The Chainlink

I have a 1984 Schwinn Voyageur NON SP that I am attempting to convert to 700c. When I say attempt I mean Ive already had the Dyads laced up, frame powdercoated, and pretty much all the components installed (except cantilever brakes) in hopes that it would just work....I ditched the original Dia Compes cantilevers for FSA Engery's (which was probably an ignorant decision) and Im running into issues with the pads not hitting the rim solely.

Instead they hit half the rim and half the tire:
Ive read forum after forum of some lucky people having success with the conversions but they either use the orginial Dia Compe's OR have tried their luck with a couple of other brake sets (Tektro CR720's, Shimano BR-CX50s, Paul Component Touring Cantilevers).

I understand that these conversions on older touring frames are no walk in the park when cantilever brakes are involved. The post mounts on my frame/fork seem closer to the rim compared to modern frames with cantilever bosses. I want to say that my poor choice in brakes is the culprit so I ordered these Shimano BR-CX50s:

http://www.benscycle.net/index.php?main_page=product_info&cPath...

I decided to try these out due to their design and the fact that they come with brake pad spacers. Did I mention my rim width is 24mm... Ultimately these Shimanos might end up failing but I guess thats what I got myself into...

Basically, I need some advice from anyone who has attempted a similar prospect. If you know any older pros in bike shops who have perhaps owned a 80s touring rig OR if you are that pro PLEASE help a youngin' out!

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Sounds like you need 6mm or so closer to the attachment boss.  I'm not sure there's a canti that's going to work.

Measure from the center of the canti mount bolt to the center of the pad holder bolt on the FSA, with the pad adjusted as close as it will go.  I'll check a few different models I have to see if any are shorter. 

Perhaps one of the older type of cantis with the stud-type pads would give you more flexibility.  The bolted-on type sometimes have problems with wider rims even on bikes that haven't been converted to a different rim size.    4mm doesn't seem like a big difference but the slots  the shoes bolt too are often not very long and the angle adjustment in the shoe cup adjusters is only a few degrees at most.

You can still buy replaceable-pad brake shoes for the stud type brakes so once you get them set up you never have to mess with the studs ever again, just swap out new pads when they wear out.    Working bikes has buckets of these old cantis for a couple of bucks.  You could buy a couple and give them a try and see if they work for you without too much monetary investment. 

Paul Components Moto brakes will work. Also VO makes a canti with a lots of adjustability for aplications like this. I've also read that the Tektro CR240 (or whatever) has a nice low profile.

Don't be afraid to extend the slot a few millimeters with a round file. Just don't go overboard.

Extending the slot a mm might help a lot.  American Science Surplus has a needle file kit that isn't too expensive and would be perfect for this.

Also, the two-piece cupped adjustable washers that allow for the brake shoes to be positioned at different angles are often made in two different sizes.   One set is thicker than the other.  Put the thinner set on the rim side of the canti and thicker side on the outside of the arm to give a mm or two more room with thicker rims.  Usually these come assembled the other way around to give the brake shoes a little more depth to reach the rim in the typical situation.  This situation is very atypical since the bosses are a little too high (4mm difference between 27" rim and 700c rim) and also a wider rim that gives even less room here.  Every mm counts! 

Kelvin Mulcky said:

Paul Components Moto brakes will work. Also VO makes a canti with a lots of adjustability for aplications like this. I've also read that the Tektro CR240 (or whatever) has a nice low profile.

Don't be afraid to extend the slot a few millimeters with a round file. Just don't go overboard.
Fmf v-brakes would also work. Or you could hang a long reach side pull from the brake bridge.

Not as elegant if a solution, but it'd get you rolling...

If you've got a set of low-profile cartridge pads, try those on and see if, with the help of some tapered washers, they will get the pads where they need to be.

Eyeballing the location of the canti posts, I am not so sure that Paul's Moto-BMX brakes would work. With typical canti post locations, they are useful for going up in wheel size rather than down - I'm not sure you could get the pads low enough on the posts on those.

Kevin's suggestion of long-reach sidepulls, or Dia-Compe centerpulls, would work.

Something like these should work:

http://www.ebay.com/itm/Shimano-XT-Cantilever-Brakeset-BR-MC70-Deor...

(not my listing, for the record)

I've bought these brakes and Dia Compe 98* (980, 981,982...) (which are also pretty easily adjustable) for between $5-$30. Have swapped between 27" and 700C wheels on a variety of bikes, mostly with the same Sun CR-18 rims that are 22.5 mm wide - and have almost always been able to make it work with a little fiddling around.

If for some reason you absolutely want shiny new brakes you might be out of luck, or have to do a much more clunky work-around. Canti posts on the 80's touring bikes are almost always more closely spaced than modern ones (60-65mm vs 75-80mm) which just compounds the problem when moving to a smaller wheel size - even if you get it to fit, you might end up with brakes that fit but don't work that well, which is not a problem you want to have trying to stop a fully loaded touring bike on a downhill in the rain. Good luck!

Tomas,

I have a set of CR720's that you can try. I'm keeping them, but you're welcome to test-fit them if you want to.

Jesse at Comrade Cycles has plenty of experience brazing new canti posts on old frames built around 27" wheels. It ain't the cheapest, but it's by far the most effective solution. Stop by or call us @773-292-2522.

To extend my response, we at Comrade have tried most all types of brakes to remedy this situation with little permanent solution outside of new cantilever posts on an old frame. There just ain't much room for adjustment while retaining proper leverage/pad connection.

Long reach DP side-pull or vintage centerpulls seems like a better solution to me if all else fails at this point.  Cantis just aint all THAT to begin with IMHO.   Getting out the brazing torch front & rear sounds like more effort than this frame is worth considering a repaint would be in order too. 

Get the canti brakes people recommend and stay away from the caliper brakes.  Properly set up canti brakes blow away a side pull when it comes to stopping power and ones with as long a reach as you need are always going to feel spongy.

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