The age-old derailleur versus gearbox conundrum. People often say they want gearboxes, but we rarely see them. People often say that derailleurs are junk, but when it comes to the polling station, the masses don't appear to find fault with their derailleurs. Gearboxes are renowned as heavy and inefficient. Derailleurs save weight and spin easily, but are left hanging to receive the brunt of mother nature's forces.
Times, however, are changing. New technology and manufacturing techniques have been continuously increasing strength and reducing the weight of both systems. Surely, with the introduction of SRAM's Eagle and its whopping twelve gears, modern chain-retaining rings and quieting clutches, the derailleur (as we know it) has been developed to its limit. Though lesser-seen, the gearbox has also been around for a long time. Does it have enough room for improvement, or is it already maxed out?
Personally, I'm a big fan of the gearbox. Probably because I lack precision on the trail and I log plenty of time riding on gnarly, ungroomed, alpine terrain, which makes for plenty of potential bike-smashing moments. Many riders share my gearbox dream, but a great number, including most of my colleagues and peers, have little interest in gearboxes and are happy with their conventional derailleur systems.
Each system has its positives, and each has its compromises - topics that have fueled an ongoing debate about which transmission is ultimately the best solution for a mountain bike. To properly debate these burning issues, I asked the people at Nicolai to build two identical bikes, one with a gearbox and one with a derailleur transmission. I would then put them to task on the same terrain for both timed runs and for riding impressions. In addition, I would provide weights and technical comparisons to hopefully flesh out the best and worst of the gearbox and derailleur - and, ultimately, conclude with a clear winner.
For those of you who have yet to form an opinion, here's the general breakdown:
A Derailleur Promises:
• Light weight and high efficiency • Easily-sourced parts due to higher production volume • Lower prices due to higher production volume • Easy maintenance due to the external nature and cross-compatible components
A Gearbox Promises:
• Protection of moving parts from the elements, debris, and strikes • Little, or infrequent, general maintenance • Improved unsprung:sprung mass ratio, therefore suspension action and grip • Increased ground clearance
Nicolai has been producing gearbox bikes, including their own G-Boxx projects, for as long as I can remember. Their latest Ion GPI bike blends a 12-speed Pinion P1.12 gearbox, a Gates Carbon belt drive, and Mojo-developed Geometron geometry. Nicolai provided me with an Ion GPI and a matching, derailleur-driven Ion16 Geometron, each with a near-identical build kit.
This isn't at all integral to the comparison aspect of this review, but I feel it needs mentioning. For those who haven't seen a Nicolai in the flesh, the handcrafted detail and finish of their aluminum chassis is superb, a bike geek's wet dream. Photos never do these bikes justice, especially in the stealth, black-anodized finish.
Both Nicolai Ions were built with Fox suspension: 36 forks and a Float X shocks with the same tunes. Hope provided cranks (derailleur-bike only), wheels and brakes. Continental provided traction, and a RockShox Reverb provided a perch. Transmissions were powered by SRAM's X01 11-speed, and Pinion's 12-speed P1.12 gearbox.
Weight and Cost
A few notes about the gearing: SRAM declined to provide an Eagle system for an equal test of 12 vs 12 gears, as they didn't have any in stock at the time. Since the test, Pinion has released a new 'C' version of their box which drops the claimed weight 250 grams, to 2100 grams for the unit. Pinion also offers the 18-gear, P1.18 version, for a few more dollars and an extra 350 grams.
For comparison's sake, a SRAM Eagle XX1 drivetrain, including cranks, BB, shifters, derailleur, chain and cassette weighs 1553 grams. The Pinion P1.12 gearbox alone weighs 2650 - but you'll need to add the crank arms, two belt guides, and the Gates belt and sprocket assemblies to that figure to make an accurate comparison based upon the components of each system. The difference in the overall weight of the gearbox vs the derailleur bikes is 1.78kg. One must assume that the mounting plate for the Pinion gearbox is a fraction of the sum, but if you add that figure to the Eagle drivetrain, the total weight of the Pinion transmission comes in at about 3330 grams - a bit less than double the weight of the best 12-speed derailleur system.
There is also a wide price difference between the pair: the Ion GPI with the Pinion here retails at €7400 Euros, versus the ION Geometron at €6350. That's about $7926 USD against $6804 USD at today's rate.
Gear Ranges and Spacing
The 12-speed Pinion system provides a 600% gear range with equal 17.7% steps between each gear. SRAM's 11-speed setup only provides a 420% range, with more erratic steps, ranging from 12.5% to 20%, while the 12-speed Eagle drivetrain still comes up comparatively short, at 500%, with gear steps also ranging from 20% to 12.5%.
The classic SRAM trigger shifter undercarriage is superbly ergonomic with light shifting. The two different click feelings when moving up or down gears makes it easy to remember which lever to push. It also doesn't affect your grip choice and only has one cable that needs routing, unlike the pair on the Pinion.
The Pinion's Grip Shift-style selector is more clunky. Even after spending plenty of time on the bike, and however used to it I became, I would still get confused with the similar clicks and change in the wrong direction. I didn't have any issues accidentally shifting when riding and think this would be hard to do, but I do have some experience controlling a motorbike with the throttle.
When changing down into an easier gear with the Pinion system, a slight pause or let up on the power is needed. Definitely not ideal when climbing up steep sections that require consistent power to make it to the top. The rest of the time I had no problem shifting and the rider will learn, in time, the nuances of easing the power to allow the shift to happen, it's the same as changing with a derailleur system; you can't simply change gear under full power. Over time you learn to feel the correct pressure and allow the gears to change smoothly.
The upsides of the Pinion are that you can change gears at any time; pedaling, coasting or standing next to the bike supping espresso, showing the boys how you can switch 12 gears on the spot. This freedom can, and should be used to your advantage, preselecting gears before climbs or preparing to sprint out of corners.
The Drop Test
What does a drop test tell us? Well, if the bike bounces, then the rear suspension hasn't absorbed the impact and energy returns upwards through the bike from the ground and lifts the bike off the floor. Both bikes had an identical shock tune, but the Pinion version has less unsprung weight, meaning the rear wheel should be able move more easily into the suspension travel and absorb the impact. It's important to note that the gearbox bike's heavier overall weight will help it stick to the ground too.
The Pinion bike offers the chance to make you feel like a boss performing this in front of your buddies, with no bounce and no noise prior to the macchiato round.
The gearbox-equipped bike weighed 1.78kg / 3.92-pounds more than its derailleur-loaded counterpart. Neither of these bikes, however, could be described as light. But, the first major argument for a gearbox equipped bike is the movement of unsprung mass to sprung mass. Unsprung mass is anything that moves below the fork stanchions and lower shock eyelet. That would be the fork sliders, wheels swingarm, linkages, brakes and cassette sprockets. Motorsport engineers will spend hours to improve this ratio by fractions of a percent. The Pinion bike's single rear sprocket and simple chain idler reduces the unsprung mass of the rear suspension.
In a recent Pinkbike poll about derailleurs and breakage, an overwhelming majority of people said they hadn't' broken a derailleur in the last two years. In this case, I'm either an inaccurate hack on the bike, or in the workshop - or I crash too much. I have snapped two derailleur hangers in the last two months, destroyed a mech, snapped a chain, and have gears that don't quite work properly. So, ground clearance is a big deal for me, and something gearbox proponents and manufacturers also like to shout about. But, how much difference is there in reality?
At the danger end of the drivetrain, the SRAM 11-speed derailleur has just over 19cm of clearance from the ground when set in 6th gear. This decreases when speed rises and higher gears are selected. The derailleur moves down the cassette, but this also moves the derailleur away from the wheel towards oncoming trail traffic. When moving into a lower gear, the derailleur moves inwards and away from obstacles, but also extends down towards the ground. This also moves it closer to the spokes where damage can happen if something manages to push it into your rotating wheel.
The Gates carbon belt drive is a direct, single-speed system and the belt is always travelling in the same line. The rear sprocket has a massive, 29cm of clearance to the guide. Nicolai uses a standard 142mm width hub to give the correct belt-line, but the frame could be improved by using a narrower, single-speed hub, this would slim down the swingarm and perhaps, shelter the drive sprocket more effectively.
At the chainring, the derailleur bike had 27cm of clearance from the 34t chain ring to the floor. The Pinion bike comes with an integrated bash guard and chain tensioner which sat slightly higher at 27.5cm from the floor. The Pinion system also looks better for attempting Danny Macaskill style log slides.
There was a massive difference between the two bikes. Most of the riding I did was lift assisted with some pedaling up to various peaks in the Portes Du Soleil, France. In this area, I would choose the Pinion bike hands down, every ride. Yes, it's heavier, but this was only a hindrance when getting it onto lift hooks. It didn't pedal as swiftly as the derailleur bike, but on the downs, it was another–better-–beast. The gearbox bike was so much quieter – almost silent, offered so much more grip and inspired so much more confidence when heading into gnarly sections.
I set five downhill segments and rode them each four times, 40 timed sectors in total. No pedaling, standing starts on Le Pleney. I chose simple sections, including one fire road section (Stage 5) at the end of the trails, to take away rider input as much as possible. On average, the Pinion bike was nearly three seconds quicker over a 3.5-minute track. Huge.
After riding both bikes, I would argue that in very technical, rough, and loose trails the Pinion machine would chip away at even more time, if not purely because of the extra confidence it gave to hammer through sections.
I was undecided whether this was due to the reduction of unsprung mass, the increased amount of pick up (due to two freewheels creating more slack in anti-squat) or the heavier weight of the complete bike. Heavier weight? But hey, people keep telling me a lighter bike is a faster bike? I can't find any evidence that a lighter bike is faster downhill, and something that makes me think the opposite is when I'm trying to follow a heavier rider down the hill. Try following a buddy who is 15kg's heavier than you and see who rolls the fastest.
If I lived in an area where regularly pedaling the bike to the top of the hill was needed, I think I would choose the derailleur bike. I generally don't mind grinding a heavy bike to the top of the hill, but the 17kg gearbox brute was a bore. I couldn't calculate how much, but the Pinion bike does drag more than the derailleur bike with a clean and lubed chain. The derailleur bike had more inherent anti-squat in easier gears, which made climbing easier by sitting the bike higher in the travel and pulling the bike up and over steps more easily. Technical climbing is also made more difficult on the Pinion bike; the pair of freewheels increase the engagement interval, which hampers quick, half-pedal strokes when things get trialsy.
For downhill, I am convinced the Pinion bike has a huge advantage, but for XC, it loses out. How about trail riding or enduro? That's still a big, gray zone for me and the answer depends on what this type of riding really is like for you. If you have the horsepower to get the Pinion to the top of a long, mellow road climb followed by a long descent (like we find in Europe), your trip will likely be faster and more fun-filled on the way down, providing there aren't too many techy climbs snuck into the trail. On the other hand: if your trail riding is more akin to a UK trail center, or North American trail, where the ride constantly switches between ups and downs, the derailleur bike is likely to stay ahead here.
The gearbox dream of never breaking a derailleur? Well, the only part of either bike I managed to break during the test was the chain tensioner on the Pinion. The belt would derail if the bike was rolled backward more than a few meters (not when backpedaling) and during one attempt to re-fit it, I managed to break part the very heavily-sprung tensioner with my overly huge biceps.
The second gearbox dream of the ever-clean belt was also destroyed. Over multiple days of riding the belt drive did an excellent job of self-cleaning and never required any maintenance or even a scrub. But, on one exceptionally muddy and sticky day in Les Gets–20cm deep mud conditions–the front sprocket did clog up after it became overwhelmed with mud. The belt almost started to derail, as the packed mud lifted it away from the teeth. Some trail-side stick therapy remedied this. I figured that the accumulation may have been caused by the amount of freewheeling down the hillside, and that more time turning the pedals may have helped to clear the blockage.
The final question is: Which one would I choose? That is a tough one, but I would go with the Pinion bike for Alpine-based and uplift-assist riding, the 155mm travel Pinion bike is a killer, and a downhill version would surely be a winner. If I was back in the UK, pedaling more and lapping trail centers and local woods, I would take the derailleur bike, but then there's the mud, grit, cleaning and tuning to contend with... - Paul Aston