Compass UD-1 Rack

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The new Compass UD-1 front rack is a “universal” rack intended for bikes where our other racks don’t fit. It’s an especially good choice for bikes with disc brakes. Like all our racks, it is made by Nitto in Japan to Compass specifications. At 221 g, it’s remarkably light for an adjustable rack, yet it’s strong enough to pass Nitto’s most stringent testing.

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The UD-1 is so simple that you’ll wonder why nobody has made racks like this before. (Actually, a similar rack design was offered by Goëland in the 1950s.) At the top, it attaches to the hole in the fork crown. The U-shaped tube (see top photo) provides maximum stiffness and strength here. The main part of the rack is made from ultra-strong and ultralight Cromoly tubing. It incorporates an attachment for the fender at the front.

The diagonal struts are adjustable at the top, so you can fit this rack on a multitude of bikes. The struts are cut to size after you have figured out how to mount the rack. The struts are made from aluminum, so cutting them is easy. The struts attach to the inside of the tabs, making the rack much more elegant than similar racks where the struts attach to the outside. We enlarged the rack platform slightly to make the shape come together aesthetically. Racks look much better if the rack stays slant outward a bit as they go up from the fork to the platform.

The Compass UD-1 rack fits on many bikes. It’s specifically designed to work with the mid-fork eyelets used by Nitto Campee or Haulin Colin Porteur racks. We offer optional extra-long struts tbat reach the mid-fork low-rider eyelets of production touring bikes like the Surly Long-Haul Trucker.

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We designed the new Compass light mount specifically to fit the UD-1 rack. (The light mount also works on our other racks.) In designing our first adjustable rack, we made sure it has all the functionality and reliability of our other racks.

From the first drawings to the finished racks, the UD-1 took almost two years to design. It’s deceptively simple, but it took a surprising number of prototypes until we got the proportions of the top platform “just right”. And the diagonal stays required several redesigns until they passed the fatigue tests. Few companies fatigue-test their racks, but Compass and Nitto insist on it. We don’t want our customers to be the first to test our new products!

The end result is a rack that fits many bikes, looks great, works well, and will be extremely reliable in the long run. Click here for more information about Compass racks.

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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27 Responses to Compass UD-1 Rack

  1. Guy says:

    does this play nicely with center pull brakes?

    • The arms of centerpull brakes are right in front of the fork crown, so this rack won’t work. We do offer our CP-1 rack, which is designed for our Compass centerpulls. It’s even lighter and stronger than the UD-1, since it isn’t adjustable, but it requires dedicated braze-ons.

      It’s hard to make an adjustable rack to fit a multitude of centerpulls, since the pivot location varies from one brake model to the next.

  2. 47hasbegun says:

    How do these stays differ from Nitto’s existing stays?

    • The stays are the same, only made to custom lengths. We made prototypes with hollow stainless steel stays, but they kept breaking during the fatigue tests. (Stainless is not a good material for racks, because it’s brittle.) Our platforms are made from ultra-strong and lightweight CrMo steel tubing with a chrome-plated finish. If the stays were made from CrMo, you’d have to re-plate them after cutting them to length – not a good option. The aluminum stays are strong enough, light enough, and they don’t break. For an adjustable rack, they are the best compromise.

  3. Agh I bought the nitto original a few weeks ago which annoyingly doesn’t have the fender mount that yours has and the brake bolt mount doesn’t seem as sturdy on the nitto either… Might have to get it modified. I do love the look and feel of Nitto stuff, never disappoints.

    • Nitto’s quality is the best anywhere. It’s fun to work with them, to combine our ideas with their experience, until we have products that we feel deserve the Compass name. The UD-1 racks are different from Nitto’s own models in many large and small details – size and proportions of the platform, attachment to the fork crown, placement of the diagonal stays (inside vs. outside), but also the workmanship of the brazing, polishing and chrome-plating. It’s really the very best Nitto can make.

  4. Jim says:

    Jan
    I have a disc Surly Straggler would I need the extra long struts. I enjoyed your talk last night and It was nice meeting you. Jim

  5. John Thurston says:

    This is a very attractive rack, Jan. It might satisfy a need I have, but I need to study my fork geometry a bit. Can you offer any more measurements?

    Interpolating from the side view, and assuming the deck is 170mm long and the strut is 240mm, I estimated some dimensions:
    A) 33mm vertically from the center of the deck tubing to the face of the hole in the bridge
    B) 37mm mounting stud with 18mm threaded

  6. Bill Lindsay says:

    You are absolutely right that the simplicity and elegance of the design makes you wonder why it doesn’t already exist out there. It’s splendid.

  7. Albert says:

    Hi Jan, is the crown mount threaded rod in a fixed position? Is it designed to pass through the fork crown in it’s entirety or just through the front drilling?

    • It’s fixed – designed for a 73° head angle, but if your head angle is shallower, your rack just points upward a bit, like on many 1940s Alex Singer bikes. The goes all the way through the fork crown, so it’s easy to tighten the nut on the other side.

  8. Lance says:

    Why no mention of the weight limit?

    • The weight limit depends on the length of the stays and how rough your road is. Thanks to its carefully thought-out design, the Compass UD-1 rack is much sturdier than other, similar-looking ones – it’ll be hard to put enough into a handlebar bag to overload it. 5 kg (11 lb.) is no problem. Much more, and your bike’s handling will deteriorate, but for short trips and smooth roads, you can carry more.

  9. Curtis says:

    Any plans to offer a stay that turns in for mounting to cantilever brake posts?

  10. DaveS says:

    The article above mentioned fatigue testing of the UD-1 rack. Is it possible to provide more details?
    Fatigue testing of bicycle parts is an area that I don’t know anything about (google doesn’t seem to find info on this for me) and would be an excellent BQ topic.

    • Most bike parts don’t break from overloading – such as jumping off a huge cliff – but multiple loads that over time form cracks and finally break the part. That is why parts rarely break when they are new, but usually after some use.

      Fatigue testing replicates the loads that occur during hard use, so we can find out whether a part is reliable without riding it for many years. For racks, it involves a machine with a fork that violently pushes up and down. The rack is loaded with a weight, and then the machine is run for a pre-determined number of “cycles”. Usually, the testing loads are greater than those you encounter in normal riding, to speed up the testing.

      Nitto’s testing machines are very impressive. For a photo, check out the article about Nitto’s factory in Bicycle Quarterly 50.

  11. James Derderian says:

    Jan:

    Would it be practical to attach the REAR strut to the platform with sliding/pivot bolts, rather than welding it into its fixed position? This would allow one to position the rack as low as possible. I’m thinking here specifically about 26″ wheeled bikes, on which a rack like this ends up sitting too far above the fender for my liking.
    I can understand that the rack would be less stiff and less stable, but given that my solution in the past has been to cut off the rear strut entirely and attach the rack to the fender for “stiffening”, an adjustable rear strut would actually ADD stability. Just a thought.

  12. James Derderian says:

    Forgive me, my comment is more applicable to the cantilever-post-mount racks. I have not used the UD-1, but I suspect its top-of-tire-to-rack-platform distance would be less objectionable.

    • Unfortunately, when we make racks for non-custom bikes, we don’t control the dimensions of the fork. Especially with unicrown forks, the fork crown hole sits high above the tire… That is why we like our CP1 rack for custom bikes, because its height is determined by the centerpull brake posts, which means it sits perfectly above the tire.

  13. Froste says:

    Can you post a picture of the rack mounted to your Firefly pretty please!?

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