How to Make a Superlight Bike for the “Concours de Machines”

The official results of the 2017 Concours de Machines are in! Peter Weigle’s machine did even better than we thought:

  • Lightest bike: First place
  • Choice of the jury: First place
  • Technical points (bonus for features, penalties for problems): First place
  • Zero penalties for technical problems
  • Faster than required speed on each stage: zero penalties
  • Overall: Second place

We were especially excited to find that the jury appreciated Peter’s bike for its craftsmanship and functionality. Small things like the placement of the headlight make a difference on the road – you don’t ride into a shadow when you corner at night – but they are easy to overlook when evaluating a bike without riding it. The jury consisted of experienced randonneurs who understood the importance of these small details. It appears that they also were impressed by the ease of Rinko’ing the Weigle for travel by car, train or airplane.

You may wonder why the J. P. Weigle didn’t win first prize. The bike scored lower in three areas that were less about the quality of the bike, but were an important part of the Concours:

  • People’s Vote: 6th (out of 24). Most of the visitors were amateur racers participating in that weekend’s cyclosportive, and they probably voted for other, more “modern” bikes.
  • Builders’ Vote: 7th. I don’t think it’s fair to ask the builders to vote, since it’s in their interest to vote “strategically” to give their own bike the best chance at winning.
  • Paperwork: 15th place. Each builder had to submit a presentation that documented the construction of the bike and explained its features. Peter Weigle was so busy building the bike that he didn’t take photos during its construction, and the bike was finished only the evening before the event. We put together the presentation on the train ride to Ambert…

We are honored by the recognition the bike received, and the second place seems entirely fair – the rules were known beforehand. For us, the goal was not to win the event, but to show our vision of the best randonneur bike available today.

Many observers were astonished by how little the bike weighed: 9.1 kg (20.0 lb) is remarkably light for a bike with full fenders, generator-powered lighting, rack, bell, pump, bottle cages and even a mudflap. The Weigle weighs exactly the same as the lightest carbon bike we’ve tested recently, the Open U.P., without fenders, racks or lights. How can a fully equipped steel bike be so light?

Peter Weigle is a master of trimming unnecessary weight from his frames. He went to the limit on this bike, and he also built a superlight stem and rack. For our report in the next Bicycle Quarterly, we will disassemble the bike and weigh each component to show in detail how the light weight was achieved.

We already can tell you that most of the components are standard parts that either are already available, or will be available soon. At Compass, we used the Concours de Machines as an opportunity to work with our suppliers and partners to reduce the weight of our parts even further. Here are some of the components we used on the Weigle:

  • SON Widebody hub: We used the Widebody version of the SON Delux generator hub even though it weighs a few grams more, because wider flange spacing makes for a stronger wheel – useful on the rough course of the bike test. We asked SON to make this hub for 28 spokes – plenty on a bike with wide tires.
  • Pacenti Brevet 650B rims: Finally, 28-hole 650B rims are easily available. Peter Weigle drilled a few extra holes in the rim beds to save a few grams, but otherwise, the rims were standard.
  • Compass Maes Parallel handlebars: We worked with Nitto to make our handlebars even lighter. The latest Compass bars are made to our new, exclusive Superlight specifications. (Only for bars up to 42 cm wide – wider handlebars require extra strength to resist the longer leverage.)
  • Titanium brake pad eyebolts: The Weigle is equipped with prototypes of the Compass René Herse cantilever brakes. The eyebolts for the pad holders are made from titanium. Usually, replacing steel bolts with titanium is not a good idea, because titanium has only half the strength. However, the eyebolts are big to fit over the posts of the pad holders, not because they need to be super-strong – a perfect application for titanium. A limited quantity of these titanium eyebolts is available right now. They fit Compass and Mafac centerpull brakes, as well as classic René Herse cantilevers.
  • Compass Loup Loup Pass Extralight 650B x 38 mm tires: As hand-made tires, the weight of Compass tires varies a bit from batch to batch. The latest 650B x 38 mm tires happen to be especially light.
  • Compass René Herse cranks. A little material was removed from the arms, and the chainring bolts were replaced with aluminum, but the standard cranks are only a few grams heavier. Peter Weigle drilled the chainrings mostly for aesthetic reasons – to emphasize that this bike was special.
  • Gilles Berthoud Galibier saddle: remarkably light for a leather saddle, yet supremely comfortable. We removed the stiffening bracket – needed only with seatposts that don’t clamp the rails securely – to reduce the weight further.
  • Nitto 80 bottle cages: As light as many carbon cages, but removing and replacing bottles is much easier with these cages. Plus, they gripped the bottles securely even on the rough mountain bike trails that made up much of the bike test of this year’s Concours.
  • Maware handlebar tape: Made from pigskin, this leather tape is beautiful and comfortable, yet remarkably light.

For the Concours, the bikes were weighed with bags and tools. Fully equipped for the road, the Weigle came in at just 9.7 kg (21.4 lb). We chose not to bring any tools, because we had total confidence in the bike. That saved valuable grams. Other bikes carried ultralight tools, but we’ve found that a well-built and well-assembled bike rarely needs work on the road.

Back to the bags, Compass worked with Gilles Berthoud to make a superlight prototype handlebar bag that weighs just 266 g (left). It uses the same materials as standard Gilles Berthoud bags (right). The weight savings are the result of leaving off all side pockets and reducing the size of the leather trim to a minimum.

Our goal was not to make a crazily-light machine that would last only one weekend, but to show what can be done with functional and durable components, if every part is optimized for light weight and performance. Some parts, like the SON Edelux II headlight, were chosen for their function more than their light weight. There were a few superlight parts, like the titanium bottom bracket, the Campagnolo Record titanium cassette, and the titanium Crank Brothers pedals, but they are all proven components that should work well under a smooth rider. Apart from the superlight frame, there isn’t much magic in the bike, just a careful choice of components. When spec’ing the bike, we avoided anything that could compromise reliability or performance. And since this will be my own bike, I look forward to riding it for many years to come.

Click on the links in the text to find out more about the components. Click here to read more about the 2017 Concours de Machines. A full report of this amazing event will be in the Autumn 2017 Bicycle Quarterly.

About Jan Heine, Editor, Bicycle Quarterly

Spirited rides that zig-zag across mountain ranges. Bicycle Quarterly magazine and its sister company, Compass Cycles, that turns our research into high-performance components for real-world riders.
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72 Responses to How to Make a Superlight Bike for the “Concours de Machines”

  1. Richard says:

    Why 38mm tires? Looking over the rough course, 42mm tires, or even 48mm, would seem more appropriate. Was the extra weight the deciding factor?

    • Yes, lighter weight. The 38s gained us a few points for light weight, and we didn’t lose any points on the course, so they were a good choice. Wider tires would have been faster, but we already exceeded the required speed, so that wouldn’t have gained anything…

  2. Alexander says:

    Congratulations! Looking at the bag: whay not make it expandable with straps/cord like the campeur bags?

    • We tried to make the bag as light as possible. An expandable handlebar bag is an interesting idea, but it’s actually better to carry the weight at the bottom, and leave the top part empty…

      • G Hall says:

        That prototype bag seems like a very good balance of weight and practicality. Are you considering offering it as a production model? Personally, I remove side pockets that get in the way of shifters and I don’t find the other pockets all that useful.

      • The bike for the Concours de Machines was a team effort that involved many of our suppliers. We were especially happy that Berthoud pulled out all the stops in making the bag. One reason the carbon bike weighed 2.3 kg (5 lb) more than our bike was that Cyfac is the French importer for Ortlieb, so they felt constrained to use a (very heavy) bag from that maker.

        Our goal was to push our product design to the limits of what is possible. Everything on the bike can be viewed as a prototype, and we are working with Gilles Berthoud on a production version of the superlight bag.

  3. Stephen Bamford says:

    Mr. Weigle’s bicycle should have won 1st in all areas. It is unfortunate it did not. But that it scored so well considering how most folks voting lack the understanding for the reasons ‘steel is real’ and the time-tested sustainabilities of bicycles like Mr. Weigle’s. The engineering is not only ‘spot on’ in his work but so is the artistry. Thanks to Mr. Heine, perhaps one day, the rest of the people will finally awaken to Mr. Weigle’s and Mr. Heine’s ‘new old’ technology. 😀

    • Thank you for the kind words. However, the rules of the event were clear from the outset. Our goal was to build an amazing bike. but we didn’t do everything possible to win the event.

      • Vincent says:

        Your reply is a testimony of your fair play spirit. I guess for readers of your blog, the fact that it lost first place because of lack of documentation is irrelevant. What’s interesting is the bike, your approach to building for best fit for purpose: riding on-road and off-road. I think this usage scenario will become mainstream very quickly. I live in France near the Cévennes and as roads (even country roads) get upgraded for optimal car-driving experience, they become more boring for cyclists (riding on wide roads is less enjoyable than on a narrower one, all other things being equal). There are endless opportunities to have fun on small roads combined with dirt paths (in Europe at least). Because people were led to believe that real riders need to ride road-racing bikes to be taken seriously (or MTB), they kept away from interesting areas with small roads, ill-suited for racing bikes. Randonneuring has a very old-fashion image around here, but now with gravel bikes looking like the new cool stuff to have, it will bring back many more people to riding bikes capable of handling all kinds of terrain including some which people felt required a MTB.

  4. Pawl Bearer says:

    Wow, impressive bike and results. I didn’t see anything about the decaleur you used. Was it the standard Compass part?

  5. Erick says:

    what pump you use in this bike? it´s a standart model?

  6. Jack Loudon says:

    As this will be your personal bike, it will be very interesting to see how it holds up over time, and what modifications (if any) you will make. I think of such a lightweight bike as being delicate, but I expect you will prove me wrong 🙂

  7. Phil says:

    I built frames on and off for 40 years and admire this bike greatly. As to the tubing used I would comment that bicycles are, for the most part, incredibility over built. I once built a bike with the lightest tubing I could find-True Temper standard size-and it rode as well as any bike I ever made and I’m 6’3″ and weigh 200. I don’t know that I would have made it for a customer because you could dent the tubes if you weren’t careful.

    • Most of my bikes are made from superlight tubing. You are right, it dents more easily, but it has proven very durable, and the ride quality for me is superior to heavier frames – what we call “planing”.

      • Phil says:

        I should probably qualify the “lightest tubing” comment as I could have used a KL set because my friend Brian Baylis would have given me one but it was a bit too light.

  8. Akny says:

    I truly love this bike and its components, but I think the emphasis on weight is a little misplaced. The identical components on the a titanium or carbon frame would have been lighter still without sacrificing durability (major sacrifice in style though). Even a carbon fork on the above Weigle Concours bike would have saved at least 1/4 pound without affecting durability. Cantilever brakes are also a big advantage in weight when compared to a disc braked bike. I love the Weigle though and would love to ride it as is.

    • A carbon fork wouldn’t be available with the geometry for optimized handling with wide tires and a front load. Also, putting a rack onto a carbon fork isn’t easy… As to a titanium frame, I doubt it would be lighter than the Weigle’s steel frame. We haven’t weighed it yet, but the frame must be very light to get the bike weight down to 9.1 kg.

  9. Bill Lindsay says:

    What will happen to the bike now? It’s perfect! I hope it will be ridden a lot. I think it would fit me if Peter needs a customer or volunteer

  10. Han-Lin says:

    I agree that bikes shouldn’t be too heavy even when it’s not a race. There’s safety and practical reasons. A lighter bike can be beneficial for public transportation where we have to carry our bikes on the stairs or load it on the rack of a bus. My sister’s non-suspension MTB is very heavy with a metal basket. It almost fell when she was loading it on a bus. The bike feels heavier than my commuter with a metal front basket and a rear rack. Once I put two disc horns on my road bike, I could feel the difference when lifting the bike.

  11. Brad says:

    Jan, I’d like to hear your feedback on the gutted Ergopower levers. Does the void where the shifting mechanism used to be feel uncomfortable/strange when gripping the hoods?

    • They worked great – I couldn’t feel the void. In fact, Campagnolo used to offer Record brake levers that were nothing else but gutted Ergo levers, from what I hear.

      • Brad says:

        Yes I had some of those – they were based off the 10s Record carbon shifters. With that design the shifting mechanism was more internal in the body so there was less of a void when removed.

        Good to hear that the 11s version seems to work in gutted form, I think I’ll give that a whirl myself.

    • Jack Loudon says:

      I have some Record brake-only levers I bought about 10 yrs ago, and the void is filled with a plastic piece.

    • Frank says:

      Having removed the guts from an 10-speed Ergopower repurposed for a 1-speed, I learned that the central bolt running through the rachet mechanism has a structural role. The ratchet is not essential but its axis should be retained for the integrity of the lever.

  12. quel était votre boitier de pédalier ?

  13. marmotte27 says:

    En dehors du challenge de construire un tel vélo et du fait que c’est un Weigle, why did you feel the need for a new bike, if I may ask? It doesn’t seem to add any really useful features to your existing bikes, and in some ways seems to fall back behind them, cantilever brakes instead of centrepulls, narrower tires, less versatile as a travelling bike than your ‘Mule’…

    • I’ve wanted one of Peter Weigle’s bikes for a long time. As you can read in our “First Ride” trst in the Summer Bicycle Quarterly, his bikes feel different from the ones I usually ride.

      Most of all, the Concours de Machines provided an opportunity for everybody at Compass, as well as our suppliers, to think hard about further refining the performance of our components. As they say anout horses: “Competition improves the breed.”

  14. Katharine says:

    Will those ti eyebolts be an option when purchasing new brakes, sometime in the future?

  15. Chad says:

    Beautiful machine! Congratulations to you and Peter. What a fantastic bike to add to the stable. Did you commission the build and decide to enter it in the competition or did you decide to purchase it after riding in the competition? Just curious.

  16. Rick Harker says:

    Hi Jan, I’m curious about the frame geometry for this build. My curiosity stems from seeing the majority of bicycles with set back seat posts, or is that for a reason.

  17. cat6champ says:

    Looks solid! Except for the pedals. I’ve had a pair bail on me during my last tour. The bearings are miniature.

    • Agreed, Egg Beater pedals are rubbish. After having the bearings crap out on me a couple of times when I raced MTB I went back to Shimano. The minimal weight saving was not worth it in the long run.

    • Conrad says:

      I have not found those pedals to be very durable either. Luckily, inexpensive rebuild kits are available.

  18. Noel Hoffmann says:

    Can you give us specifics about the tubing?

  19. Peter Weigle’s randonneur on the last BQ issue was also sporting 38mm tires. Does this bike have sufficient clearance for 42mm?
    Does the decision to run 38mm stem from a framebuilding perspective (less bending, perhaps stiffer chainstays) or from intended use for the bike (more paved road oriented).
    I think I read somewhere that this bike has 40mm trail, instead of the mid 30’s of your Hersé. Did you choose this larger trail number due to the decreased pneumatic trail of 38mm tires?
    This bike is a true tour de force, I think it masterfully applies what you learnt from riding your Herse with more contemporary componentry.

  20. Bertrand says:

    There’s a 44 pages article on the concours in the French magazine “200” out now. All bikes documented and photographed in detail.

  21. peter weigle says:

    We choose 38mm tires because they were lighter than 42’s and Jan being an expert rider would do well with them.( He would have been faster on the rough sections with 42’s but his finish times were well within the limits for the event).
    Regarding the frame design and details. I asked Jan for his preferred seat tube and top tube dimensions. I designed and built the frame with those in mind. It is a low trail design with front end geometry similar to builds I do for my customer’s.
    I enjoyed the back and forth with Jan as we decided on component selection and last minute details. It was an honor and a privilege to build this bike for the Concours de Machines and for Jan.

  22. Dr J says:

    When I think that this machine weighs only 9kg WITH fenders, rack and a generator hub, I think – impressive! But then, after a closer look, it’s pretty clear that some simple tricks were used to keep the weight down, namely downtube shifters (significantly lighter than integrated shifters) or canti brakes (lighter than discs). I’m guessing a bicycle like this could be made even lighter if it wasn’t limited by “rando rules of engagement”.

    • If we hadn’t wanted to use modern derailleurs, the bike could have been lighter yet. The indexed Campagnolo shifters are quite heavy…

    • Jacob Musha says:

      Dr J – funny that you consider downtube shifters and cantilever brakes “tricks.” When I ordered my custom enduro allroad bike I specified both. Not to save weight, but because I wanted the best bike possible.

      Regarding your post below, I echo Mr. Weigle’s question: if it “shouldn’t be difficult” then show us all the other bikes with lights, racks, pump, and fenders that weigh less.

      • Conrad says:

        I agree. For a criterium or cyclocross race I will take a brifter but for any other use I prefer downtube shifters. Its good to move your hands around a little, especially if you are doing really long rides. Inexpensive, lightweight, and non indexed ones will universally shift anything. Not a trick, just the right tool for the job! Wide profile cantilevers are the kings of light weight and reliability. Maybe they don’t have the absolute power of hydraulic discs, but again, the right tool for the job for this kind of bike.

  23. Steve says:

    What a treasure that bike is! Thanks for sharing the details.

    Is the cable pull of modern ergopower levers better matched to centrepulls or cantilevers?

    Thanks

    • The cable pull of the Compass centerpulls and of the René Herse cantis is very similar, so both work equally well with modern levers. I had used René Herse cantis only on classic bikes, and I was impressed how much power and feel they had with modern levers.

  24. Why not painting the whole bicycle in blue? Is there a practical reason to apply chrome on half the forks and rear triangle?

    • It’s actually nickel. Paint on the dropouts tends to chip off from the pressure of the quick releases, but the main reason for the bright finish is aesthetic. There is no copper filler underneath the nickel, so the finish does not add weight.

      • Phil says:

        I’ve had a lot of plating done and copper is always the first layer. Copper, nickel, chrome. Nickel has a lower sheen with a slightly yellow cast and tarnishes unlike chrome. Before WW2 nickel was the norm but chrome was widely used in WW2 because it’s harder and longer wearing, factors the military liked. After WW2 there wee lots of plating plants with lots of experience with chrome and its use exploded.
        Personally I prefer nickel.

  25. peter weigle says:

    Dr. J,
    If it was THAT simple to build this bike weighing only 9kg, why aren’t they all this light?
    If you look at test weights of fully integrated rando bikes tested in BQ over the years you might realize that more than “simple tricks” are required to have a bike be this light.
    *The main reason the down tube levers are used is to simplify rinko compatibility/use, not as a weight savings measure.

    • Dr J says:

      I don’t mean to imply that this bike is so light only because of some simple modifications, such as using lighter brakes, etc. I realize that lots of engineering thought was put into this project to optimize its design.
      But at the same time I think it shouldn’t be difficult to build a bicycle with fenders and a SON hub that weighs less than 9kg. It just wouldn’t be a rando bike with geometry you chosen here.

      • it shouldn’t be difficult to build a bicycle with fenders and a SON hub that weighs less than 9kg.

        I think this would be more difficult than you may realize. Consider the Open U.P. we tested recently that weighed exactly the same as the Weigle. The Open had Di2 and wider tires, but the Weigle’s fenders, lights, rack, pump and bell more than outweigh that.

  26. peter weigle says:

    The nickel finish on the lower portion of the stays and fork blades is more chip resistant than paint. That was a consideration of mine realizing this bike would be broken down for rinko and also hard case travel. Imo it is more than just an aesthetic consideration
    The nickel finish is only millionth of an inch thick, light yet very durable.

  27. Austin says:

    I almost can’t believe this bike. The proportions and stance are perfect, the weight seems almost impossible coming from my own smaller 24lb 650b *without* generator/lights/rack. Congratulations Peter!

  28. Jolly LLB says:

    It really awesome article. I can’t believe this bicycle. I realize that lots of engineering thought were put into this project to optimize its design. Thanks for sharing a great content.

  29. wilzan says:

    Jan, I’ve noticed on your more recent personal bikes you’ve been choosing the Maes parallel over the Randonneur bars. Just curious, what was your criteria in deciding one vs the other?

  30. James says:

    Jan, could you expand on the point made about the light positioning and cornering? I have the same light mounted to my fork crown and find tight corners can mean riding into the dark. Fitting a light on another bike lower down the fork helps bring out shadows and depth perception, though I’m missing how the position on this bike changes the light field much over a fork crown mount (that I assume you don’t use due to the bag position). Lovely bike by the way, right down to the colour and finish.

    • Your issue is unavoidable – during slow, sharp turns, you always ride into an area not illuminated by the light’s beam.

      The issue with a light mounted lower than the top of the tire is that the front tire casts a shadow. If the light is too far back, that shadow falls so that you ride into the dark even during high-speed turns – not a good idea! On the other hand, placing the light far forward or far outward to avoid this makes it vulnerable and doesn’t look very elegant. Fortunately, there is a “perfect” position where it all works out great.

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