How to Adjust Spring Tension - MAFAC Cantilevers
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How to Adjust Spring Tension - MAFAC Cantilevers
Trying to install a set of MAFAC cantilevers on my '75 Paramount.
Spring tension pushes the pad arm directly on the side of the rim. Obviously, with the pad, pressure on the rim is even tighter. Can't see any way to get pad clearance.
Is there any way to decrease the spring tension in order to get some rim clearance? I don't really want to start bending the spring out of shape however.
If it helps, I'll post a pic but I'm sure everything's installed correctly on the cantilever braze-ons. I saw where some thought there's different front and rear springs. Not the case here.
Thanks
Spring tension pushes the pad arm directly on the side of the rim. Obviously, with the pad, pressure on the rim is even tighter. Can't see any way to get pad clearance.
Is there any way to decrease the spring tension in order to get some rim clearance? I don't really want to start bending the spring out of shape however.
If it helps, I'll post a pic but I'm sure everything's installed correctly on the cantilever braze-ons. I saw where some thought there's different front and rear springs. Not the case here.
Thanks
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First, disconnect the springs on both sides and make sure that one side isn't binding. While you're there, check to make sure both springs are "sprung" away from the brakes at the same angle. They should engage with the brake arms at about the same distance fromt the rim. If they don't, you'll have to bend them a bit to make them equal.
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First, disconnect the springs on both sides and make sure that one side isn't binding. While you're there, check to make sure both springs are "sprung" away from the brakes at the same angle. They should engage with the brake arms at about the same distance fromt the rim. If they don't, you'll have to bend them a bit to make them equal.
The pad arm is tight against the rim without the pad on. With the pad arm on, its really tight. I'm afraid if I press hard on the arms while they are mounted to get some space between the pad and the rim, I'm going to torque the hell out of the spring and perhaps not have the same tension on both sides.
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Youn can bend the spring and debend it several times, won’t hurt anything. They’re made of steel, you’re not going to break them.
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I had to bend one of the springs on my Mafac racers to get it to sit at a distance from the rim. Same problem, only upside-down
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The pad arm is tight against the rim without the pad on. With the pad arm on, its really tight. I'm afraid if I press hard on the arms while they are mounted to get some space between the pad and the rim, I'm going to torque the hell out of the spring and perhaps not have the same tension on both sides.
While there is no difference between springs front to rear, there is a difference side to side. It's worth double-checking to make sure you have the right side's spring in the right spot. Both springs should have the long part coming off the bottom of the coil, then entering into the hole in the brake arm, like so:
Have you got them set up like that?
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It's very easy to mistakenly install the springs on the wrong side such that they are pushing the arms inward instead of outward. Uninstall and switch the springs and you'll find they work just fine.
Edit: @scarlson beat me to it
Edit: @scarlson beat me to it
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But why is the spring pushing the brake arm toward the rim? That doesn't make much sense. It is meant to push the brake arm away from the rim, and then your cable pulls the arm toward the rim. It seems it would have to be pretty badly bent to be pushing the brake arm toward the rim as hard as you are describing.
While there is no difference between springs front to rear, there is a difference side to side. It's worth double-checking to make sure you have the right side's spring in the right spot. Both springs should have the long part coming off the bottom of the coil, then entering into the hole in the brake arm, like so:
Have you got them set up like that?
While there is no difference between springs front to rear, there is a difference side to side. It's worth double-checking to make sure you have the right side's spring in the right spot. Both springs should have the long part coming off the bottom of the coil, then entering into the hole in the brake arm, like so:
Have you got them set up like that?
Last edited by cqlink; 10-20-19 at 04:47 AM.
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It's very easy to mistakenly install the springs on the wrong side such that they are pushing the arms inward instead of outward. Uninstall and switch the springs and you'll find they work just fine.
Edit: @scarlson beat me to it
Edit: @scarlson beat me to it
Thanks for the assist