Electric bikes are becoming more popular by the day and for good reason – they’re good for the environment, convenient, and provide a healthy alternative to other modes of transportation.
They’re also a lot of fun to ride.
As e-bike popularity grows though, so does the competition between providers for their piece of the expanding market.
Some brands are offering interesting features or fun attachments, while others are distinguishing themselves by including higher-end components on their e-bikes.
One such component is the internal gear hub, which a few e-bike providers are using to replace the traditional derailleur so many of us are used to.
The general idea is that by housing the gearing system internally, you protect it from damage and debris that can easily cause harm to an external derailleur.
This sounds great, but we all know there’s always a downside – well, in this case, that downside would be increased cost.
The question then, is whether or not internal gear hubs are really worth the extra cash.
Well, that’s what I’m here to help you figure out.
In this article, I’ll go over what internal gear hubs are and how they work; I’ll also discuss the pros and cons of switching to an e-bike with an internal system.
After reading, you’ll know whether or not it makes sense to invest in one for yourself.
Alright, let’s do this.
What Are Internal Gear Hubs?
As the name might imply, an internal gear hub (IGH) is a setup where all the different gears are placed inside the rear tire’s hub.
This is opposed to the classic derailleurs where we can visibly see the gears sitting on the outside of the bike’s rear tire.
Both setups act to change the gear ratio while you’re pedaling, but they go about it in very different ways.
I have to imagine we’ve all had a multi-speed bicycle at some time in our lives, so we all likely remember the “clanking” noise that happened anytime we changed gears.
Well, that noise is the chain being moved from one sprocket to the next, hence changing the working gear.
With IGHs, there’s a completely different mechanism.
It’s fun to imagine a tiny little derailleur somehow fitting inside that wheel hub, but that’s not how it works – there’s actually a bunch of interconnected gears that become engaged or disengaged depending on what gear you’re in.
The folks at Bike Radar do a much better job describing how these IGHs work internally, so if you’re interested, I encourage you to check out their guide on the topic.
But they basically compare it to the automatic transmission of a car.
On the outside, an IGH looks a lot like a fixed gear bike, since it’s lacking a derailleur, but don’t be fooled – IGHs can offer as many gear options as any derailleur and more.
IGHs come with various numbers of speeds, ranging from 3 – 14 generally, but now there are also some that offer “continuous variable transmission”, or “CVT” as well.
With CVT, the IGH uses metal ball bearings instead of internal sprockets or cogs, giving you the ability to make really small changes to the gear ratio.
The Enviolo Trekking IGH found on Ride1Up’s Prodigy V2, for example, uses tilting ball bearings to transfer power from the external sprocket to the rear tire.
You can imagine how subtly changing the angle of the tilt affects how much power is being transferred, thus changing the gear ratio.
It’s pretty brilliant stuff.
The result is basically a drivetrain with unlimited gear ratios.
Personally, this reminds me of a micro-adjustable resistance system on an indoor cycle, where you can make really small adjustments to the resistance, but there aren’t any numbered resistance levels.
Advantages of Internal Gear Hubs
Ok, so with an IGH, you have all your gears tucked neatly into the hub, but so what – what, if any, benefits does this offer?
Well, there are a few.
Protection
The most obvious advantage of having your gear system internalized is that it protects them from the elements while riding.
This includes protection from getting bumped, scratched, or otherwise damaged from making contact with the elements.
But it also protects the gears from getting dirty from the environment or rusted from weather conditions.
Low Maintenance
Derailleurs work well, but sometimes they need to be adjusted to optimize chain movement to improve fluidity of changing gears and reduce noise.
With IGHs however, there’s very little maintenance.
You don’t have to worry about adjusting derailleur alignments or any of that stuff because it isn’t necessary.
Some IGHs will require a little oil here or there, but that’s about it – otherwise, these systems are incredibly low maintenance.
Smooth Adjusting From Any Position
Being protected from the elements and being low maintenance are great perks, but more importantly, IGHs function superbly.
Not only do these gear systems provide smooth, virtually silent gear adjustments, but since the internal gears are always engaged, it means you can change gears as much or as little as you want without any huge drop-offs.
It also means you can change gears from a dead stop – you don’t have to be moving to change gear.
This comes in handy if you’re stopped in traffic or have to stop for some reason during a climb.
Belt Drives
And since IGHs have a single-speed design outside of the hub, it makes them compatible with belt drives, as is seen with most e-bikes using these setups.
Belts tend to be quieter and more efficient than chain drives and they require less maintenance as well.
Automatic Transmissions
Finally, I mentioned that some IGHs have CVTs, or continuous variable transmissions, where there are essentially unlimited gears available.
Well, some IGHs are also compatible with automatic transmissions, meaning they can change gears automatically just like an automatic car.
Systems like Enviolo’s Automatiq utilize an electronic gear hub which connects with an app, where you set your desired cadence.
The IGH then changes gears automatically to maintain that cadence as you ride.
Pretty amazing stuff.
Disadvantages of Internal Gear Hubs
If you’re thinking “IGHs sound great, why don’t all e-bikes come with them?”, I hear ya – well, like everything else in life, they aren’t perfect.
They have their downsides too…
Price
The biggest downside to going with IGH is the price: e-bikes with these tend to be more expensive than ones with traditional derailleurs.
But costs on IGHs vary depending on the style and brand.
Rohloff, for example, is kinda considered the gold standard when it comes to these hubs and their IGHs cost upwards of $1500; Eviolo on the other hand, has IGHs starting at around $200.
Going with an IGH with more gears (or CVT) typically increases price, while going with fewer gears usually reduces price.
Weight
IGH’s tend to weight quite a bit more than derailleurs as well, so if weight counts, this could be a concern.
An internal gear hub can easily add 2 – 5 pounds to your bike’s total weight, so if you’re hauling your e-bike around often or focused on competitive performance where every pound counts, this added weight could be a real disadvantage.
Wheel Removal
Another disadvantage to having an IGH is that it tends to be a little harder to remove that rear tire, so if you get a flat or need to do some other repair, it’ll take a little more work than usual.
It generally entails disconnecting an extra cable or 2 and you might need a different wrench to get the tire loose.
Not a huge deal, but something to keep in mind.
Not as Efficient
This isn’t usually a big concern with e-bikes, but technically speaking, derailleurs tend to be a little more efficient at transferring the pedaling power to the rear wheel.
Some of this power is lost in translation with IGHs and, depending on the make and brand, can be as much as 15% or so (although most are likely in the 5 – 10% range).
Again, this loss of pedaling efficiency isn’t going to be a big deal for most recreational or transport riders, but again, folks looking for optimal performance might not like this.
Are They Worth Investing In?
This is of course a personal question, so there is no definitive answer I can provide, but I will share my 2 cents on the situation.
If you’re looking for a smooth acting e-bike and are planning on using it regularly for running errands or commuting to/from work, I could see investing in a bike with an IGH being worth it.
Especially if you’re already considering an e-bike with a mid-drive motor to begin with.
And now that Enviolo is offering more affordable IGHs, it’s allowing e-bike brands to include these upgraded technologies without drastic price increases.
As is the case with Ride1Up’s Prodigy V2, which comes with a mid-drive motor, an internal gear hub, and costs well under $3k.
An IGH is certainly an upgraded technology and if you’re looking for an enhanced riding experience, I think it’s worth the cost.
That said, I don’t think it’s the end-all-be-all of e-bikes either.
Rear hub motors and derailleurs work just fine, especially if you’re looking for a more passive riding experience where you don’t have to pedal as much.
Long-story-short, I do think IGHs are worth investing in, but it all depends on what you’re looking for.
Final Thoughts
Alrighty, that’ll about do it.
Internal gear hubs have actually been around for a long time, but it seems like they’re making a real comeback now that e-bikes are starting to use ’em.
IGHs are a great technology and they offer several advantages, but they have their downsides too – most notably their added weight and extra cost.
I don’t think I mentioned it earlier, but you also have to consider that if something does go wrong with an IGH, you’d likely have to send it back to the manufacturer for service.
Luckily, most are very reliable.
If you’re considering investing in an e-bike with an IGH, I would think about how you plan on using said bike before making a final decision, but luckily, the cost of this tech is coming down.
I hope you found this article helpful and if you have any extra comments or knowledge you’d like to share, please leave ’em below and I’ll get back to you shortly.
Happy riding.
