Tubular Stays and Other Fender News

Many years ago, a big magazine published a note about Honjo fenders, which were just starting to trickle into the United States, and noted: “We are charmed by the idea that there actually are fender snobs.”

Those days are long over: Today fenders are recognized as an integral part of many performance bikes. Those of us who ride year-round need fenders that not only keep us and our bikes dry and clean, but also don’t rattle, resonate or break prematurely. We also want them to offer as much performance as possible.

Tens of thousands of miles of riding with fenders have shown us what works and what doesn’t. Honjo’s aluminum fenders keep us drier and are lighter and more aerodynamic than any plastic fenders we’ve tested.

The fenders Compass sells are made by Honjo to our own specifications. The most noticeable detail is the added coverage: 165° on the front and 200° on the rear. On the front, that means no spray on your feet and bottom bracket/chain (further helped by a short mudflap). On the rear, the fender can extend beyond the bottom bracket to keep the chain dry and clean even in crosswinds. These are small details, but they make a large difference.

One reason why we’ve found Honjo’s fenders so superior is their stays. They run all the way around the fender, rather than connecting to flimsy flat brackets. This makes them stiff and strong. The fenders we sell at Compass come with our own Rene Herse eyebolts (above). Not only is their rounded shape more elegant, but the threads are 7 mm long – exactly the right length, so the bolt doesn’t stick into the fender any further than needed. And the special ‘Tensiloc’ nuts we use prevent the fender bolts from loosening.

That hardware adds a little to the cost, but it means that you can install these fenders and forget about them. I’ve yet to re-tighten a fender bolt on my current bikes, even though my Urban Bike has seen more than a decade of hard use in the city, and my Rene Herse that has done 2 Paris-Brest-Paris, 2 Raids Pyreneens, the original Oregon Outback and countless other challenging rides.

To save weight on my Herse, I used tubular fender stays. I found the raw material among the stocks we got from Lyli Herse when we bought Cycles René Herse. They were left over from the 1940s Concours de Machines technical trials! My tubular stays have been 100% reliable, and they save 35 g, so we’ve asked Honjo to make tubular stays for our fenders (above).

Starting today, the tubular stays are available as an option on all fenders we sell. We also offer them separately as a retrofit.

We’ve got more fender news: The Gilles Berthoud fender stays are modeled on a style found on many Jo Routens bikes. It’s an elegant design that is also useful if you are fighting toe overlap on your bike.

The flat section on the rear of the stay attaches directly to the fender. That eliminates the eyebolts that stick out a few millimeters. It can make the difference between catching your toe or not.

Berthoud fender stays come with a matching bolt kit (not shown). You can also rivet these stays directly to the fender to save a little weight.

We also stock plastic R-Clamps from Gilles Berthoud to attach the fender stays to the frame or fork. These are useful if you want a safety release on your fender stays: The stay will pull out of the plastic clamp if a foreign object gets caught between fender and tire. This is useful if your fenders are mounted with less-than-optimal clearances, as it reduces the risk of the fender collapsing and jamming into the fork crown.

 

Why not use the plastic R-Clamps on all bikes? When you ride on rough roads, the stays can work loose over time. Check them periodically to make sure.

Since our bikes wear their fenders year-round, and we ride on gravel and in the forest, we take fender safety seriously. We’ve researched this, and here is what we’ve found: If you have the recommended 20+ mm clearance between tire and fender, objects that are small enough to be picked up with great force will go through the fender without causing any harm. Large objects have too much inertia to accelerate to a speed that allows them to do much damage. The fact that aluminum fenders is far stiffer than plastic ones helps in this respect. Wider fenders are stiffer than narrower ones, making them even safer.

During our research into fender safety, I asked all the old randonneurs I know in France about fender-related accidents. Nobody remembered any, even though these guys and women rode tens of thousands of kilometers a year – fast. I heard about all kinds of crashes, but everybody agreed that their aluminum fenders were completely safe.

If you have sufficient clearance between tire and fender, we recommend the metal Honjo R-Clamps. (Our fenders come standard with them.) They are more elegant as well as more secure. They will never come loose. You can use either clamps with all fender stays we sell.

Often overlooked, yet very important: a third attachment point for the front fender. Every fender needs three attachments to stabilize it in three dimensions, so it’s silent and doesn’t resonate on rough roads. With just two attachments, the fender can twist and flex, which can bring the fender’s trailing end in contact with the tire. Then, the tire pulls along the fender, which risks collapsing and jamming into the fork crown.

Many randonneur bikes have racks that incorporate the third attachment point for the fenders. (All Compass racks do.) If you don’t plan to use a rack with a fender attachment, we sell single Honjo fender stays to stabilize the front of the fender. The single stay comes with two R-Clamps and a single eyebolt to attach it to your fender and fork. The most elegant solution is to mount the stay to mid-fork eyelets (above), but you can also run it stay all the way down to the dropout eyelets as well.

We have to say that we are quite excited about the fender news here at Compass. Does that make us ‘fender snobs’? Ask us when we hit a rainshower on a long ride that crosses multiple mountain ranges and continue without undue suffering!

Click here for more information about Compass fenders.

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 the high-performance components we need for our adventures.
This entry was posted in Uncategorized. Bookmark the permalink.

43 Responses to Tubular Stays and Other Fender News

  1. Grant says:

    That picture of the Berthoud fender stay made my morning; what a textbook example of form following function.

  2. ascpgh says:

    Thanks for being catalyst to the inertia of “fender snobbery”.

    That tagline is dismissive and indicates to me the writer was patronizing the audience they have cultured favoring the popular bike media paradigm OEM CFRP racing box bike…”stiffer, lighter, blah, blah”. No room for “heavy” fenders. That paradigm’s cyclists activity includes ride sections more contrived than laboratory experiments, most defined by Strada segments. These are cyclists of limited experience with the environment in which they ride and certainly don’t have destinations in mind. They winter indoors on spin bike video games.

    I ride year round for transportation, recreation and travel. Fitness comes with that, not for competitive needs. I’m tuned to fenders because I want them to keep me and my bike clean and functioning. Eighty miles in the rain on an off road ride: https://photos.app.goo.gl/EpPZLFpYFyzaKZHX8
    Dirt on the fork from forward flung spray, but BB, chain and chainrings are clean. No grit or grinding in the drivetrain.

    Yeah, I’m a functional fender snob in that I appreciate what works and doesn’t from my own use.

    • The quote about fender snobs is from many years ago, when Honjo fenders were available only in Japan. A few had been brought over by Grant Handley (in his carry-on luggage!), and Bradley from American Cyclery had given a set to Bicycling. Back then, the cycling world was still neatly split into road and mountain bikes, and these fenders didn’t fit anywhere.

      I have to admit that I first put a set of those first North American Honjos on my bike because I liked their looks. It was only when I was caught in the rain that I realized how much better they were at keeping the water inside.

    • Andy says:

      Snobbery indeed. While I by no means am someone who can afford a bike for every occasion, I do realize the fact that beating personal Strava records in summer on a purebred racebike is one type of fun, and a fully loaded/prepared winter bike in the dark seasons is a different form of two wheeled gratification. One day I hope to have a classic steel and fendered bike one day (albeit with disc brakes) for these Seattle winters, but I will NEVER zip around town laden down with unnecessary parts when not needed!

      • I will NEVER zip around town laden down with unnecessary parts when not needed!

        I used to think that way. At first, I refused to use fenders: “Had those on my bike when I was a teen. It was SLOW.” Then I installed fenders, but took them off every spring – summer thunderstorms be damned! Then I got a rain bike, to have a second bike ready when the forecast was iffy. (I realized that I rode my rain bike more often than the ‘good’ one.)

        Finally, I realized that my misconception – fenders make your bike slow – was because most bikes I’d ridden with fenders were slow to begin with, and the fenders were just coincidental. I realized that a good bike with good fenders is not significantly slower, nor less fun to ride, than a racing bike. (You can do the physics at analyticcycling.com or just trust our side-by-side testing.) At that point, I realized that even Ferrari and Lamborghini sports cars have fenders and lights. They aren’t any less sporty for it, and neither are our bikes.

  3. Deacon Patrick says:

    Suggestions for running fenders with nobbies? Specifically Steilacoom and 2.1” Racing Ralph 29ers. Thinking specificaly of some of the Pass Hunter photos showing fenders on bikes riding rough trails and wondering what they did to make them work, of if they eventually decided no go. The challenge is I need fenders on the roads to the trails, but then the trails tend to beat them up and they quickly become a hazard.

    • I know some riders who run fenders with knobbies, but they are far braver than I am. It seems that if something gets caught between a knob and the trailing edge of the fender, bad things can happen. The Japanese passhunters usually ran tires without knobs, and so do we on our Allroad bikes.

      If I were to design a bike for fenders and knobbies, I’d look to motocross. They have almost a foot of clearance between fender and tire, and the fender isn’t concentric with the tire. When the fender hits the tire as the suspension compresses, it’s at the top, and the trailing edge stays far from the knobs. For bicycles without suspension, you wouldn’t need as much clearance, but the general idea would be a starting point.

  4. jp weigle says:

    I bought my first sets of Honjo’s from Grant Handley back in the 90’s.

  5. Gugie says:

    I’ve been wondering why nobody makes a stay out of tubing. Any mechanical engineer can tell you that most of the strength of a cylinder is from the outer material. Glad to know these are available now!

    • Johan Brox says:

      Strength no, stiffness yes.

      • You are correct, when you look at a tubular stay by itself, it’s less strong than a solid one. However, we are looking at the entire system of how the fender attaches to the bike, and experience has shown that there is no loss in strength or reliability with tubular stays.

    • Gugie says:

      I did a quick calculation. Assuming a round stay of 15 inches long, diameter 0.2 inches (5mm) OD, wall thickness 0.05″ for the tube, aluminum, 1 pound of force at the end, other end constrained in all axes:

      Solid rod:
      Deflection 1.36″
      Bending Stress: 19ksi

      Tube
      Deflection 1.45″
      Bending Stress: 20ksi

      I was guessing on the tube wall thickness from the picture. If I’m correct, the hollow stays are half the weight of the solid ones, but very little change in eiether deflection or bending stress.

      Science.

  6. MattA says:

    Interesting that this should pop up in my feed today! I’ve been trying to source hollow stays for my mudguards (Yes, I’m British) for the last few weeks, but drawing a blank as I can find 4mm OD, or 6mm OD Alu tube but nowhere seemed to stock 5mm OD which is what seems to be needed for VO/Honjo/GB guards. I did try some 4mm with some smaller eyebolts but found it a little flexy and fragile.

  7. Alex says:

    I’m new to all this of course but any neat links on fender installation? I’ve been following the frame builders and looking at the fender installations when they showcase their bikes on Instagram.

  8. Sukho in PDX says:

    This is awesome news, Jan. Compass continues to push the boundaries by developing and sourcing the best of the best. I ride my bike seven days a week as a daily commuter and for fun on the weekends in all weather and terrain. I live in a climate where I appreciate having fenders on all of my bikes, all of the time. Bikes now look weird to me without fenders. Like a lot of folks, I started my Fender Life on cheap plastic ones but quickly found out how inferior they were to a quality set of aluminum fenders. Honjo’s are truly in a class by themselves, and what Compass offers is next level.

  9. Rick Thompson says:

    For Snoqualmie Pass 44 mm tires there was not a Honjo 700c fender wide enough (is there now?), so my Fitz has 52 mm VO Zeppelins. The fenders are actually OK, but i’d like to upgrade the hardware. Would the H50 tubular stays fit these fenders?

  10. marmotte27 says:

    I think it was JP Weigle who prefers to use the Berthoud R clamps for Rinko bikes as rhe don’t mess up the fender stays when they’re repeatedly taken out and tightened again.

  11. Steve says:

    Hi – thanks for the article. Riding with Honjos in the U.K., it is amazing how many comments you receive about them during brevets, so they have not got much recognition here, despite widespread use of plastic mudguards. It becomes slightly tedious to explain that they are not “very heavy”!

    • Yes, I remember that. When we did the first fender test for Bicycle Quarterly, few people believed that Honjo fenders are actually lighter than plastic fenders. The main reason are the stays – flexible plastic fenders have four heavy steel stays, whereas the stiff Honjos need just two lightweight aluminum ones. The other thing is that they last way longer, because you can install them without inbuilt stresses. When I ran plastic fenders, I had the rear fender crack every other year, even though I took the fenders off during the summer months when I did most of my miles.

  12. Frank says:

    On a very small frame with sloping top tube I have found that the rear fender (Berthoud) needed an additional attachment point as well, otherwise it would sway too much. I could could use the rear rack on this bicycle, but if lacking a rack, do you think an additional fender stay could work on the rear as well?

    • There is no reason why you couldn’t use an additional stay on the rear, but it’s usually not needed. You already have three attachment points, which stabilizes the fender in all three dimensions: chainstay bridge, seatstay bridge and fender stay. With the long unsupported arch, just make sure that you use two eyebolts to attach the stay to the fender and that you space them wide enough (but not right at the edge, where the holes aren’t surrounded by enough aluminum to support them). Also make sure you install the fender without inbuilt stresses. Don’t pull it into shape with the stays, but work the fender as described in the instructions until it has the correct radius. That way, the fender should be trouble-free.

  13. davidmtest says:

    How tight should the Berthoud plastic clips be? I’ve had them pop out by themselves, but do they need to be at least slightly loose to do their job?

    • They should be tightened all the way. The stay still will release in most accidents. You certainly don’t want the stay to come loose as you ride – that can cause an accident by itself.

      • Mike says:

        Back when I first started riding year-round, whatever the weather, I had a set of plastic fenders. They came with plastic attachment points for the eyebolts and where the stays attach to the fenders. They were OK at first, and certainly better than nothing on rainy rides, but the plastic become intolerably loose after a year of riding. Rolling over a minor pothole would knock the stays loose. I tried gluing the fender stays, and later zip-tying them, but those were temporary measures. Never again: no more plastic for me. Honjo alu fenders and stays all the way. That said, the new options presented here are intriguing. I particularly like the flat-profile stays. I might order a set for the bike.

  14. thebvo says:

    Here in Japan I’ve seen rinks bikes with fender clamps that are spring loaded. Just pull the D-ring and the slotted fender stay (think Lincoln Logs) can slide out lickety-split. Release it and the clamp springs back into place. Bang! It’s the last missing piece to the Compass brand Rinko setup.

    • The problem with those is that they tend to make noise on rough roads. We may do a feature on how it’s done – it’s a custom installation anyhow.

      • thebvo says:

        Oh boy I’m talking too much!
        As I recall you put a small wooden dowel in the tubular stay to keep it from smushing when tightening the clamp. Does that still apply to these new stays or are they thicker than that Old Stock tubing you used on your Rene Herse?

      • The new stays don’t require the wooden dowel. The old ones may not have required it either – I just liked the finished look, and I was a bit concerned that dirt might get in otherwise, adding weight. (Dirt is much heavier than aluminum!) Realistically, you won’t be able to cram much dirt into the stays, though, so I wouldn’t worry about it.

  15. thebvo says:

    Also still waiting on bigger fender sizes for 700x44mm+ and 26”x50mm+
    Yes I know it’ll hit the chain… unless it’s cut slightly at the chain stay bridge to accommodate this issue. I think Han has fenders on his All-Road bike with the Compass Rat Trap Pass tires.
    🙂

    • Hahn uses our 650B x 62 mm fenders on his bike with Rat Trap Pass tires. They’re a good fit – the outer diameter of a 26″ x 2.3″ tire is the same as a 650B x 42.

      As to 700C x 44 mm, most of those tires go on bikes that can’t accept fenders anyhow. If you want fenders with tires that wide, it’s better to go with 650B wheels, as you’ll run into serious toe overlap issues with bigger wheels.

      • thebvo says:

        A wise person once said…
        https://janheine.wordpress.com/2012/11/06/ride-the-bike-you-have/

        Someday I’ll have my perfect dream bike without (many) compromises, but even then I won’t give up my Rivendell which, like other bikes like it, has room and the braze-ons for all the fenders and racks one could want. But there are other bikes, like you mention that don’t have those. ‘‘Tis also true.

      • davidmtest says:

        True of most bikes, but I run your 700c 44mm tires on my Rivendell with Berthoud 60mm fenders. (Changed to extralight just earlier this week!), not even close to toe overlap.

        Personally I’m hoping your next tire will be a 700c between the 44mm and 55mm sizes, because the 44 has lots of extra room while the 55 would just barely not fit.

      • If there is demand, we could offer our 62 mm-wide in a 700C model, in addition to the 26″, 650B and 650B XL (for 48-42 mm tire) models.

  16. Re plastic m’guards: it’s simple to drill out the rivets on plastic guards and replace the hardware with Berthoud, Honjo, or VO stays etc. The original mounting holes are often useable. If not, drill your own. You can cover any surplus holes by gluing in place the ends of the drilled rivets. With a little thought you can make split guards for easier removal using either a Compass bolt or an ordinary bolt and a wing nut. I’ve done all of these with various brands of guards over quite a few years, using them in Europe, Asia (incl. Japan), and Australia. The results are slightly heavier, but IMO sturdier than aluminium guards. If the guards break (it’s never happened to me) you can reuse the stays. All of that said, I have aluminium guards on my latest bike. I like the beaten metal look.

Comments are closed.