Pinion C1.12 Smartshift Gearbox Review: A Deep Dive
Overview
Since 2016, I’ve been riding and testing various bikes equipped with Pinion's cable-shifted gearboxes, experiencing firsthand their strengths and weaknesses. I wrote an article for Pinkbike in 2017 directly comparing two identical bikes with derailleur and gearbox setups.
Since then, many of the bikes I have bought or chosen to ride have had a gearbox, and despite them not being perfect, I never really want to go back. With the introduction of the Smartshift electric gearbox, Pinion has taken a significant step forward in shifting performance which was the main bugbear of the old system. Here are my thoughts after years on the different systems:
Gearbox Generalities
Pros:
Low unsprung weight
Minimal maintenance
Protected from external damage
Ability to pre-select gears when stationary or coasting
Very quiet
Cons:
Heavier overall weight (1.5-2 kg)
Limited ability to shift under load (historically)
Loss of drivetrain efficiency compared to derailleur systems
Limited availability of spare parts
Lower point of pickup engagement compared to some high-end hub + derailleur systems
Box fresh out the box.
Frame bag for storing the battery and cables.
Weight and Distribution
The total weight penalty of a Pinion gearbox-equipped bike is typically around 1.5-2 kg, depending on factors like frame design, chain length, and the specific drivetrain components being compared. The Smartshift adds an extra 250 grams compared to the cable-operated version for the battery and cables, plus you need to find somewhere to put those things, bike designers can incorporate this, when retro-fitting mine I found a small frame bag to wedge everything inside.
For perspective, if the average rider weighs 75 kg and their traditional enduro bike weighs 15.5 kg, adding a box may up it to 17 kg; nearly 10% more but the total system weight increase is only about 1.66%. However, the key difference lies in where that weight is positioned. By shifting weight from the rear wheel to the mainframe, the bike’s handling becomes noticeably more balanced. Removing unsprung weight from the rear (Shimano XT cassette+derailleur approx. 800g) significantly improves suspension performance and grip.
I’ve been vocal in the past about bike weight, and some people think I am anti-lightweight, which is not true. I think the weight is simply a result of the form and function of the bike, and you just need to deal with it. Yes, if someone could magically reduce the weight of my Tit-Ton-A-Tron from 19 kg to 9 kg with no performance change, I would take it. But the reality would be turning a confident and reliable MTB into something nervous and extremely delicate.
Durability and Maintenance
Ride a few years, then suck the old oil out…
…squeeze in some fresh, done! Oh, you’ll need to spend 3 seconds adding some fresh grease to those little gears too.
The real standout feature of Pinion gearboxes is their durability:
Failures: After at least 20,000 km of riding with Pinion gearboxes, I’ve only experienced one single mechanical failure—a complete loss of drive after a significant hit to the crank arm. While extremely rare, this highlights the importance of having a spare gearbox or service plan for quick replacements. My hope is that in the future local shops/friends will have spares to lend out or riders will own a spare. I can’t divulge the price (I buy my Pinions through a B2B account), but having a spare gearbox is going to be similar to a spare high-end shock, for example.
Oil Changes: Recommended oil changes are required after 10,000km. The process is really clean and takes just 3-4 minutes with a syringe to suck out the old oil and pump 60ml of fresh oil back in.
Bearings: I’ve never had to replace the bottom bracket bearings, even on my gravel bike with over 8,000 km of use, the system seems to be extremely well sealed from the elements.
Adjustments: Across all my Pinion-equipped bikes, I’ve never had to adjust cables, limit screws, straighten anything, or spend ages cleaning drivetrain gunk. With a belt drive, maintenance is virtually non-existent, and even with a chain setup, the single-speed chainline significantly reduces the wear and attention needed.
Shifting
The new trigger shifter is a great and much welcomed change.
Shifters: One of the main criticisms of Pinion gearboxes has been the grip shifter, this never bothered me too much personally. The only times I found it tough to change were in ‘race’ situations where you are standing and sprinting like a madman and trying to find a new gear.
The Smartshift trigger is a massive improvement over the previous version. While the touch required is exceptionally light, it can also lead to accidental clicks, but I have found the same on AXS systems, these usually occur when riding bumpy terrain and feeling for the lever. For my thumbs, the shift paddles are positioned closely together, occasionally pressing the wrong paddle during technical sections - I’m planning to cut the inside lever down soon for a bit more room. Using the app, the shift direction of these can be switched to your desire.
I hope future versions of the Smartshift system offer more adjustable trigger designs or alternative options. A Zirbel-style twist shifter, for example, would be great for a sleek look.Shifting: Like a normal derailleur, there is some skill involved with shifting. How you ease up on the power with the derailleur while allowing the chain to move across sprockets a similar technique is needed for the Pinion. While shifting up can be done under full load, shifting down with the grip shifter works best when climbing like this: wind up the tension on the shifter and you can feel it’s ready to change, wait until your cranks are at 11/5 ‘o’clock and bam, nice and easy change.
The Smartshift makes life easier but it’s still best practice to wait for the right time in the crank rotation, but can be done in other positions with electronically controlled timing: it measures power input and decides when it’s best to shift. However, it’s not a perfect solution if you simply expect flawless shifts 100% of the time while putting down full power.
Under Heavy Load: The system uses torque sensors to detect the power applied through the cranks. If the load is too high, the shift may be delayed or cancelled to avoid damaging the gearbox. When I deliberately forced down-shifts under heavy pedalling on the road, there were moments when it refused to shift. However, on the trail and with a little experience, this is never an issue.
Shift Speed: The speed of the shifting is incredible—each shift completes in approximately 150 milliseconds according to Pinion, making it feel almost instantaneous when you time it well. In comparison, some single shifts at a low-speed, with a big 51t cassette sprocket cassette could take a second or more, as the chain shifts at the bottom first and needs to rotate a long way before the actual change is finished at the top of the cassette.
Shifting without pedalling: one of the main advantages of the Pinion isn’t usually noticed when people test ride on for the first time after a lifetime of derailleur shifting where you can only change while pedalling (and one of the main reasons for chain breakages). With the box, you can change at any time, I’d estimate that now I make at least 50% of my shifts when I am not turning the cranks, this means that you are in the correct gear more often and don’t need to waste rotations getting into gear before you can put the power down. Bombing down a hill and seeing a climb coming up you can shift a couple in advance, coasting down and gaining speed you can shift up a few ready for when you need to. I’m sure a lot of DH racers who have shifted to Pinion for this season will find this a benefit at the World Cups.
Perceived Efficiency and Drivetrain Feel
One of the most debated aspects of gearboxes is their perceived loss of pedalling efficiency compared to traditional drivetrains:
Engagement Feel: Gearboxes have a "softer" feel when engaging power, lacking the direct mechanical connection of a chain between two sprockets. This does make them feel less responsive.
Bedding-in Period: A brand-new gearbox may feel stiffer and inefficient, but after a few hundred kilometres, the system beds in and becomes noticeably smoother. My gravel bike, which has done over 8,000 km feels more efficient now than when it was new, I don’t think anybody could say the same about a chain system after that much use!
Efficiency: It’s hard to find any scientific data, but the closest I could find is a test on CyclingAbout where they found a single-speed drive has a 97% efficiency, and the Pinion around 91%. We’d have to guess a derailleur system would be less than the SS setup as there are 2x derailleur pulleys to navigate and assuming the chain line is straight and everything is clean; a worn and muddy chain at an angle high up the cassette is going to be a lot lower.
Range: SRAM and their big birds of prey cassettes like to boast about a range of 520%. I’m not overly excited about massive ranges for the riding I do, but the 12speed Pinion towers above with a 600% range and doesn’t have a giant dinner plate at the rear wheel or a super long derailleur cage close to the ground and on the lookout for sticks and rocks.
Engagement: A Pinion bike essentially adds another freewheel to the existing rear hub. This means that the crank engagement is quite low, though this will be a benefit in some bike designs in the same way an OChain reduces chain tensions and improves suspension performance. An Onyx hub with instant engagement (or other low-engagement hubs) would speed things up for tech riding.
What Type of Riding is Best for Pinion?
On a scale of Road Bike —> DH Laps, I say the Pinion is an advantage after Trail. For road, XC racers and fast trail-focused riders, traditional derailleur setups may still hold the edge. It will be a little more efficient and responsive, risk of damage is lower, but you still need to deal with the maintenance.
For aggressive trail, enduro, and DH riders the Pinion will be the winner. You can bomb through anything without a care in the world, suspension and grip are improved and maintenance is low.
It also comes down to what kind of rider, how much you value pedalling efficiency and how much you like working on bikes. In my case, I have a gravel bike with a Pinion and wouldn’t change it for anything. It’s a bike I use for training and recovery rides, or popping to the shop. Yeah, it might be a fraction than a derailleur version but I don’t need any more bikes to maintain and I wouldn’t be looking for light weights at the gym if I wanted to get stronger.
Effigear: The Effigear system generally feels less efficient and more prone to friction than Pinion gearboxes, the upshifts on the Effigear under power are incredible, but downshifts require a complete pause in the crank rotation, the Pinion will change under some torque. I’ve had 2x Effigear bikes, one to test for PB which worked fine, and the Starling Spur I built a few years ago which broke within a week. The new owner hasn’t reported any further problems after the warranty replacement.
Effigear Mimic Gearbox: I haven’t tested the Mimic Gearbox yet, so I can’t comment on its relative performance. I believe it is essentially the same internals as the Effigear just with a concentric power output on the cranks axle instead of being at the top of the box and doubling as the main pivot axle. It’s named the Mimic as its mounting points ar the same as Pinion so could be used on a Pinion ready frame.
Final Thoughts
The Pinion C1.12 Smartshift gearbox represents a massive step forward in gearbox tech. For DH, park and enduro riders, I don’t think there are any more questions to be asked at this point, it’s a no-brainer. The only issue may be the cost, but I believe over a few years of riding, the Pinion will work out cheaper than most drivetrains, it will definitely cost less than the same mileage on a top-level SRAM AXS system.
For riders prioritising durability, minimal maintenance, and improved suspension performance due to lower unsprung weight, the Smartshift system is going to make a significant dent in the derailleur market.
Great free article! But, how do I win it and support AstonMTB?
Head to my Raffall page and check out my latest Competitions. Here you can win some amazing bikes and products. Choose your tickets, answer a simple question and you have an extremely good chance to win.
Global shipping is also included so entrants are invited from anywhere in the world.
The giveaway is guaranteed to happen on the end date regardless of how many tickets are sold. No extensions, no minimum ticket sales.
These competitions fund my reviews which I believe are the only truly independent MTB reviews online. All of the prizes and all of the products you see are bought by me - no sponsored posts, no freebies and no back-handers.
Alternatively, donate below. Thanks, Paul.