Intra Drive's Combined Motor & Gearbox Fits Bikes Designed For Shimano EP8 [Updated on expanding into the aftermarket]

Nov 22, 2023
by Seb Stott  
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We first spotted Intra Drive at Eurobike 2022, but we now have some more details on the Scottish startup's product that's aiming to disrupt the e-bike drive unit market.

Firstly, it combines a motor and an 8-speed gearbox into a single unit, eliminating the conventional external derailleur drivetrain which can be exposed to damage, requires regular maintenance, and wears more quickly when used with a motor. Secondly, and perhaps even more intriguingly, it uses the same form factor as Shimano's popular EP8/EP801 drive unit, which means it can be fitted to the same bikes. Thirdly, the product is designed with an emphasis on sustainable construction, longevity, repairability, and recyclability. The company even has "Nature" on the board of directors.




Motor specs

The drive unit promises 600 Watts of peak power (250 W nominal) and up to 350% assistance. The torque will vary depending on which gear is selected, so this can't be directly compared to other systems, but assuming the peak power doesn't come at ridiculously high cadences, it should have enough oomph to compete in the "full power" e-bike category. The automotive-style gearbox has eight speeds with a 473% gearing range. The gaps between gears are nice and consistent at 18.4 - 20.8%. There are spur gears made of hardened steel that are changed with an electronic actuator, apparently in just 100 milliseconds. The drive unit weighs 4.5 kg, which is about 1.8 kg more than the Shimano EP801, but remember that includes a gearbox.

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The system includes a bar-mounted display and remote (top left) to control the gears and power modes.

The unit can be combined with a chain or belt to transfer drive to the rear wheel. Two systems already exist which combine a motor and a gearbox into a single mid-drive unit, (Pinion and Valeo) but what makes the GD8 unique is that it fits all that into the same form factor and mounting bolt pattern as Shimano's popular drive units, meaning it can be fitted as an alternative option (like spec'ing a bike with either a Shimano or SRAM drivetrain).

It would be great to see an aftermarket option for Shimano owners keen to try a gearbox-based system, but Intra Drive are currently pursuing a Business-to-Business (B2B) model, supplying their system to bike manufacturers so they can offer different motor specs out of a single design. We love the idea of consolidating motor mounts in the eMTB space, but it’s not without issues in the aftermarket—the small chainring size especially may not play nice with some suspension designs. Shimano’s mounting system is open and available for others to use, but we have to assume it will void most frame manufacturers’ warranties to run a motor their bikes weren’t officially designed around. At least for now.

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How Intra Drive sees their system fitting into the e-bike market.

The 24-tooth drive chainring is smaller than most ebike drivetrains (which typically use 32-36 teeth). On full-suspension bikes, this will affect the suspension performance by increasing the interaction between the chain tension and the suspension movement (anti-squat), which may not be ideal with some suspension designs - this is something frame manufacturers will need to bear in mind. I asked Intra Drive why they went with this smaller chainring/pulley wheel:

bigquotesThe chainring is relatively small at 24t, this is driven by some other parts in the product which constrain how large we can make the chainring. However, this doesn't impact on the gear ratios as we simply size the rear sprocket to achieve the overall ratios we need in the design. We are running a wide single-speed chain on our prototypes, with custom sprockets - this ensures long life despite the relatively small chainring. The chainring rotates at different speeds relative to the cranks, depending on which of the 8 speeds is selected. For example, in 1st gear, the sprocket rotates slower than the cranks, whilst in 8th gear it will rotate 2.4x faster than the cranks.Intra Drive



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Sustainability

Intra Drive claims to have "set out to achieve the lowest environmental impact possible over the lifetime of the product". They aim to achieve this in four key ways: "Longevity and repairability; long-term availability of spare parts; minimise embodied carbon emissions; power the e-mobility revolution".

Yes, the GD8 motor is not just for off-road playthings (eMTBs) but also for powering commuter bikes, e-cargo bikes and Light Electric Vehicles which could reduce the use of cars and vans, especially in cities.

Recently, Intra Drive announced that they would appoint "Nature" to the board of directors - an unusual move but one which has been done before by fellow Edinburgh-based brand Faith In Nature. I asked Intra Drive what this means in practice:

bigquotesA company’s success is dependent on having a healthy planet upon which to operate. So giving Nature a seat at the decision-making table can help a business to thrive, whilst respecting planetary boundaries. In practice, we will need to recruit a Non-Executive Director to our board, whose job will be to represent the interests of the Natural world, and who will have equal influence on strategic decisions to other board members. We are not the first to do this - we have been inspired by other forward-thinking businesses, and we hope our radical stance will motivate others to rethink the way we do business.

The two links below go into more detail on this. The first article covers the rationale behind appointing Nature as a Non-Executive Director, whilst the second one provides some more practical detail on how Faith in Nature implemented this.

One thing worth highlighting is that this unusual and bold move was driven by the lead investor of our current seed investment round, who requested we implement this, which myself and founder Mark fully support.
Peter Slotwinski, Intra Drive Co-Founder



Intra Drive is currently in the industrialisation phase, testing pre-production prototypes and building a European supply chain. They expect to see bikes on sale with the GD8 powertrain in early 2025.

For more information, head to intra-drive.com

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Update on expanding into the aftermarket

bigquotesWe would very much like to go down the aftermarket route in the future because it is in line with our circular economy aspirations, and because we get asked this a lot - it's clear there is demand. Our plan is to sell B2B initially, then enter the retrofit market once we're established. The reason we're not doing it just yet is because our unit sits slightly deeper into the bracket and we found that it doesn't fit every EP8/E8000 frame out there. We have a product roadmap to shrink the unit ever so slightly to make it fit more frames, but we still have the issue of chainstay clearance on full suspension bikes due to our smaller chain ring and because our unit is wider than an EP8/E8000, it won't fit carbon frames that tend to wrap around the sides of the drive unit.

We stand a pretty good chance, however, of supplying hardtail, cargo and commuter bikes as an aftermarket option. It would also stand to reason that we would make a Bosch Gen2-3 compatible version as well.
Peter Slotwinski, Intra Drive Co-Founder


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Member since Dec 29, 2014
287 articles

143 Comments
  • 92 4
 They is great to see. The small chainring will limit suitability from EP8 to IntraDrive on eMTBs, but really nice to see some more MGU options on the horizon. I don't love gearboxes on conventional bikes, but most of their downsides are avoided with e-bike systems.
  • 38 1
 I've been holding off on buying an ebike until the MGU tech has been proven. Makes so much more sense having the motor and shifting integrated. Great to see more options coming to market.
  • 5 1
 @thebradjohns: Exactly. I am sure there'll be only bikes exactly like this in the not so distant future.
See the drivetrain silhouette, and overalls even the Orange bike is nice this way :-).
They mention some patented gear shifting mechanism, I must study that !!!
  • 21 21
 "I don't love gearboxes on conventional bikes"

Why? Have you spent a lot of time riding one?
  • 6 1
 Brilliant. Good luck to them. Would love a conversion kit for existing Shimano powered bike...
Curious, is this going to have more anti-squat due to smaller chainring size?
  • 13 0
 Idgaf if my anti squat would be a little weird.

If I could buy this, bolt it on to my Decoy and plug it in to the existing battery, I’d order one right now.
  • 5 1
 @rojo-1: Seems like battery and controller would be the issue, but not insurmountable. Judging from how many motors and batteries my friends with ebikes have gone through, I'd guess there's a pretty giant market.
  • 2 0
 Can't you just run a bigger chainring and larger rear sprocket?
  • 12 3
 @MorganBH: I totally see the value in them, and understand why some people see them as the future. But, I've spent enough time on the current generation of gearboxes to know they're not for me—yet.
  • 2 0
 SOMEONE TELL ME ABOUT THE Q FACTOR
  • 7 0
 Who woulda ever thunk it’s first application would be to open and close a barn door.
  • 2 1
 The problem with small chainrings isn’t an issue.. If there’s still a bike offered without an idler in 2025 it’ll be unsellable and unrideable. Trek told me so!
  • 1 0
 this is great, really differentiates between a bicycle at maximum efficiency and a motorcycle at whatever % because it rips
  • 1 3
 @MorganBH: you don't need to spend a lot of time on one......a couple hours will enilighten you to all the drawbacks....and the advantages. I am not shitting on gearboxes, but brian is correct here. their drawbacks are extra sucky on a non-assisted bike.
  • 1 0
 Im very much "wait and see" for all these ebike-gearbox stuff because a lot of it is arm-chair-hype. But it's really nice to see people try to do it. Super curious how well that'll really go in practice.
  • 6 0
 @sngltrkmnd: Q FACTOR IS A DIMENSIONLESS PARAMETER THAT DESCRIBES HOW UNDERDAMPED AN OSCILLATOR OR RESONATOR IS
  • 10 2
 @sngltrkmnd: The "Q" stands for Quack, as in a duck. The Quack Factor is a silly way of seeing how much of a waddle position your feet are in on a bike. Them silly roadies have their feet narrower than their hips - no wonder they can't descend a smooth tar-sealed hill quickly.

Quackity quack quack, mother duck!
  • 1 0
 If it’s possible to change the front cog to a larger size, then you can just go bigger on the single rear to match. Solves the gearing issue and anti squat problem. But reduces ground clearance.
  • 1 0
 So am I right in saying that whilst it shares the same mounts as the Shimano motor, it probably won't work well on a frame originally designed with a Shimano motor in mind, because the chainring size has an impact on the suspension kinematics?

I know nothing about suspension design, would that be the same for all suspension designs (4 bar, VPP, singe pivot etc.)?
  • 1 0
 The 24t chainring is independent from the gear ratios. you absolutely can have a 24t chainring with a gearbox that mimics a 32t with 50t cassete. And 473% range is bigger than a 50/11 cassete!
  • 1 0
 @mattg95: The housing of the motor sticks out in front of the front sprocket so no, it would hit.
  • 1 1
 @handynzl: Absolutely hilarious comment. Pretty sure you've never gone 65 mph descending on a mountain road in a group.

You'd be off the back, or more likely, off the road.
  • 2 0
 @danger13: Well, actually I have. I have raced both road and MTB nationally in my younger years. Top speed I've hit was 97kph on rim brakes. I have a loop I do from my house where I hit 75-80kph down a certain hill every time I ride it.

I wonder are you of German descent and take all jokes literally?
  • 1 2
 @handynzl: If you've actually road raced your comment makes even less sense. Of course, if you raced "nationally" in New Zealand, I'm sure you must know what you're talking about.

By the way, I made it to the US nationals for 10 years straight, both road racing and time trialing. And I'll freely admit I was nowhere nationally.

Not sure what the joke you were referring to was? Oh, by the way, all the speeds you referenced are slower than the speed I mentioned, which I have topped on numerous occasions. Do I win the contest?
  • 4 0
 @danger13: You sure do! You win a bag of Jelly Babies.
  • 48 2
 Checks all the boxes. Even the elusive “informed by circular design” box.
  • 18 1
 Informed by triquetra design or nothing for me thanks.
  • 5 2
 It’s lol time

If someone else had picked the down selection keypoints let see.

SHIMANO massive resources massive support massive user base
Bosch massive resources massive support massive user base
Pinion SELF SUSTAINING resources support & increasing user base

Startup hoping to crowdfund and having burned through all the eu and uk grants they could get

I reckon this will belong to someone else in under a year in the current economic climate
  • 3 2
 @thewanderingtramp: my thoughts exactly on this one sadly, they took too long to get to market, took up every grant going and now the tech is falling behind. See this all the time in my line of work outside the bike industry

I noticed a massive shift in their marketing as soon as pinion dropped their new drive unit.
  • 38 0
 Hopefully that becomes an aftermarket option, marketing to all the shimano ebikes out of warraty with a serviceable motor would surely be easy pickings, and is easy to justify compared to chucking a whole bike away and buying a new one
  • 4 0
 Anyone know shimano offers replacement motors out of warranty, and the cost? Have been very curious about this before my warranty expires…
  • 4 0
 @Betacygni: a lot people have managed to get one for free up until 4 years from purchase. Mine died around 4 years but had 15k km on it so they didn't give me any discount, 1000€ fitted at a random shop (I had bought the bike direct)
  • 2 0
 @Betacygni: yes 800 in the uk
  • 1 0
 Unfortunately this isn’t allowed in the EU without manufacturer homologation.
  • 3 0
 @FatSanch: who will be checking though?
  • 1 0
 @mashrv1: in Gernany, they check. But it also means they can’t advertise it as aftermarket.
  • 1 0
 @FatSanch: who is “they”?
  • 36 3
 Hi folks, Mark from Intra Drive Ltd here.

Just to let you all know we are currently raising investment to enable us to take the product to market, and have a campaign on Crowdcube which is ending TONIGHT! The campaign closes at midnight (UK time).

For potential investors who share our vision, and are already registered on Crowdcube, please see our campaign pitch here: www.crowdcube.com/intradrive

Unfortunately if you're not already registered on Crowdcube you won't be able to invest in this round as it takes 24hrs to register. But please head to our website and sign up for email updates (don't worry, we won't send out spam, only occasional updates of significant mielstones etc). www.intra-drive.com

We'll remain open to larger (£10k+) investments after the Crowdcube round closes.
For further info, drop us a line: investment@intra-drive.com
  • 4 2
 Good luck with it all. I there a retro fit for Bosch equipped bikes in the pipeline?
  • 63 0
 I am also open to £10k+ investments. No closing date.
  • 4 2
 I spoke to you guys, maybe even yourself, Mark, at Tweedlove last year. Really appreciated the time taken to explain this awesome product. I love the ethos behind the company as well
  • 3 1
 Awesome! ALWAYS root for the little disruptor guy! Here's hoping you guys crush it!
  • 17 0
 This is what e-bikes should have been from the beginning. No need to make T-type happen to handle e-bike loads. No worrying about the potential drivetrain losses from the gearbox. No need for extra batteries NOR wires to enable electronic shifting. This is the way.
  • 1 0
 Possibly…. There is extra drag and it will likely suck really hard to have to pedal past the speed limiter to clear a jump. Even worse for European countries.
If the limiter was removed, now we’re talking. Just need a battery with a bit more capacity to offset the extra drag
  • 6 0
 it would be interesting to have a bike that allowed a gearbox/motor like this one that can be swapped out for a non-motorized gear box. Just a few bolts and remove/reinstall the battery and you’ve essentially got yourself two different bikes.
  • 2 0
 This!! Forestal bikes has something like that to convert his e-bike into a normal Enduro for their racers, don't know If it's available aftermarket
  • 3 0
 I think the Lapierre e-Zesty allowed to take out both the battery and fazua motor, to ride it like a totally non-motorized bike. I thought it was brillant, but I think the idea was not very succesfull or it didn't get known enough to reach the potential customers
  • 5 0
 Re the chainring, It's not the number of teeth that matter, it's the diameter. Even though it's only 24 tooth, its belt drive and I think the teeth are much larger. I bet that's equivalent to a convention 28t chainring diameter. Someone pls measure.
  • 4 0
 The opposite, actually.

The pitch of gates belt is slightly shorter than a bike chain, so the outside diameter of a 24t belt sprocket is just over 82mm, while a 24t chainring is 104mm.

I was surprised by this when I got a belt drive -- my 46t sprocket is similar to a 38t chainring.

www.gatescarbondrive.com/~/media/files/gcd/gates-tech-manual-en.pdf
www.wolftoothcomponents.com/pages/chainring-diameter-by-tooth-count
  • 1 0
 Caught me on lunch! Just checked, they’re actuallly smaller. 24t Gates cog diameter is 82mm. Similar size to a 20t traditional cog.
  • 3 0
 A little of the difference is made up by the fact that the belt sits more on top of the teeth than a chain does

I mean, a belt + sprocket is larger diameter than the sprocket alone (5-10mm at a guess?)

But a chain + chainring is bascially the same diameter as the chainring alone
  • 1 0
 @overconfident: I’m not sure that’s relevant. The top of the belt rides a bit higher, but where the force is actually applied to the ring and cog (rollers or belt nubs) is basically the same for either. I’d think it’s the force vector from input to output rather than the top of the physical driveline that matters. Accounting for a bit more force applied to the base of the nub due to deflection I doubt the “effective diameter” for anti-squat purposes would be more than a couple mm different.
  • 1 0
 It looks like the prototype was belt drive, the finished product (as shown under Intra Drive's quote) shows a conventional chain. Also, the quote mentions using a wide single speed chain with custom sprockets.
  • 2 1
 @gnarnaimo: why would they design a system designed to work on suspension bikes with apparently a 20t cog equivalent actual diameter? 30-34 is the standard. @Intra ?
  • 2 1
 @flattire: I imagine they needed the space. Trying to get a motor and gearbox into a similar space to just a motor they look to have gone out sideways just in front of the sprocket.
  • 1 1
 @kevinjordans: I was just thinking about clearance really
  • 8 0
 Shimano management: "Quick, change the frame mounting points!"
  • 11 0
 I asked Shimano about this and they're apparently fine with others using the mounting standard. Apparently there's at least one other OEM motor brand doing a Shimano-mount standard motor already.
  • 1 0
 @brianpark: That's great to hear, but how long until Shimano changes them on their next motor?
  • 3 0
 @brianpark: I'll likely never own an e-bike but i'm not against them, but as someone that recently got back into modern mtb tech and likes to nerd out on it, I was surprised there wasnt a standard for e-motors! Other than money, the next biggest reason I wouldnt invest in a current e-mtb is the lack of standards. Buying a bike with a part that cant be swapped out or upgraded is really 1990s style technology. Thats like buying a bike and realizing the shock or fork is proprietary and cant be upgraded. How are smaller companies supposed to gain traction in the market when companies have to design a frame around one or two proprietary motors?
  • 5 0
 This is the right direction for me. It will be a happy day when I pull the trigger on a commuter ebike with one of these unit construction drives.
  • 7 4
 “Non-Executive Director to our board, whose job will be to represent the interests of the Natural world, and who will have equal influence on strategic decisions to other board members”

What could possibly go wrong with this^?
  • 2 1
 When they said "Nature" I thought they meant the academic journal publisher...

The truth seems to be even more weird.
  • 2 1
 These sustainability executive roles at other companies are frequently jettisoned when the costs of following their recommendations directly conflict with other objectives, usually profit or the company’s outright continued existence. Even when that doesn’t happen, your sure to attract haters that will vocally note when they believe you have acted hypocritically in respect to your environmental policies or values.

In light of this, I would recommend avoiding this sort organizational structure or public statements. Doing so doesn’t prevent you in any way from achieving your environmental objectives. So, by all means, please be environmentally responsible with how you operate your business, just remember that these kinds of statements can actually get in the way of accomplishing your environmental aims by inviting criticism as well as unneeded scrutiny and the potential for the spread of misinformation about your environmental work and the motivations behind it.
  • 3 0
 I love that when they talk about sustainability, they specifically mention repairability. I hope they follow through on that with easily available replacement parts and well documented repair guides.
  • 2 0
 Oh.. being a former motocross rider who has found his peace of mind in the years (20 or more) into traditional MountainBikes.. That Orange is looking gourgeus... and for the very first time.. I am willing to put my legs over an E-mtb.. Just to say...
  • 3 0
 Small output seems like it would work great with an idler gear for a high pivot design. Or could they just enlarge the rear sprocket more to get a larger front?
  • 2 0
 I was thinking the same thing - a single larger sprocket in the back does not incur a huge weight penalty, and it spreads out the load a bit more, so it might last longer anyway. The way they packaged the motor casing vis-a-vis the chain ring, though, limits the size to what they currently have. Which makes me think that perhaps e-MTB was an afterthought here - the small chainring doesn't matter with commuter/cargo bikes w/o rear suspension, and they might just think of that as their volume market.
  • 1 0
 Cool idea with retrofitting but it's all nothing if your current battery isn't able to power it, no mention is made of any compatibility. I have a YT decoy and would definitely consider something like this as a future- proofing if and when my motor failed if it was able to use my YT battery.
  • 4 0
 I might change my name to Nature, should be able to snag a few board appointments...
  • 1 0
 Really cool to see a different option and from Scotland too! The USP of Shimano mounting really sets it apart but how have all the smart people developing this missed that the small chainring size undoes this.

Frames with the ep8 motor have kinematics and tubes that are designed around a much bigger chainring so if it's not an Orange then the chainstay will probably be in the way meaning you cant fit the Intradrive, and if it doesn't get in the way then the pivots will be in the wrong place for optimal suspension performance, either way frames would need a redesign around the chainring, rendering the whole USP of interchangable mounting without a frame change useless, you may as well redesign the mounting points at the same time and fit the more proven/supported pinion box.

I'm rooting for the startup to disrupt the market but the reality is without the same chainring size the interchangability that makes it stand out, doesn't exist.
  • 1 0
 If youre going to put a motor in, makes sense to add a gearbox too

And the reapairability/Shimano mount standard for s music to the ears of mtbers sick of incompatible standards

A bigger chainring could see it really take off (or if its good enough bikes designed around it)

Be very interesting to see if this became a settled standard whether regular bikes would go gearbox too
  • 1 0
 move the pulley mount to the top of the motor (can straddle the top run of belt like a conventional chain guide does), so it opens up the ground clearance below, and you got a winner. This bolt-on solution is what the industry has been waiting for....
  • 1 0
 Well, it looks like their aftermarket availability will be around the same time as the Pinion MGU will have that availability - if that.

Bummer in a way, as I have made Shimano EP8 frames, and, think they would not have problems with the 'deeper / higher' top section of the Intra Drive that Mark from ID mentions above.

One problem I see with the Intra Drive, is how the RH side case 'wraps' further back around / over the Chainwheel. That Will limit it's fitment on quite a few frames, especially many with a high / forward pivot frames, with an Idler wheel. My frames are like that - well, not that high, but well forward. So, an extra Idler would have to be placed to have the chain go 'back' then forward / up to the original idler.

I can of course make a different frame design, but that problem, that Intra Drive have not given thought to, and the (my assumed) aftermarket (and hence, small frame making businesses like mine) availability being near the same as the Pinion, well, my interest in the Intra Drive has lessened, Considerably. But, we'll see how it all pans out, I guess.
  • 5 4
 Small front ring is fine as this opens space to pass over objects easier. Simply set up your gear range from the rear sprocket size.....Good to see this design and its shimano size compatible!
  • 5 0
 The problem is anti-squat and pedal kickback. This is especially an issue on e-bikes as it is difficult to drop the main pivot down with the motor in the way. There could be a solution to go larger on both the front and rear sprocket if they manufactured it. I'm guessing the limitation is that with the packaging they can't fit quite a big enough reduction gear to run a large front chainring and a standard rear sprocket.
  • 2 0
 How does it compare?... to the french Effigear-Valeo combo.
www.effigear.com/fr/content/24-valeo-cyclee
Let's compare them in reality. That would be interesting...
  • 4 0
 It doesn't compare. It is twice smaller than EffiValeo.
  • 2 2
 Great! Brilliant to see some innovation on this front from a go-ahead Scottish company. Interested in investing some $ in this as the ability to fit in place of a Shimano motor is huge! One massive issue tho' - lads, get a proper Graphic Designer in to design a decent logo...please. I'll do it for gratis.
  • 3 0
 You don’t like their logo with the long d? I mean, who doesn’t like a long d?
  • 2 0
 Shimano should be investing in this company and some point buy them outright and they will have the moto-gearbox perfected, ready for production and offer it as a kit.
  • 1 1
 Finally a manufacturer that is going to provide sustainability, repairability, availability of spare parts. In addition by making the motor/gearbox with the form factor of an existing motor brand such as Shimano is great because this would force the e-bike parts to be compliant to a standard form factor. No, it's just getting manufacturers to make standardized form factors.
  • 1 0
 This is really cool. Would love to see this type of thing retro-fit on bikes that break a motor, etc. I just wonder about battery compatibility, electronics, etc.
  • 1 0
 I hope companies eventually come together to make a standard "universal engine mount" kind of like the universal deraileur hanger.
  • 1 0
 See how long that took tho. This idea is far too common sensical to happen any time soon.
  • 2 0
 How efficient is it?
Is it as efficient as a Rohloff for example?
  • 4 0
 Doesn't matter as much with a motor to help you.
  • 2 0
 Pinion gearboxes are only a couple of percent less efficient than a rohloff, but they're 100% better for offroad applications. The minimal efficiency loss shouldn't matter with a motor.
  • 1 0
 @joelsman: I assume you don't have an ebike.
I asked, because if you don't desresctrict the bike, pushing an ebike after 25km/h you push more watts into those pedals than on a bike.

Unfortenatly I can't share actual numbers, since I;don't have a power meter, but for the same effort (feeling):

Ebike: you'll cycle around 32/33km/h
Bike: you'll be close to 40km/h

And air resistance increase with square to the speed (assuming same area).

Drivetrain efficiency, also will have effect on the battery range, so it's not that simple.
  • 2 0
 @MorganBH: I asked about Rohloff, becuase if you use on bike, you'll notice the drag.

Even if it's only 2...3% difference.

And Rohloff when new, is really PITA on this
  • 2 0
 @TDMAN: I don't have an ebike but have ridden one a couple times. Think here in the states the top speed of assist is higher, so not as bad here, but I have run the battery completely out and had to pedal about a mile some uphill and that did stink. This was a transition repeater with shimano motor. My wife has a hub motor commuter bike with a top speed of 30mph with asist but that bike is a different class.
Anyway I see what you're saying and that does have some importance that I had not thought of.
  • 1 0
 @TDMAN: Got you on this. Riding a Rohloff, a Effigear gearbox, an E-Cargo bike with shimano ep8 + shimano gearhub and standard 1x11 shifting, I would say: The e-bike with cheap gear hub feels shit (with motor turned out), very noticable drag. However, at least it is extreamly robust, appart from the gearhub cracking around, ha!
The rohloff works much better.

In this direction I think combining shifting and motor like pinion, valeo or intradrive will work best.
I'm quite happy with the effigear gearbox. There is drag, but having the chain straight without an idler is super nice in the mud. Chain stays clean and smooth. Instead, I'm running lighter tires which compenstes a little bit for the drag. Getting used to it anyways.

Currently I would never ever combine a motor with a chain shifter in the back. Thats just... nope. The shimano gear hub (nexus 5 speed) is no alternative either Big Grin
  • 2 2
 @TDMAN: Drivetrain losses typically differ in a single digit percent range and make up only a minor part of your total resistance past 25 km/h (aero being much, much larger). So as long as it's not outrageous, it's really not critical.
I'm too cynical to believe in "you notice the difference" statements, even if they were perfect apples to apples tests (which they almost never are), confirmation bias is a reality.
  • 1 2
 @Muellbeutel: yeah, you feel it!
Thank you for sharing.

But just some food for though...

Drivetrains markeyt is presently owned by Shimano and Sram.
Neither have internal gearbox, and both, will maintain the wheel rooling, until some real radical company starts to sell internal gearbox like hot cakes.
I don't forsee that for at least some years from now.

Ebikes have a BIG problem regarding reability.
There are all kind of problems, much associated with new tech...
Also, ebikes are still ubber expensive!
To make it less expensive, manufacturers will have to work on ramping up production, sorting all problems. This will automatically lead to lower prices, due to mass production and quality cost reduction

Then, we have the Batteries. And against what people predicted, prices are stable, and power/weight is also stable.
We need lower cost batteries, and higher energy with less weight (like all electrical things with battery!).

Manufacturers such as Shimano and Sram, will work towards this problems, gaining much more market, as prices goes down.

Who wouldn't have an ebike (a good one), if it cost ±800euros more than the equivalent bike?

Internal gears may appear at the very high end, but it will be so few, that it's easier to find the golden pot at the end of the rainbow
  • 1 2
 @finnspin: you don't know what you are talking about.
Please try and experiment, then you may enter and discuss.

Until then.... LOL
  • 2 0
 @TDMAN: I've owned several bikes with internally geared hubs, test ridden bikes with pinion any chance I got and own bikes with derailleurs and one with a Shimano IGH currently. Differences from for example riding position are much more noticeable in their effect on top speed for me than drivetrain, which also is what the data says from people who test efficiency.
Btw, whether you have a 100% efficient drivetrain orone that is 50% efficient, that e-bike motor resistance won't change (because why would it).
  • 1 0
 @finnspin: you are a force of nature, to not notice that.
Bless you and all the ground you smash with your holly tires
  • 1 0
 @TDMAN: I'm more impressed by the people who will notice a 4% difference and can pin down precisely which component it came from.
Most people couldn't accurately gage their power output or speed within 10% (that's why even tour de france riders use headunits and powermeters) without data, to then go and notice much smaller efficiency variations is insane.
But bless you if you somehow have a god like awareness of your body, that is a real superpower.
  • 1 0
 @finnspin: Once you try, you'll know.
I'm not saying it's 4%, 3%, or even 10% efficiency difference.

What I've stated since the begining, is that it's a noticeable difference with this:

- pushing an ebike beyond the speed limit - you will feel the motor drag
- pushing any hub gear bike, with similar tyres and weight - rohloff/sturney/shimano (never tried sram/sachs).

It's like the iddler pulley drag.
Some swear that they notice the drag, others will say it's BS.

Take care... carefull with those step climbs, pedalling standup!
Chains have a limit
  • 3 1
 Great design, but why did they install it on that orange filing cabinet?
  • 2 0
 Both UK brands
  • 1 0
 That things gonna have a lot of belt growth
  • 2 1
 only cool thing abut this thing is the belt drive.
  • 1 0
 How did Jessie May Morgan not write this article?!
  • 4 3
 Another step toward making motorcycles!
  • 1 0
 Can I get a 2 stroke version?
  • 1 0
 I 100% would buy one and try it out.
  • 6 5
 No motorless-option?
  • 1 1
 Dinnae teach yer Granny tae suck eggs
  • 1 0
 What’s the cost?
  • 1 0
 needs a narrow wide
  • 2 1
 Pros: It’s gr8
  • 4 4
 Great more Mountain Moped technology.
  • 1 2
 Awesome concept for sure! but the final drive is too small and will not work well with most suspesion designs.
  • 1 0
 seems a great idea!!
  • 1 2
 i would not be willing to help someone install one of these
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