Pinion Smart.Shift Review: Imperfect Perfection – John Watson | The Radavist | A group of individuals who share a love of cycling and the outdoors.

The Pinion Smart.Shift gearbox offers electronic shifting for instantaneous engagement, eliminating the soft or sluggish feeling found with the grip shift Pinion systems. Yet this system isn’t as perfect as it’s marketed, and John found one critical shortcoming during his review period…

When a new piece of technology comes out, I find it often hard to believe the marketing hype. As Travis found with the SRAM Maven brakes, products often have flaws, but that doesn’t take away from their overall merit, and pointing these flaws out constructively and contextually is simply part of the job.

Nothing is perfect, yet the imperfect perfection of Pinion’s new electronic shifting Smart.Shift gearbox – this is not an Ebike motor – won me over in all ways but one. But before we get into that, let’s look at how these systems work.

Pinion Smart.Shift Quick Hits

Model reviewed: Pinion C1.12i
Weight: 2,350 grams
Price: $2,779 for gearbox, TE-1 shifter, and cranks. Sprockets and belts are sold separately.
Gear rack: 12 shifting points
20,000 shifts per 100% battery charge
Gearing jump percentage is +/- 17%
Chainline: 50 mm
Q Factor: 168 mm
Gearing spread: 600%
Max. Torque: 250 Nm
Temperature Range: -15° C to +40° C or 5º F to 104º F
Service Interval: Every 10,000 km (the new gearboxes don’t require once a year like the old ones)

How Does the Pinion Gearbox Work?

Much like a transmission found in a car, Pinion gearboxes use spur gearing with two sub-units along an axle path. There are two groups, or sub-units, within the box. The C1.12i (i denotes electronic shifting) gearbox is built using a 4-gear unit mated to a 3-gear unit – a 4×3 gearing setup. The individual gear ratios are derived by matching the two sub-units with various cog pairings. The Smart.Shift is also available in a C1.9i configuration.

It sounds complicated, but it’s a very simple mechanical system. Check out the above video for a simplified look. There are two methods for shifting: mechanical and electronic. If the gearbox is mechanical, shifting gears comes from a grip shift mounted on the handlebar next to a shortened handlebar grip. Or if it’s electronic, like the Smart.Shift, comes in via an electronic signal fired by either a trigger shifter dubbed the Pinion TE-1, or a TRP drop bar lever called the Hywire.

Pinion packs these spur gears into a dust and water-proof housing (even submersion!) made from aluminum (original P-Line and not compatible with Smart.Shift) or magnesium (the new C-Line Smart.Shift), and the entire assemblage is made in Germany.

Vessel for Testing

Over the course of a few months, I rode the Viral Bikes Derive hardtail 29er, which is built around the Pinion Smart.Shift system. Throughout my review period, I primarily rode the bike on our local terrain here in Santa Fe from piñon and juniper forests in the foothills well up into the aspen, spruce, and ponderosa forests at higher elevations. The trails ranged from hardpack and loose to rugged and rough rocky terrain high up into the mountain. Where the bike “came alive,” however, was on a few overnighters once it was loaded down. My review of the Derive is dropping tomorrow, so check back then for more!

I’m going to tackle the Smart.Shift C1.12i review in a different manner, addressing some common questions I had during the review process and ones I received from friends.

Any Maintenance?

Pinion recommends you change the gearbox oil every 10,000 kilometers. Other than that, the system is virtually maintenance-free. There is a slight break-in period as the gear oil coats the gearbox evenly. It does get noticeably smoother as you load on the miles.

Gearing Choices?

The C1.12i gearbox is built using a 4-gear unit mated to a 3-gear unit of which, the 12 speeds are derived. The “front chainring” and “sprockets/cogs” supplied with the Derive was 32 t x 34 t. Gates makes CDX chainrings and sprockets in various sizes to accommodate your gearing needs.

Every (Gear) Inch Counts

To compare a SRAM Eagle cassette to the Pinion C1.12i, you take the maximum number of teeth on the largest cassette sprocket, divide it by the smallest cog, and multiply by 100. (52 ÷ 10 = 5.2 x 100 = 520%). I run a 28-tooth chainring on my touring bikes with a 29 x 2.6″ (or 3″) tire and a 10-52t Eagle cassette, which gives me 16 gear inches at 28t x 52t.

The same calculator gives me 17.6 gear inches with the C1.12i gearing spread (600%) and a 32 t x 34 t chainring/sprocket. The gear inch gain is easier to gap with the C1.12i. Add a larger rear cog or a smaller front cog to dial in the gearing spread. Any Pinion dealer or Pinion-equipped bike company can walk you through this.

The equivalent gearing the C1.12i provides would be something like a 10-60 cassette 32t chainring

If the combination of chainring cog or rear cog feels overwhelming, I asked Steve from Viral Bikes about how he chooses Pinion system gearing, and his reply was comforting:

“When people want either a lower or higher gear spread, I’ll spec the cogs and build accordingly. If they want a lot of gearing for touring, or if they want a faster-paced gearing spread, it’s easy to accommodate that…”

Can You Use Your Favorite Hubs?

Depending on your frame’s rear spacing and whether you can achieve the 50 mm chain line required for the Pinion system, you can roll with your favorite hubs. Viral supplied these tasty purple Industry Nine wheels for my review bike.

Weight Distribution

Versus a bike with a rear derailleur or even a Rohloff hub, the weight on a Pinion gearbox-equipped bike is at the bottom bracket, lower than the hub centerline, and thus, the bike behaves very differently, especially with a suspension fork. The center of gravity is lower and we’ll get into that more tomorrow, but spoiler alert: it’s amazing. Bikes with a Pinion really know how to plow!

How Important is the Belt Tension?

Gates makes belts for automobiles running the gamut from engine timing to serpentine, and in cars, there is always an idler pulley to retain the appropriate tension in the system. The Smart.Shift has no such idler pulley with a hardtail – full suspension bikes do use an idler pulley – so tension is relayed by sliding dropouts, eccentric bottom bracket, rocker dropouts, or other adjustable dropout systems.

Belt tension is checked by the Krikit tension gauge, or if you don’t have one of those (who does?!), use the free Gates iPhone app. The stiffer the frame’s rear triangle, the “slacker” the “span tension” can be. More on that tomorrow…

Can Smart.Shift Be Used With a Chain?

Yes. While the Smart.Shift is optimized for a Gates belt drive system, you can totally run a chain and a singlespeed rear cog if you’re belt averse. Chains are more readily available and easily repairable/breakable. A chain would also eliminate the need to have a break in your frame.

If you’re into belts and touring in remote areas, it’s best practice to carry a spare belt in its original packaging. If you need to store it without the packaging, follow Gates’ belt handling pointers for coiling belts.

If you improperly handle a belt, it can drastically shorten its lifespan. A healthy belt can last upwards of 30,000 km or 19,000 miles. So, if you’re conscious, you might want to swap on a new belt roughly every two gearbox oil service intervals.

Belts won’t rust, won’t require any lube, are quiet, and offer lower-friction riding experiences when the tension is properly adjusted.

Pinion-equipped Gates belt frames need to be able to open the rear triangle to pass the belt into the driveline. The Derive has a bolt above the dropout. While it is possible to retrofit some metal frames, we’ll go into why this isn’t always possible tomorrow…

Which CDX Cogs Did I Use?

The Smart.Shift can be paired with various Gates CDX cogs, depending on the application. My review bike Viral Derive came with 32 t x 34 t cogs. And since I wanted to ride a bigger tire, Steve opted for a longer belt since the dropouts are further back to accommodate the clearance at the chainstays. This also lengthens the wheelbase slightly.

Shifting While Standing Still

One of my favorite features of the Smart.Shift system is the ability to shift up and down the 12-gear spread while at a standstill. This is possible because the cranks are not engaged with the shifting mechanism or belt drive gear. You can spin the cranks backward without the freehub moving. Neat!

Ugh, Apps!

I don’t want to pair my bicycle with an app. Ever. It feels like this is becoming more and more common. The Smart.Shift system only requires the phone app if you want to enable two of its “features.” The first is Smart.Select which allows you to select your starting gear. The second is Pre.Select, which allows the Smart.Shift system to automatically select a gear based on your speed. Both of these seem to be marketed to Ebikes. You can also use the app to switch the button configuration on the TE-1 flat bar e-trigger or TRP Hywire drop bar shifters.

Smart.Select and Pre.Select requires a speed sensor to be installed, and in the case of Viral Bikes, Steve does not spec this sensor as it’s unnecessarily complicated.

Unfortunately, with the case of the Derive hardtail, the only way to determine your gearing is to check the app – Pinion makes a gear display but currently, Viral Bikes does not spec it – and if you’re using another Bluetooth device like headphones, you cannot run both at the same time.

Once I connected the app, I updated the firmware because that’s a thing we have to do now with bikes.

Battery Life?

Before heading out on an overnighter, I connected the app and found that after a few months of riding, the battery had only drained 3% from its fresh charge upon receiving the bike. Not bad. Even after riding for ten hours on our overnighter, the power showed no loss.

The battery is hidden in the frame of the Derive and can be removed/replaced in the event of failure. It takes three hours to charge the battery with the supplied charger via this port.

What About the Weight?

Bicycle weight, particularly when most of it is as low as possible on the frame, is negligible for the riding experience gained from a Smart.Shift system. The tradeoffs for added weight are immense: relatively low and simple maintenance, increased ground clearance (since there’s no rear derailleur), added shred factor (more on that tomorrow), and very low gear inches.

Shifting Feel

In my limited experience with mechanical Pinion systems and Rohloff hubs, the shifting always feels sluggish or soft. And with the mechanical Pinion gearboxes, you literally had to back off from pedaling to shift. The Smart.Shift eliminates that with near instantaneous shifting, akin to SRAM AXS or Di2. Pinion claims this to be 0.5 seconds.

What is noticeable is the +/- 17% step between gears that feel consistent versus derailleur systems like Eagle, where the steps are more apparent.

For those curious, the Smart.Shift system felt similar to the Classified hub system I reviewed earlier this year, but the Classified hub actually shifted under load…

Riding Experiences (The Big One)

Ok, hold onto yer butts…

Achilles Number One (Big)

Unfortunately, as much as people want to crown the Smart.Shift system as the “fix” to the spongy and sluggish feel of the grip shift-actuated mechanical Pinion systems and their inability to shift under slight load, it has a fatal flaw. When the Smart.Shift was announced, it lauded the ability to “shift under load,” addressing the number one drawback to the mechanical Pinion system.

Even automobile transmissions struggle with shifting while the system is under load, often due to excessive torque provided by the car’s engine. So it threw me some big alarm bells when I saw all the marketing – and every other review, I might add – saying the Smart.Shift gearbox shifts perfectly under load.

I brushed it off, knowing I’d potentially never get to actually ride one. Then Steve from Viral contacted me, asking if I wanted to try out the Derive hardtail…

The first few rides, I was very impressed with the Smart.Shift system. Its gear spread was more than adequate for trail riding with plenty left over for touring and bike camping; the 600% gearing was superb! On my favorite lunch loop in the foothills here, I was able to shift throughout the gearing spread under all conditions, charging down familiar descents and up climbs with ease.

I felt like the Smart.Shift was indeed a derailleur-killer. Wow!

Then I went on a group ride into our backcountry, where several of the trails are steep and abrupt, forcing you to dump gears after chomping down chunky terrain and grinding up long, bench-cut, off-camber trails.

It was on one particular gut-punch trail that the system misfired multiple times. Then on another trail, less steep but equally as abrupt, it misfired again — all while I was pedaling seated. If I were out of the saddle, it’d shift just fine. But when I was seated, perched on the nose of the saddle, and spinning up a grade, it wouldn’t budge.

If I got out of the saddle and shifted, it’d engage, oftentimes making a loud “pop” – the manual for Smart.Shift says the loud, metallic “popping” is normal:

“Shifting under load may be associated with a popping noise. This is not a cause for concern. The system is designed for shifting under full load and is not damaged.”

What I found was the problem centered around torque. If I were in a spinny gear and went to downshift into an even spinnier gear while seated, even after “backing off” on my pedal stroke before the cranks reached 12/6, or Top Dead Center – the point at which shifting engages – due to a magnet mounted to the crankarm, the system would not shift. This is because TDC is relative to the perpendicular plane the bike is on. So, if you’re on a 14% grade, TDC adjusts perpendicular to that plane.

This explains why, in some cases, I could get out of the saddle and it would shift. In moving my body to the front of the bike, the TDC experienced less load.

Pinion states the maximum load is 250 Nm.

Feeling frustrated after the first ride with these issues, I flipped through the Pinion Smart Shift manual. Amidst all the claims of it “shifting under load,” the manual states:

“In certain situations, a gear shift may be canceled due to excessive load to protect the Smart.Shift system from damage.”

I found for my size/torque output, I’d have to be in gear #4 – with #1 being the spinniest and #12 being the hardest to push – in order to shift while climbing. To fix this, I simply compensated my riding style, being more mindful to dump gears before engaging up a steep climb.

This is similar to an automatic transmission used in off-road scenarios with high torque-output systems like diesel engines. That’s why diesels come with torque converters mounted between the automatic transmission and the engine. These converters lessen the torque on the automatic transmission gearbox, extending its lifespan. Regarding the Smart.Shift system, the ECU controlling the shifting acts sort of like a torque converter, sensing the 250 Nm and halting the shift if it breaches that number.

But I am not a diesel-powered torque factory. I’m 190 lbs, 6′-2″ human, with long legs and mediocre climbing prowess. Although looking at my Strava data, on some climbs, I’ve produced upwards of 400 watts (estimated) for over three minutes. So maybe I was throwing down too many watts?

I contacted Steve from Viral Bikes to talk about the Derive hardtail and Pinion Smart.Shift. We had a discussion that led us to determine that the 175 mm cranks and my long legs could potentially be overloading the system and hitting the 250 Nm load wall. Steve stated:

“The size small bikes are specced with 165 mm cranks, medium and large with 170 mm cranks. You’re on the only XL bike in circulation right now. It has 175 mm cranks, and to be honest, that could very well be why you’re hitting the load wall so easily. I’ve never experienced the problem you’re encountering, nor have I heard of it happening.”

I’ve been told, anecdotally, by product managers and engineers in the bike industry that this is also why Ebikes are usually specced with 165 mm cranks. 175 mm cranks provide too much torque on the e-motor system when engaged in a harder gear from a standstill.

Taos Bakes bar for scale…

Achilles Number Two (Small)

I cannot imagine traveling around the world with this behemoth of an outlet charger. Please make this a USB cable!

TL;DR: Is It Worth It?

If you’re in the market for a do-it-all bike — one you can take to Africa, Central Asia, or South America and ride through extreme conditions on month-long to year-long bicycle overlanding trips and then ride your local terrain on the same chassis — then by all means, a system like the Pinion Smart.Shift makes sense.

If you can adjust your riding style to reflect the system’s 250 Nm load capacity maximum.

These gearboxes are relatively plug-and-play and serviceable by Pinion. If a better gearbox comes out in a few years, you should be able to upgrade easily.

Steve from Viral Bikes summed up the riding experience with three words:

“It’s still quirky…”

But he added this:

“I’ve been riding gearboxes for over eight years and the Smart.Shift is by far the most accurate shifting unit. I no longer have to stop pedaling to shift. It’s instantaneous. But as you’ve found, shifting under full load, in high-torque scenarios isn’t something it’s capable of.”

“Still, I think the main reason gearboxes haven’t caught on is due to the grip shifter, which Smart.Shift eliminates, and the fact that it’s hard to switch between different drivetrains and remember that you have to change your riding habits with a gearbox.”

The engineering alchemists at Pinion developed the most advanced gearbox to date with Smart.Shift. Its Pros outweigh the Cons, in my opinion, and on the right bike, the Pros are elevated even more… check back tomorrow for my Viral Bikes Derive review.

Pros

100% contained
Low center of gravity, resulting in a balanced riding bike (more on that tomorrow!)
Low maintenance @ 10,000 KM between gear oil change
Battery life for 20,000 shifts (estimated) – 3% battery loss over two months’ time
.5 second shift time (it’s fast!)
Zero “sponge” or hesitation with shifting
Shifts (mostly) under load
Quiet, smooth pedaling with no spongy sensation
Increase ground clearance on the rear axle with no derailleur
600% gear spread
17% gearing jumps
17″ gear inches for low-range crawling as reviewed here with 32 t front ring and 34 t rear (which can be increased)
Gates belts are maintenance-free and last for 30,000 km
Can be chain-driven too!
Bombproof housing sealed from mud, water, dust