Why would someone choose custom derailleurs for Herse Bikes when modern electronic shifting systems are readily available and perform exceptionally well? It might seem similar to opting for a manual transmission car in an era dominated by sophisticated automatics. However, for enthusiasts of Herse bikes, it’s profoundly about engaging with the ride. It’s the tactile joy of feeling the gears mesh perfectly, knowing that it’s your input, not a computer’s calculation, that precisely timed the shift.
Beyond this intimate connection with the bike’s mechanics, there’s another critical factor that sets Herse bikes apart: shift times. Contemporary derailleurs are engineered to shift under load, a feature often touted for uphill climbs. Yet, this optimization comes with a trade-off. To guarantee smooth transitions, these derailleurs are designed to introduce a slight delay. This pause allows the ramps and pins on the cassette cogs and chainrings to align perfectly, ensuring a seamless gear change. The duration of this delay isn’t consistent, varying based on the initial position of the cogs. This means the responsiveness between pressing a button and the derailleur actually shifting can feel somewhat unpredictable.
Rider in action during Paris-Brest-Paris on a Rene Herse bike with manual derailleurs
Personally, when climbing, I prefer to remain seated and instinctively ease off the pedal pressure momentarily during gear shifts. This technique works flawlessly when the shift is instantaneous. However, with the slight lag present in many modern systems, I often find myself reapplying power just as the shift finally occurs. This timing mismatch can lead to a jarring crunch, as even the most advanced systems struggle to shift seamlessly under significant power output. While not a major issue, given a choice, I overwhelmingly prefer a derailleur that responds the instant I activate the lever – immediate and without hesitation, a hallmark of the Herse bikes riding philosophy.
The automotive world faced a similar crossroads when transitioning from manual to automatic transmissions. Shift times became a paramount concern for sports car manufacturers. They invested heavily in refining automatic transmissions to achieve millisecond-fast shifts. Today, the spectrum offers choices: a luxury sedan might prioritize imperceptible gear changes, while a high-performance sports car delivers shifts with virtually zero lag. And, notably, manual transmissions still hold a place in performance vehicles like Porsche, catering to drivers who value engagement. In the realm of bike components, the industry seems to be predominantly designing for the ‘luxury sedan’ experience, while the critical discussion around shift times, especially for discerning riders of Herse bikes, remains largely underexplored.
Furthermore, the reliance on batteries in electronic shifting introduces another layer of complexity that some Herse bikes enthusiasts prefer to avoid. Cable-operated shifters, while offering a mechanical solution, haven’t always been ideal. Many require considerable force to operate, leading to rider fatigue, especially on long-distance rides. Stories of cyclists experiencing hand strain and even injuries after extended periods of forceful shifting highlight a real concern. While newer generations of cable-operated shifters have improved, the issue of effort remains a consideration for riders accustomed to the finesse of Herse bikes.
The preference for manual shifting on Herse bikes isn’t about rejecting performance. It’s about seeking a specific kind of performance – one that values immediate response and rider involvement. Modern derailleurs have undeniably raised the bar in terms of shifting technology, and the goal for Herse bikes is to achieve manual shifting that rivals the precision and responsiveness of a high-performance sports car, not the sluggishness of an outdated system.
Rene Herse bike climbing a mountain pass, showcasing its suitability for challenging terrains
My personal journey with Herse bikes and manual derailleurs began in 2011 when building my first Rene Herse. I was intrigued by the Nivex derailleur, having previously experienced it on a mid-century Alex Singer. I wanted to understand its daily practicality. Would it maintain its appeal during night rides, in rainy conditions, or at the culmination of an extended ride?
After logging over 50,000 km (30,000 miles) and countless adventures on that Herse bike, my appreciation for the Nivex surpassed any other derailleur I had used. Ascending the final major climb of the grueling 720 km Raid Pyrénéen, the gear shifts were completely seamless. The Nivex, with its light action and consistently rapid shifts, became an intuitive extension of my body. On Herse bikes equipped with Nivex derailleurs, shifting is a pure, responsive action: pull the lever, get an instant gear change, and enjoy the ride.
Close-up studio shot of the Rene Herse Nivex rear derailleur, highlighting its design and craftsmanship
What makes the Nivex so exceptional for Herse bikes? The primary reason lies in its desmodromic operation. Unlike conventional derailleurs, it lacks a return spring. Instead, two cables control the derailleur, pulling it in both directions. This ingenious design results in remarkably light action, as there’s no spring tension to overcome, and instantaneous shifts, as the derailleur responds immediately when the cable is released. Furthermore, the derailleur cables run openly, without housing, minimizing friction and rendering the system impervious to dirt, a crucial advantage for Herse bikes designed for all-terrain adventures.
But the Nivex’s brilliance goes deeper. The spring that maintains chain tension acts on a lever that moves in a precisely engineered arc alongside the derailleur cage. This clever mechanism ensures consistent chain tension across all gears. This eliminates the chain slap commonly experienced with most derailleurs, particularly when using the small chainring and smaller rear cogs. While modern derailleurs often employ clutches to mitigate chain slap, these add weight and shifting resistance. The Nivex system offers a more refined solution. The consistent, lighter chain tension also contributes to the uniform shifting feel that Nivex is known for on Herse bikes.
Beyond these unique features, the Nivex incorporates all the advancements of modern derailleur design. It features a smoothly operating parallelogram that mirrors the freewheel’s contour, maintaining an optimal chain gap (the distance between the upper pulley and cassette cog) at all times. In fact, the Nivex pioneered these features back in 1938, and it stands as the blueprint for all modern derailleurs. However, in the pursuit of modernization, many contemporary designs have lost the Nivex’s defining characteristics: desmodromic operation and constant chain tension. It’s this combination that delivers faster, lighter, and more consistent shifts than any other derailleur, whether classic or contemporary, making it a perfect match for the performance ethos of Herse bikes.
Jan Heine showcasing the Rene Herse derailleur on a magazine cover, emphasizing its heritage and innovation
An additional benefit, especially for off-road Herse bikes, is the Nivex’s tucked-away location under the chainstay, within the rear triangle. This position offers superior protection. Even if the bike falls, the derailleur is shielded from impact. On most bikes, the derailleur is often the first point of contact with the ground.
When planning my new Herse bike for the 2019 Paris-Brest-Paris, sourcing another mid-century Nivex wasn’t the direction I wanted to take. I aimed for new components while exploring potential improvements to the original design. We refined it with a slant parallelogram, optimized lever arm lengths, and precision-machined it from aluminum and stainless steel. We updated it to be 11-speed compatible and indexable – a surprisingly straightforward task given its inherently light and consistent action. We also achieved a weight of just 178g, competitive with today’s top-tier derailleurs. (A Campagnolo Super Record mechanical rear derailleur weighs 181g for comparison).
Perfecting the new derailleur for Herse bikes has been a multi-year endeavor. The Rene Herse Nivex is not intended as a mere novelty. Our objective is to offer a derailleur that surpasses the performance and durability of the best from the mainstream manufacturers. Like all Rene Herse components, it’s designed to be chosen for its superior function and unique advantages, not for fleeting trends. I’ve been riding the final production version for over a year, and it has proven completely reliable, shifting as flawlessly as the first day. Another bike has been running the indexed 11-speed version with equal success. Furthermore, the new Nivex is fully rebuildable, ensuring longevity. It uses a standard tandem cable, and due to the light shifting action, cable strain is minimal, reducing the likelihood of fraying and replacement. However, should a replacement be needed, tandem cables are readily available at any well-stocked bike shop.
Rear wheel and Rene Herse Nivex derailleur mounted on a Herse bike, showing its integration with the frame
Are there drawbacks to the Nivex derailleur on Herse bikes? One is that rear wheel removal and installation are slightly more involved. The wheel cannot simply drop out vertically because the chain encircles the cassette on three sides. You need to manually detach the chain from the cog and angle the wheel sideways to remove it, reversing the process for installation. The original Nivex incorporated a chainrest – the last cog was integrated into the dropout and smooth (since it didn’t rotate). Shifting onto the chainrest allowed for wheel removal without chain interference. My 2011 Herse bike features this. (It also allows silent coasting on long descents). However, this design sacrifices one cog. Given the rarity of flats, I opted to forego the chainrest on my new bike in favor of an extra gear.
Another consideration, depending on your gearing needs, is that the fixed upper pulley position limits extreme gear ranges. We designed it to accommodate up to a 12-30 rear cassette – ample for my preferences, but those requiring a wider gear spread may find the Nivex unsuitable. Setup also demands some expertise, as there’s no return spring to manage cable slack. To simplify setup, we will offer a cable tensioner to fine-tune cable tension and achieve precise indexing.
A frequently asked question is: When will the Rene Herse Nivex be available? The derailleurs are currently in production, but the numerous small parts, and current bike industry conditions, are causing some delays. Special dropouts are also in development. Since the derailleur is positioned ahead of the dropouts, the dropout slots can be angled slightly rearward, aligning with the fenders for easier wheel removal and installation. A tool for locating the braze-on will also be available. Retrofitting to any steel frame is possible by brazing the derailleur hanger onto the chainstay and adding a guide for the two cables under the bottom bracket.
Rene Herse front derailleur detail, showcasing its lever-operated design and elegant simplicity
What about the front derailleur for Herse bikes? It’s a faithful reproduction of a 1940s Rene Herse design. This derailleur operates without any cable at all – a simple lever push moves the chain between chainrings. While some might call them ‘suicide’ derailleurs, operating a lever-action front derailleur is no more complicated than reaching for a water bottle.
Rene Herse front derailleur in action, demonstrating its direct and positive shifting mechanism
Initially, it might seem rudimentary – lacking even a parallelogram, just a lever moving the derailleur cage laterally. However, its stiffness and direct control result in fast and decisive shifts. The shift quality mirrors that of modern electronic derailleurs, where a motor forcefully moves the chain. It’s also remarkably light at 64g, and eliminates the weight of a shifter lever, cable, and housing. The derailleur floats freely over the chain, negating the need for trimming when shifting at the rear. If chain rub occurs, the derailleur automatically adjusts to re-center the chain.
For this Herse bike, a limit screw has been incorporated. On the original design, the slot length dictated derailleur travel. However, over time, cranksets might seat slightly further on the spindle, potentially causing the derailleur to overshift and throw the chain outwards. An inner limit screw is unnecessary. When shifting to the small ring, the derailleur moves fully inward, providing ample chain clearance. In countless miles, chain drops to the inside have been nonexistent, even for riders new to this system. Perhaps a forceful lever action could induce a drop, but in normal riding, it’s not a concern.
Shifting does require slightly more deliberate action than pressing a button on the brake lever. On long rides like Paris-Brest-Paris, this can be beneficial, providing a subtle stretch and hand pressure relief. Front shifts are also less frequent, as the ‘big’ ring is sized to be versatile enough for most riding conditions, with the small ring reserved for very steep climbs – effectively a ‘one-by plus granny’ setup.
Will we offer the front derailleur in the future? It’s under consideration. Manufacturing in small quantities is challenging. Shaping the cage from CrMo steel is time-consuming and requires skilled craftsmanship. More significantly, precisely locating the square tube on the seatstay demands precision. Historically, René Herse likely used specialized fixtures for efficient production. Perhaps a kit for framebuilders might be offered at some point.
Rene Herse cranks detail, showcasing their lightweight and efficient design
Since drivetrain components are intertwined, mentioning the cranks is relevant. Much has been discussed about Rene Herse cranks. Their net-shape forging and efficient 3-arm design result in exceptional lightness while meeting the stringent EN Racing Bike fatigue resistance standard – a benchmark unmatched by other boutique cranks. They offer a narrow Q-factor and extensive chainring customization. For Paris-Brest-Paris, a 48×32 combination is used. For hillier terrain, 46×30 rings are often fitted for lower gears. Chainring changes are straightforward, without needing crank or pedal removal.
Studio shot of Rene Herse derailleurs, highlighting both front and rear mechanisms
This is the story of the derailleurs on my Herse bike. It’s not that modern derailleurs are deficient; they are simply designed around different priorities. While the Nivex even excels at shifting under load compared to many classic derailleurs, my priority is immediate, positive shifts. I prefer a ‘manual’ bike where the chain is moved by my direct input, not by a servo motor – a core philosophy embodied by Herse bikes.
Here’s an old video showing the front derailleur in action on my 2011 bike.
Other parts in this series:
Photo credits: Nicolas Joly (all except Photos 3 and 7).
