Table of Contents
- 3×3 Nine Gear Hub
- Revolute Hub1
- Pinion Smart Shift Gearboxes
- Intradrive Gearbox Powertrain
- Classified Powershift Gear Hubs
- Summary
New bicycle gearboxes are coming onto the market quicker than at any time in history.
Until recently, Rohloff was the only gear hub option that you needed to know about. Some Rohloff customers have ridden more than 430,000km on their hubs, which is a testament to the excellent engineering behind the product.
Pinion later came along and offered even wider gear ranges and smaller gear steps with their reliable crank gearboxes. And in recent years, we’re seeing more premium brands such as Kindernay offering lightweight, robust and efficient gear hubs, and Effigear, which have not one but two gearboxes in their product range.
The next wave of gearboxes is currently being developed around e-Bike use, and what you’ll see today is only the tip of the iceberg.
Mid-drive e-Bike motors put a lot of strain on derailleur drivetrains, resulting in faster component wear. As a result, you can expect to see many more low-maintenance, hassle-free, and robust gearboxes coming soon.
Let’s take a closer look at the latest offerings.
3×3 Nine Gear Hub
3×3 is a new brand by engineering company HB-Hightech, and their first bike product is a nine-speed internal gear hub.
Alright, here are the numbers on this German-built gearbox. It offers a 554% gear range, which is wider than both the Rohloff (526%) and Kindernay hubs (543%). This means that when we peg the lowest gears of all of these hubs, you’ll have the ability to ride at a slightly higher speed with the 3×3 hub.
However, there are fewer gears across this gear range, resulting in gear steps of a rather large 23.76%. This is almost twice as much as Rohloff (13.6%) or Kindernay (13.9%), so it’s clear that 3×3 is targetting the electric bike market with their hub. As e-Bikes accelerate faster, it’s not uncommon to find yourself changing 2 or 3 gears at once. The larger gear steps solve this problem but make the hub less suitable for regular bikes.
The 3×3 hub is around 2kg/4.4lb, which is a touch heavier than both Rohloff and Kindernay. But the hub is also rated for 250Nm input torque, which is significantly higher than both of those (130 and 160Nm, respectively). That means you can run a very powerful mid-drive motor if you like.
Interestingly, the hub is lubricated with grease instead of oil.
Why did 3×3 choose grease? They are hoping their hub doesn’t need any maintenance for 25,000km. That’s five times further than Rohloff recommended for their routine oil changes. I should note that greasing the 3×3 hub will be more labour intensive than the simple oil changes of the Rohloff, but it’s nice that it doesn’t need to be tinkered with as often.
Those who have read my Alfine hub resource know that if internal gear hubs are not grease-packed appropriately for wet environments – water can and will work its way into the hub shell. This is one of the downsides of grease lubrication, so let’s hope the 3×3 hubs are well-sealed from the factory.
Additionally, grease is a bit less fluid than oil in the sub-zero temperature parts of the world, which can result in gears sticking and a reduced drive efficiency too. Hopefully, 3×3 choose suitable grease for the coldest regions.
There is an electronic shifter available that’s wirelessly controlled. This can connect to an internal battery in the frame or directly to an e-Bike’s power supply. Alternatively, a twist shifter can be used, which looks to fit on both drop bars and flat bars.
The hub will fit both quick release frames or those with 142/148mm thru-axles. You’ll find the 3×3 hubs fitted to a range of bikes next year and will later be able to order one separately.
Revolute Hub1
Another cool German-made gear hub that’s coming soon is the Reevoluteh Hub1. This is a six-speed hub with a gear range of 400%, resulting in gear steps of over 30%, making it best suited to e-Bikes.
This hub has a few unique features.
Revolute says that the Hub1 is the only gear hub that allows you to shift properly under a load. It’s also the only hub that uses helical gears, although the Shimano Alfine 11-speed uses a mix of helical and spur gears.
The advantage of helical gears is that they are especially quiet. This is because angled gears distribute pressure gradually along the whole tooth, and this gradual engagement allows them to engage much more smoothly and silently. In comparison, spur gear teeth contact straight away and hold together for a longer period of time.
So, why don’t all gear hubs use smooth and silent helical gears?
It’s mostly because they are a bit less efficient. As the gears mesh, they also push apart from each other (axial thrust), which generates an increase in friction (heat). The difference in efficiency isn’t huge, but internal gear hubs are already less efficient than derailleurs, so every little bit counts…
…. until now. With batteries and motors, we can easily mask the slight efficiency loss here. That’s why noticeably less efficient CVT hubs like the Enviolo are popular on e-Bikes, but a bit of a drag on regular bikes.
Another interesting feature of the Revolute hub is that it doesn’t spin backwards! This means that when you stop on a hill, you do not need to pull your brakes to prevent the bike from rolling backwards. This will be especially handy with heavily-laden cargo bikes but would be nice on a regular bike too.
In terms of bike manoeuvrability, you’d think a one-direction hub is impractical. Well, Revolute has gone and added a neutral gear. You can access neutral by pushing the safety button on the shifter and downshifting beyond the first gear.
As the rear hub doesn’t spin backwards, it’s a requirement to have a freewheel at the crankset to move your pedals backwards – that’s whether you use an e-Bike or not.
Like the 3×3 hub, the Revolute will handle a monstrous 250Nm of torque, making it ideal for almost any mid-drive e-Bike. The hub is around 2kg as a result, which is on the heavy side for a 6-speed. Consider that the Kindernay 7-speed is 40% lighter in comparison.
Unlike the 3×3 hub, the Revolute runs on a more common oil lubrication system. The oil change intervals are 5000km like most similar hub designs.
The Revolute uses standard six-bolt rotors and even the 9-spline cogs from a HG cassette body. The straight pull spoke design looks cool but makes spoke replacement a bit easier too. It’s available for quick release or thru-axles, and the price will be around 1200 Euros.
Pinion Smart Shift Gearboxes
Pinion has been producing 6, 9, 12 and 18 speed gearboxes for over a decade now, but has only just got around to introducing electronic shifting. This new electronic trigger shifter is unfortunately not backwards-compatible for current Pinion gearbox owners and is only available for e-Bikes.
The Smart Shift gearboxes are actually an all-new product for Pinion. They are internally different to the existing P and C-line gearboxes as they require a different shifting mechanism and various sensors. But they are based on the lighter and narrower C-line gearboxes. There will be 6, 9 and 12-speed versions.
The new shifter offers lightning-fast shifting speeds and a lighter shifting action too. It has a grippy rubberised button surface for your thumb and haptic buttons so you know precisely when you’ve made your shift. Additionally, you can customise the buttons to shift how you like. The inbuilt gearbox sensors then allow you to know your gear indication on the LED display.
There is an automatic start gear feature that allows you to choose a desired gear that is automatically engaged when the bike is stationary. This means that you’ll always have the perfect take-off gear.
With this level of tech, I think we can assume that automatic gear shifting is likely in the works.
Intradrive Gearbox Powertrain
Intradrive is a Scottish company that has been working for six years full-time on an integrated gearbox and motor unit.
Their prototype gearbox offers eight gears across a 430% gear range, resulting in gear steps of around 23%. This is essentially the same gear range and gear steps as a SRAM Ex1 derailleur drivetrain, however, the main difference is that the large spur gears are protected from the elements inside a sealed oil bath enclosure.
One of the coolest things about this British-built drive unit is that it can be attached to any bike built for Shimano EP8 motors. Even the 630Wh Intradrive battery will be developed to fit the Shimano battery mounting points. This means that bike manufacturers can fit the full powertrain to existing bike models, and current Shimano EP8 users can easily make the switch too.
One of the biggest advantages of this system is that it will wear through fewer drivetrain components. It will also reduce the unsprung mass at the rear wheel of full suspension bikes, improving the weight distribution and suspension performance compared to derailleurs, but even more so when compared to the internal gear hubs I’ve previously discussed.
The motor will offer upwards of 75Nm of torque, which is lower than similar integrated motor/gearbox systems but keep in mind that this gearbox is pitched towards mountain bikes, rather than cargo bikes.
The shifting will be electronic, with the potential to run the gearbox and motor using automatic shifting.
With Intradrive showing that an integrated gearbox and motor can fit onto standard frame mounts – I’d like to predict that we will see something similar from Pinion in the coming years. After all, Valeo and Effigear have been testing their motor for a few years now.
Classified Powershift Gear Hubs
I’ve been looking for an excuse to talk about Classified hubs for a little while, and I think now is my time.
These planetary hubs are a two-speed design and offer the same functionality as a front derailleur. If you fit a 48-tooth chainring up front, you get an effective 33-tooth chainring when using the reduction gear in the hub.
Classified hubs were originally released with complete gravel bikes a year ago, then as complete carbon wheelsets from the company itself. Now, Classified has partnered with Enve, DT Swiss, Mavic and more wheel brands to make their hub more accessible.
The hub uses a thru-axle design and it’s the axle that receives the wireless signal to shift. Classified says that the efficiency in the reduction gear is very high (99%), you can make shifts at 1000-watts power output, and the shifts are almost instantaneous – faster than any front derailleur.
The reason these hubs are great is that you get the simplicity and range of a 1X drivetrain but without the large gear steps of a wide-range cassette. This means you can stay closer to your preferred pedal cadence at a broad range of speeds.
Classified drivetrains also ditch the incredibly inefficient 9 and 10 tooth cogs that are typically found on 1X cassettes, and are designed around larger and more efficient front chainrings too.
I’m actually excited most about the soon-to-be-released MTB version, allowing off-road riders who ride on flatter terrain to fit smaller cassettes (ie. 11-40t) instead of the ubiquitous 10-52t models currently on offer.
Summary
I hope these new gearboxes got you a little bit more excited about this quickly evolving drivetrain tech.
Let me know in the comments if you come across any prototype gearbox drivetrains in development, as it would be great to analyse their designs in future articles.
FAQs
What is a pinion gearbox bike? ›
Modeled after proven automobile transmission technology, Pinion Gearboxes use spur gearing with two sub-units connected in sequence. The individual gear ratios are derived by matching the two sub-units with various cog pairings.
Where is the gearbox on a bike? ›Instead, a gearbox is integrated directly into the frame, with the weight positioned centrally on the bike. The cranks drive the gears directly and the output is converted in the gearbox and then transmitted to the back wheel via a chain.
What is a drivetrain on a bike? ›The 'drivetrain' of the bike consists of all the bits that you use to push (or pull) the bike along. The key components are the pedals, cranks, chainrings, chain, cogs (cassette) and derailleur.
How does a pinion gearbox work? ›In Pinion gearboxes, power is transmitted through only two sets of cogs. This results in consistently high efficiency, minimal noise and a direct, lossless feeling at the pedals. The redundant gears and increased chain wear of other drivetrains simply do not apply to Pinion gearboxes.
Which pinion gear is faster? ›A larger pinion gear or a smaller spur gear will both provide more speed. A smaller pinion gear or a larger spur gear will provide more torque and acceleration, but less top speed. You may change one or both gears to achieve the desired effect.
What are the different types of gearbox used in bikes? ›Gears: Motorcycle transmissions have three gear types — fixed, freewheeling and slider.
Which gear is the pinion gear? ›Generally, when meshing pair of gears, the smaller gear is called a pinion gear. Also, it refers to the cylindrical gear that meshes with a rack in a rack-and-pinion mechanism which transforms rotational motion to linear motion.
How do I check my gearbox? ›- Check for gearbox fluid leakage. ...
- Check dashboard warning lights. ...
- Gears become unresponsive. ...
- Listen for any unusual sounds. ...
- Beware a shake, jerk or grind. ...
- There might be a rumbling in neutral.
Low Gear = Easy = Good for Climbing: The “low” gear on your bike is the smallest chain ring in the front and the largest cog on your cassette (rear gears). In this position, the pedaling will be the easiest and you'll be able to pedal uphill with the smallest amount of resistance.
What are the three types of drivetrain? ›The most common types of drivetrains are front-wheel drive (FWD), rear-wheel drive (RWD), four-wheel drive (4WD) and all-wheel drive (AWD).
Is it OK to use wd40 on bike chain? ›
In summary, WD-40 is great for cleaning and degreasing your chain, but doesn't work well as a lubricant. It will provide some small amount of lubrication, but nowhere near enough for your bike chain to run smoothly. It's best to use a high-quality, bike-specific lubricant instead.
Is pinion gear same as gear? ›The larger of the meshing pair is called the gear and smaller is called the pinion.
Is pinion gear input or output? ›If the pinion gear is attached to the driven shaft (i.e., output), then the output speed increases. This result is referred to as gearing up. On the other hand, if the pinion gear is attached to the driving shaft (i.e., the input), then the output speed decreases.
What is a gear ratio for dummies? ›How do you calculate gear ratio? You just count the number of teeth in the two gears and divide. So if one gear has 60 teeth and another has 20, the gear ratio when these two gears are connected together is 3:1.
What is the formula for the gear ratio? ›Students derive the formula for finding the gear ratio of a pair of gears: gear ratio = teeth in driven gear/teeth in driver gear.
What gear ratio gives the most speed? ›A lower (taller) gear ratio provides a higher top speed, and a higher (shorter) gear ratio provides faster acceleration. . Besides the gears in the transmission, there is also a gear in the rear differential.
Is a bigger or smaller pinion gear better for speed? ›A bigger pinion or smaller spur gear makes the vehicle have more top speed, at a decrease in acceleration. It's most likely that gearing up will make everything run a bit hotter, and shorten run times. A smaller pinion or larger spur gear has the opposite effect.
What gear is best for speed? ›The gears determine the amount of power available from the engine. First gear provides the most pulling power but the least potential for speed, whilst fifth gear which provides the least pulling power allows the greatest range of speed.
What are 3 types of gearboxes? ›In general, there are three different types of gearboxes: concentric, parallel, and right angle.
Which type of gearbox is best? ›Torque converters are the oldest form of automatic transmission. Because of this, it is the most reliable automatic gearbox. It uses a planetary system for gears with an impeller and turbine.
What is an example of a pinion gear? ›
A perfect example of rack gears and pinion gear systems is the steering system on many cars. The driver turns the steering wheel which rotates the gear, which then engages the rack, so as the gear turns it slides the rack to the right or the left depending on which way the steering wheel is turned.
What are the advantages of pinion gear? ›Rack and Pinion - known for their long strokes, rack and pinion drive systems virtually have no limit on travel length as long as the rack can be made long enough. The max travel length is instead limited by its support structure. By using a rack instead of a belt, elasticity is eliminated, and rigidity is increased.
How many types of pinion are there? ›Pinions can be either spur or helical type gears, and be either the driving or driven gear, depending on the application.
What are the common faults in gearbox? ›- Insufficient Acceleration or Throttle Response. ...
- Transmission Fluid Spillage Under Your Car. ...
- Grinding Noise and Buzzing During the Gear Shifts. ...
- Difficulty in Gear Shifting. ...
- Gears Slipping. ...
- Burning Smell. ...
- Congested Filter.
For flat places, a ratio of 2.6 to 3.0 is ideal for most people. The lower value of this range, with a cadence of 90 rpm, will allow us to ride around 30km/h, while the upper, 34km/h. If you're just starting out on your adventure on a single speed or fixed gear bike, a gear ratio of around 2.7-2.8 will be ideal.
What is the best gear for cycling? ›- Helmets.
- Budget Bike Helmets.
- Road Bike Helmets.
- Mountain Bike Helmets.
- Downhill Helmets.
- Bike Racks, Locks, and Pumps.
- Bike Racks.
- Bike Locks.
There are four different types of drivetrains: all-wheel drive, four-wheel drive, front-wheel drive, and rear-wheel drive.
What is the most popular drivetrain? ›Front-wheel drive – or FWD – is by far the most common drivetrain. This layout connects your engine to your front wheels, with the rear wheels rotating freely.
Which drivetrain is best? ›Rear-Wheel Drive (RWD)
Because the weight is more evenly distributed with a RWD drivetrain, they tend to provide better handling, although not in slippery conditions. RWD systems also offer high towing and payload capacities, which is why they're so often found in high-end pick-up trucks.
When you buy a bike, the original chain comes greased which, if maintained, ensures longevity. However, some of the lubricant options will actually degrade the lubricants. So, aside from brand bike chain lube, the most common options people opt for include olive oil, household greases, and cooking oil.
How often should I oil my bike chain? ›
When should you lube your bike chain? Normally every 100-150 miles or once a week if you are riding most days on pavement in dry conditions. If you are riding mostly in dry conditions on pavement, you probably don't need to clean your chain every time you lube it.
Can I use chainsaw oil on my bike chain? ›Can I use chainsaw oil on my bike chain? Yes. You can use chainsaw (bar) oil as a wet bike chain lube and would be best used for riding in inclement weather where you need a sticky oil that will not get washed off from rain or wet conditions.
How do I get the right pinion angle? ›Changing the angle is as simple as adding wedged shims between the rear axle housing and the springs to slightly rotate the housing upward or downward. Putting the thick end of the wedge to the rear lowers the pinion; putting the thick edge to the front raises the pinion.
Can you shift a pinion gearbox under load? ›While it's not best practice to shift under load on any drivetrain, a derailleur has a much higher tolerance for it. There is a technique to shifting with a Pinion gearbox where you'll need to back off on your power for a split second to make the shift.
Does the pinion gear drive? ›gears. …of a gear pair (the pinion) is on the driving shaft, the pair acts to reduce speed and to amplify torque; if the pinion is on the driven shaft the pair acts as a speed increaser and a torque reducer.
Which is bigger pinion or gear? ›The ring gear diameter is generally constant for any particular differential design regardless of the ratio. This means that the pinion size changes with the ratio and for lower gears (higher numerically) the pinion teeth are smaller.
Why pinion is made harder than gear? ›Making Pinion Harder than Gear to Equalize Wear
The harder pinion teeth correct the errors in the gear teeth to some extent by the initial wear and then seem to burnish the teeth of the gear and increase its ability to withstand wear by the greater hardness due to the cold-working of the surface.
The ratio is the number of teeth on the driven gear (ring) divided by the number of teeth on the drive gear (pinion). So, if the ring gear has 37 teeth and the pinion has 9 teeth, the ratio is 4.11:1. That also means that for every one turn of the ring gear, the pinion will turn 4.11 times.
What is the input and output of bicycle gear system? ›Input and Output
On a bicycle, the pedals are the input component. The output component of a machine is the last part that moves. Bicycle pedals make the rear wheel move. The rear wheel is the output component.
The gear ratio is calculated by dividing the output speed by the input speed (i= Ws/ We) or by dividing the number of teeth of the driving gear by the number of teeth of the driven gear (i= Ze/ Zs).
How is a pinion gear different from a regular gear? ›
When pinion is the driver, it results in step down drive in which the output speed decreases and the torque increases. On the other hand, when the gear is the driver, it results in step up drive in which the output speed increases and the torque decreases.
What is a pinion vs spur gear? ›Summary. The pinion gear on your RC car is the gear that is attached to your motor, and the spur gear is the gear that the pinion drives. The spur is sometimes integrated with a slipper clutch or with a differential in the case of a 4WD car.
How efficient is the pinion gearbox? ›The 12 gears of the Pinion P and C1. 12 deliver a massive 600% gear range. Compared to the 526% gear range in a Rohloff Speedhub, the 520% range of the SRAM Eagle 1×12, 491% from a 2×10 (36/24 chainset/11-36t cassette), and the average 435% range of a 1×11 setup, the C1.
Is a bigger pinion gear faster? ›A bigger pinion or smaller spur gear makes the vehicle have more top speed, at a decrease in acceleration. It's most likely that gearing up will make everything run a bit hotter, and shorten run times. A smaller pinion or larger spur gear has the opposite effect.
Is a high pinion or low pinion stronger? ›It's common knowledge that a high-pinion front axle is stronger than its low-pinion equivalent, but not everyone understands why. A low-pinion axle positions the pinion below the centerline of the axle, while a high-pinion axle places the pinion above the centerline of the axle.
Is rack and pinion better? ›Steering gear boxes typically have more components, which makes them heavier. They're also more difficult to handle. If you want a steering system that's durable, straightforward, and lightweight, rack and pinion is the way to go. You'll get better handling and fuel economy.
What is the advantage of rack and pinion over gearbox? ›Hemmings also notes that the rack and pinion steering system weighs less than a recirculating ball gearbox, which helps improve gas mileage. Rack and pinion systems are lighter because they don't require the idler arms, Pitman arms, center links, and tie rod sleeves found in conventional steering systems.
What are the types of gear and pinion? ›Pinions can be either spur or helical type gears, and be either the driving or driven gear, depending on the application. Pinion gears are used in many different types of gearing systems such as ring and pinion or rack and pinion systems. Pump Gear – A pump gear is the name for a gear used in gear pumps.
What are the 4 types of gears? ›- Spur Gear. Spur gears transmit power through shafts that are parallel. ...
- Helical Gear. ...
- Double Helical Gear. ...
- Herringbone Gear. ...
- Bevel Gear. ...
- Worm Gear. ...
- Hypoid Gear.
Helical gears are more durable than spur gears because the load gets distributed across more teeth. Hence, for a given load, the force will be spread out better than with a spur gear, resulting in less wear on individual teeth.
What are the three types of spur gears? ›
There are three main classes of spur gears: external tooth, internal tooth, and rack-and-pinion.
Which bike gear is the fastest? ›High Gear = Hard = Good for Descending: The “highest” gear on your bike is the largest chain ring in the front and the smallest cog on your cassette (rear gears). In this position, the pedaling will be the hardest and you'll be able to accelerate while traveling downhill.
What is the most efficient gearbox? ›Planetary, inline helical and bevel helical gearboxes are the most efficient, whereas worm gearboxes are usually the least efficient.
Can a rack and pinion increase speed? ›Rack-and-pinion drives accelerate loads faster than ball screws and can maintain higher speeds than them. Rack-and-pinion drives are also stiffer, for better accuracy, and that stiffness remains more consistent than that of ball screws.