A Better Way to Adjust Toe-In

compass_washer_installed

Compass centerpull brakes now come with special washers to adjust toe-in. These washers are easy to retrofit on older Compass and even classic Mafac brakes. With this system, you to adjust toe-in only once, when you initially set up the brakes, and then never worry about it again.

toe-in

What is toe-in? It means setting up the brake pads so that the fronts are closer to the rim than the rears. This is important for cantilever brakes, because the fork blades twist when you brake, and the brake pads rotate in relation to the rim. With the right amount of toe-in, the pads will be parallel to the rim when you brake hard.

How much toe-in do you need? There are no firm values because it depends on how much your fork blades twist. It’s trial-and-error. Too much toe-in just makes your brakes work less effectively. Toe-out is worse: Your brakes don’t work well and they howl and squeal. When in doubt, go for a little toe-in rather than too little.

compass_brake_rear

Centerpull brakes attach close to the fork crown, so the fork blades don’t twist significantly. This is why centerpull brakes offer such consistent brake modulation. It’s also the reason they don’t require toe-in. Centerpull brakes work best when the pads are parallel to the rim at all times.

When we introduced the Compass centerpull brakes, the toe-in was not adjustable. In our testing of prototypes, we found that the brakes might squeal for the first few rides, but they became quiet as the pads wore until they were parallel to the rim. Most of our customers have had similar experiences. Riding in the rain helps, because it wears your pads faster.

However, we’ve found since that for a few riders, our brakes squealed, and continued to squeal longer than was acceptable. If the brake pivots on the frame and fork are brazed on at a slight angle, it’s possible that your pads initially have significant toe-out. Rather than wait for the pads to wear away, you’d want to compensate for the misalignment of the post by adjusting the toe-in.

We experimented with numerous ways to adjust toe-in, from the Shimano system of the late 1980s with its wedge-shaped washers to the modern spherical washers. We found all of them hard to adjust, hard to keep adjusted, and they all make changing brake pads a big pain. Basically, you have to hold the adjustment of the brake pad in three directions while you tighten the bolt:

  • angle of pad to rim (seen from the front)
  • alignment of pad to rim (see from the side)
  • toe-in (seen from above)

As you tighten the mounting bolt, all these alignments tend to move. You never get it right, and after a while, you just give up and accept whatever you have as “good enough”. Every Bicycle Quarterly test bike with cantilevers, even those set up by the best pro shops, has had inconsistent brake pad alignment.

What is silly about this process is that, at least on centerpull brakes, the toe-in should be set only once. It compensates for slight misalignment of the brake pivots, and those will remain the same for the life of the bike. Why would you design a system that requires riders to adjust the toe-in again and again, every time they adjust the brake pads? Wouldn’t it be nice if you could adjust the toe-in once, and then it have it remain the same forever? Adjusting and replacing brake pads would be easy!

toe_in_washer

So we adopted a system that does just that. It’s really simple: The washer that goes under the posts of the brake pad has one groove that is deeper than the other. This puts the brake pad at a 2.5° angle, which gives you about 2 mm of toe-in. There is a dot on the reverse (invisible once installed) that shows which groove is deeper. Install the washer in the orientation that you want your toe-in, and you are done. The washer remains in place as you adjust or change the brake pads, so you never have to think about it again. Your toe-in always remains the same.

And setting the adjustment is easy – you just substitute the new washer and then set up the brake as usual. Since the toe-in is pre-selected, you’ll get it right every time. With our post-style pads, tightening the mounting nut only tends to rotate the pads in one direction (alignment of pad to rim), which is easy to compensate. The other movements aren’t affected as you tighten the bolt, which makes it easy to adjust the brake pads. While we offer a special tool to hold the brake pad during this adjustment, it’s not really needed. Usually, I don’t bother with it.

Worried about adjusting your toe-in in smaller increments than 2.5°? As the pads wear, they’ll take care of any small differences. Realistically, if you get within a degree or two of your target value with modern spherical pads, you are doing very well.

Compass_brake_rear_bike

The new washers are included with all Compass centerpull brakes (in addition to the washers without toe-in for bikes with perfectly placed pivots). They also are available as a retrofit for Compass and classic Mafac brakes.

Unfortunately, this method for adjusting toe-in won’t work on most modern brakes, which use “bolt-on” rather than “post-style” pads. For those, somebody should design a system where you adjust the toe-in once and for all, rather than having to fiddle with it every time you adjust the brake pads. (Some cartridge brake pads allow you to replace the pads without disturbing the holders. Unfortunately, this doesn’t help when you have to adjust the pads as they wear, so they still hit the rim in the right place.)

One more piece of news about our brakes: They now are sold individually, to give you a maximum of flexibility when spec’ing your bike.

Click here to learn more about our brakes or to order your set of washers.

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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26 Responses to A Better Way to Adjust Toe-In

  1. Jim says:

    Wow! How incredibly elegant!

  2. Will says:

    Thank goodness for this. My compass center pulls squeal like a stuck pig on my L’Avecaise and have done so ever since I first mounted them two years ago. Your timing is excellent as well as I was just about ready to purchase the super slick GB’s from Japan. While $20 for four washers is completely nuts, I guess it’s a small price to pay for a bit of peace and quiet while out riding in the woods. The only downside is that I’ve gotten use to alerting traffic and pedestrians by tapping on my compass center pulls and there’s nothing quite like that high pitched wail to get people’s attention. I suppose I’ll also invest in an airhorn.

    • We developed the washers for you, and the few others whose brakes continue to squeal. We continuously strive to improve the experience for all our customers. Sometimes, even our rigorous testing doesn’t show issues like this one, so we appreciate the feedback we get from those who use our components.

      Regarding the Grand Bois systems for toe-in adjustment: It was developed by our engineer, but we found it too hard to adjust, so we never put it in production. We shared it with Grand Bois, who put it in production.

      Having seen many maladjusted Grand Bois brakes in Japan, I think it was the right decision to find a better solution…

      • thebvo says:

        I can’t wait to have a bike made for centerpulls. All the advantages you’ve mentioned here and in other posts are super convincing of these being a fantasticly performing brake!

        “We developed the washers mainly for you…” That’s an interesting way to put it. It seems like you developed these groovy washers to improve your product, instead of doing a favor for a few customers. The Compass brakes are beautiful and a top quality product worthy of their price tag and yet, “$20 for 4 washers is completely nuts…”

      • These aren’t just flat washers that are punched out of a sheet of metal. The cost of machining washers in three dimensions is not insignificant. However, if you are handy with a file, you can deepen one groove of the washers you have and save the money. Just make sure you don’t make it too deep, as the eyebolt holding the pad can bottom out, and then the pad will not be held securely.

    • Jimmy says:

      $20 retail for these 4 washers is not nuts. It might be if there were coming from Shimano or something, but at the volume Compass likely can reasonably order and sell, that’s about what I would expect.

      (I sometimes source this sort of hardware for a non-bicycling industry)

  3. Paul Ahart says:

    I’ve just set up Compass brakes on a new L’Avecaise. With polished rims, they squealed horribly. I fixed this with a bit of fine grit sandpaper, which I clamped against the braking surface of the rim with the caliper/pad. A few revolutions of the wheel put a very light bit of abrasion on the rim. First ride after this: like magic! After reading your blog, I’ll check the washer orientation (I noticed the indents) to see if I got them right.
    The washer indents are a brilliant idea. Other bikes on which I installed these brakes had the same squealing problem. I’ll pass this on to my customers.

    • Paul, Interesting idea to make the rim rougher, so the brake pads wear in faster! The washers on the brakes you have are symmetric – no orientation. The new washers with the deeper groove on one side, to get toe-in, are only included with future brake orders – they are brand-new.

  4. Steve says:

    Thanks for the update. Neat! I am just waiting for a frame to be finished and will be installing the brakes – good to know these are available if I need them.

    Off topic but please could you tell me which pump is on the bike in the picture? It looks like a Lezyne road drive, but I thought it lacked a spring, making it difficult to frame mount?

    Thanks

  5. Steve says:

    Thanks – he sounds like a good man to know!

    • Bob C says:

      Mitch is definitely a good man to know. He’s making some of the best bikes in America, is incredibly thoughtful and creative — and he’s a splendid fellow to boot!

  6. nickskaggs says:

    I admire the elegance and simplicity of your solution to this perceived toe in problem.

  7. John Duval says:

    I am curious if you ever tried the TRP pad holders that have a toe-in adjustment built in. These allow the pad to be angled over a wide range relative to the post when it is fully secured to the brake.

    Brand new polished rims do seem to bring out the most horrific squeal. My builder did a fine job lining things up, but salmon pads have never worked for me. May be the dry climate, heavy rider, and that pads take forever to wear down here. Dura-Ace pads have been silent on all my bikes.

    • We tried them. They didn’t keep their adjustment under hard braking, making them worse than no adjustment. Salmon pads seem to be best for riders who roll fast and then brake hard. They aren’t very heat-resistant, so if you prefer to brake for long periods of time to keep your speed in check, black pads (which we also offer) are a better choice.

  8. Alex says:

    Hello Jan, Theo & team, why have you stopped selling the Grand Bois brake adjustment tool?

  9. DavidM says:

    Great to have this post! I’ve been attempting this modification myself already, but probably haven’t filed deeply enough yet. My brake mount post angle leaves the shoes toed out by about 3 degrees. I’m curious about the depth of the deeper groove, and what measurements you would advise?

  10. clacagnoliber says:

    I am afraid my question is a bit off topic but may be of general interest: have the Compass centerpulls or the Mafac Raid enough clearance for the Rat Trap and fenders?
    The Allroad bikes I saw so far are equipped with disk brakes ( the Firefly in the last issue of BQ) or Vbrakes ( the Bontrager).
    I am planning to have an allroad 26″ wheels Rinko touring frame built, I found that the BB7 on my Salsa Fargo brake much better that any cantilever I ever had but as they require a stiffer and less comfortable fork and complicate the Rinko procedure I am not considering them an option.
    PS thumbs up for the last issue of BQ: the articles about Suntour history, the Firefly AllRoad test and Paso de Cortéz tour and the chainline were really interesting.

  11. C Palma says:

    I am so ready for this. My ears thank you for this modification, Jan! My Compass center pulls have not stopped squealing since I installed them last summer. I tried filing the washer to taper the thickness on one side of the washer and create the toe-in. Guess I didn’t thin it enough to create the angle needed.

  12. Almost all our rim brake squealing problems are solvable by installing Velo-Orange Squeal-Free Pads. Jan? Paul?

    • We found that the Velo-Orange pads don’t generate much friction. They don’t squeal, but they don’t brake, either.

      I had them on a test bike and thought they were Kool-Stops, and I couldn’t explain why the Paul brakes on that bike didn’t have any stopping power. It was so scary that mid-ride, I stopped at Free Range Cycles. They recognized the pads, swapped them for Kool-Stops, and braking power was fine thereafter. The brakes squealed, but they also stopped!

  13. Steve Palincsar says:

    There are many cantilever brakes that use Mafac-style smooth post pads. Is there any reason these washers won’t work with them, too?

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