they ve sold have developped play issue. And as it's a black blox all closed they couldn't do shit except send it back. And even if no play issues, when the inside well protected bearings die ;you have to send it back. Wish this will get more serviceable in everyday shop in the future.

[@MichielvanderMeulen]

There used to be systems where back pedaling would change gears. It might even be a back pedaling brake system too, I can't remember.

[@timowen5772]

Great content - your approach is commended! Watched every second.

[@niklasbirksted8175]

Alex, you are my favourite Winklevoss!

[@domonkosscheiling5809]

i may be wrong about this, but both the one way bearing and the torque arm look very similar to the ones used in some old coaster brakes (i think it's a patent of sachs). i mean, the principle looks the same to me.

[@tednruth453]

I believe that Victor Campenaerts was using a Classified hub in the spring classics. Did any other World Tour riders use it ?

[@moserroman2083]

uno-x had a least one rider with it at the tour of hungary in 2023 or maybe 2022, but it didn't last

[@dominicbritt]

Very nice work PT. PS - I like my front derailleur!

[@mrwezbo]

Unrelated, but I really like your PT logo - looks great!

[@Robutube1]

Appetite for Pt2 whetted.

[@challacustica9049]

Loved this video. My big concern is still the chainline, since as a mechanic I have a dislike/fear of one-by bikes with a large number of rear gears. Will you be testing this with a one-by as well, since that's what they intend it to be used as?

[@fieldlab4]

In this design, the little sprag clutch is to prevent backwards rotation of the sun gear when unlocked. High gear is 1:1. Low gear is 1:

[@PeakTorque]

I literally explained that all in the video :) using the sprag to react the pedalling torque is novel and clever packaging but yes it could be a weak point over time. A fixed sun config is the most efficient remember, so they'd be unlikely to change that for the reduction ratio.

[@jasondurand4049]

My brain hurts, but I love it

[@williamyoung9501]

New to the channel. I've got to ask, is that into jingle hambinis normally yelled intro phrase?

[@gavinatkins3371]

Of course it is. Hambini claimed the system is 95% efficient so I’m guessing there may be a beef going on. Here for it 😂

[@echtogammut]

I can't say if I speak for your whole audience, but I like this more technical analysis and wouldn't mind it being longer. Around the 25 minute market, I was grabbing a notepad because your comment on the load placed on the BB gave me an idea for something else I was working on.

[@olekmehera7256]

Aside from engineering, fantastic seiko skx007, been around your channel since your seiko presage review ;)

[@PeakTorque]

I still have the presage in its box!

[@FrazerWorley]

Tremendous stuff, thank you

[@markyoung950]

Is there an oil port for lubrication? From my experience with Powercranks, the manufacturer did not recommend standing start sprints because of all of the high torque. Big riders getting out of the saddle can place a lot of torque on the components. Some of our customers weigh 250 lb/113 kg. The impact loads of bad pedaling. That looks like something that the local bike shop would not service. Are they prepared for warranty service?

[@moserroman2083]

it seems so , bike shop i know sent 4 out of 5 units back because unserviceable black box play issue. I like their idea especially on gravel and belgian so kinda have to support it a little but yeah mixed feelings

[@rosomak8244]

The pricing is prohibitive. They apparently don't intend to sell that. It's like the 100 complications Swiss watch, intended only to impress and create publicity for the company. It's not a real product.

[@rickrichardson1141]

This is what I’ve been waiting for

[@darrenhitchcox6345]

Awesome breakdown. I do love the idea like you you, but the cost is very prohibitive and I wonder about the long term running of the sprag clutch. I have one of these in my ebike motor (Specialized SL 1.1) that need to be changed after 5000 miles. Looking forward to the next part with outside tests

[@pauldamian2988]

Great stuff! Did I miss how it was activated?

[@RK01]

Great video, I’ve been looking forward to this series, very interested in the technology and possible future wheel investment.

[@balsa02]

So they don't even have a ball bearing at the axle of the planet gears, which are the part of the power line?

[@PeakTorque]

Planets have small needle rollers

[@davidburgess741]

If Sprag clutches are up to the job of freehub pawls and ratchet wheels, why aren't they used in cassette freehubs? Infinite points of engagement! My gut tells me this will prove to be Classified's failure point. With that price point, when the company folds, owners can bin their hubs. When those Sprags roll over when worn and under load it might not be pretty!

[@rosomak8244]

Remember the almost deterministic obsolescence of the electronics. There is a reason why this guy isn't discussing the actuator mechanism. I bet 3-4 years or maybe 10k km of riding and this thing will be a dead weight one way or another.

[@robin_stevens]

The testing of the 50-30 combination in the reduction mode will have a worse chain line compared to doing that on a single front chain ring system. Similarly, the chain line for the 34-30 run will be a bit better that on a single front ring system. No idea how much we're talking about though.

[@PeakTorque]

But 45% lower chain force and radial load on hub bearings and BB bearings. 1x will always have a lower range of combos where the chain line is optimised.

[@Apuh88]

Really good video, really enjoyed it even when i dont completely understanding it😂

[@alf3071]

automatic gear change sounds cool, how does it feel when you're pedalling?

[@badappel27]

wild idea can you still do 2x and use the hub as a third front gear

[@lask2057]

Great video, are there any updates on that open mold chinese frame you built up earlier in the year? Looking at getting a cheap carbon road bike and it looked decent

[@zachs6191]

does it rely on the needle bearings too much? sounds like the most obvious point of failure. Those tiny bearings can handle the load/torque over thousands of Ks? You keep saying they 'lock', would there be potential for slipping?

[@catflapjones2677]

Did they test the hub efficiency when it was built into a wheel (with a bunch of spokes altering the compression of the various bearings that contact the shell)?

[@PeakTorque]

The external hub shell is completely isolated from the inside part with all the bearings and gears so that's not an issue.

[@gregknipe8772]

thank you!!

[@DnDMF]

Great video PT! I like the design, except that torque arm, but I can't see the use of it - especially at those prices.

[@ledoov]

stupid question could they do the reverse of this and make it 1:1 to current gearing and then harder instead instead of reducing?

[@unbridlededification]

Fantastic. But will Hambini remain friends with you after this?

[@moserroman2083]

maybe not they are 5 of age after all

[@0pvo0]

Are you saying it works best at..... Peak Torque...? Well made video, cheers mate

[@PeakTorque]

Yes 👍

[@CatManDoSocial]

Excellent content. What is "DHCLB"?

[@mcspikesky]

Relevant to the topic at the end.. trying to figure out the best front rear sprocket combo for my single speed ebike.. I don't get how a larger front ring makes for less chain force?

[@SeaCowsBeatLobsters]

t = F * d t: torque F: force d: distance If you increase the chainring radius (distance from chain to bb axle) but you keep torque the same then the force must decrease to keep the equation balanced.

[@DanTuber]

Can you open the hub up an get a look inside it?

[@moserroman2083]

probably not ? if this unit was send for free for review, otherwhise maybe if he wanted to destroy close to 1k euro ?

[@sccxvelo]

Will Classifiedhub work better with mechanical RD shifting or is electric better with classified hub? Thank you for doing this series. May have to go classified due my cx bike only has the RD routing with the brake routing. With all the climbing where I live 2x is preferred over 1x. A FD axs battery takes up tire clearance which is for max 40mm tire clearance on the cx frame I use for general use, gravel, and cx races which impacts gravel tires. Not liking the idea of new shinamo Di2 control in the RD which will go down at some point riding offroad, so classified hub has my attention.

[@jimhize]

Can’t see why it would care if the rear mech is mechanical or electronic

[@markhancock7527]

The main point is how much more expensive is it over a normal Hub & cassette system. But i can see T.T bikes using it to save weight.

[@luukrutten1295]

How easy is it to service these things? hub bearing replacement may be a bit more difficult.

[@matthewbenger8355]

So could they tweak this then theoretically so that the ratio is different to a standard 16T chainset difference then? From your explanation I don't see why not? I think being able to have a 52 or 54T chainring even, but a 34T virtual chainring would be more beneficial as then we aren't stuck with conventional chainring sizes

[@PeakTorque]

Yes. There is scope to modify the ration, personally i would prefer a bigger jump but im not sure if they have plans to tweak the gears.

[@moserroman2083]

16 t is already massive , can't see why you would want more at the front, get a bigger casssette at the back . And if not enough just reduce the chainring size ...

[@jkausel2008]

cool... unfortunately not compatible with SRAM flattop chains

[@micktheshaggy3977]

@PeakTorque Could that torque arm be mounted with the same (slightly longer) bolt that holds the flat mounted brake caliper? On your bike it almost there (as shown at 11:38). Flat mount is located relatively to the hub axle, so only few types (two?) of such tabs would be needed (for 140 or 160 mm flat mount). Just thinking out loud.

[@PeakTorque]

It could, but the height of the flat mount tab is not set by any standard. So there a few different heights of torque arm that are supplied. Then the arm just bears on the cap head of the bolt. Some of the torque is resisted by clamping the end caps and their friction, any excess is reacted by the brake mount.

[@Surestick88]

Is there any advantage of having the planetary gears in the hub vs. in the crank area (like they did for Hammerschmidt)?

[@danielakerman8241]

Having it in the hub doesn’t require any modifications to the bike frame or the Q factor

[@biturboism]

The Hambini intro really struck me

[@alexmites]

would the losses be the same when taking into consideration the improvement on chainline on a 1x chain and chainring combination vs 2x at big to big combination?

[@JustSnowglow]

I really hope this catch on. I would hapily trade a MTB drivetrain for a "dinglespeed" setup using a hub like this.

[@luukrutten1295]

Would it be possible to create a better version of the truvativ Hammerschidt cranks with this Classified technology. Those cranks mostly worked opposite, making 1;1 the lighter gear and going up to 1 - 1.6 for the harder one, creating substantial drag.

[@tristramcharnley2581]

If only this could work with Shimano synchronised shifting

[@moserroman2083]

it's on the way , update version collab with trp

[@48ford8n]

Isn’t this just a 3 speed IGH ( that’s been around for over a hundred years) attached to a cassette spline?

[@moserroman2083]

2

[@donwinston]

❓(Mechanical engineering ain't my thing) How long before it wears out?

[@pagosa1040]

Could be a big upgrade for " single speed " riding in the mtns.

[@NeoPayneHK]

would like to know will it break

[@moserroman2083]

it has a tendency to developp unfixeable play

[@Alan_Hans__]

Great video and very nice bit of gear. Personally I hate ball drag.

[@huibsmeets8564]

Nice explanation and thoughts. Even owing a bike with a rohloff hub myself, this classified hub is a no go for me. It’s a too bolt-on solution considering it’s not really integrated with the SRAM/Shimano electronic shifting. Cassette choice is only what classified offers (although expanding). What about shifting performance thinking about patented Hyperglide as an example? What if you put your 1-by bike + this hub on your direct-drive trainer ;-)

[@GeorgeD1]

I am not trying to be smart - just wondering - a 0.7 ratio is closest to a 52/36 chainring (0.6923), but a 50/34 chainring has a ratio of 0.68, so slightly closer gearing there. Does the size of the chosen single chainring at the front affect the efficiency and perceived performance of the hub?

[@moserroman2083]

no it doesnt affect the efficiency and perceived performance of the hub, only of the rest of drivetrain like others usual 1X and 2X transmissions