Brake upgrade question



Smelter

New Member
Jan 9, 2008
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I have recently upgraded my gears with Shimano Sora STI levers, but I'm now looking to replace my ageing Weimman centre pulls to Alloy dual pivot such as the Shimano Sora 3300.
All the brake callipers I can find on their web site have a "reach" of 49mm.
If this is the distance from the bracket shoe axis, to the line of the central bolt, that fixes it to the frame, then is too short for my frame which measures 60mm.
Does anyone know if there are dual pivot brake callipers that will fit?
 
Smelter said:
I have recently upgraded my gears with Shimano Sora STI levers, but I'm now looking to replace my ageing Weimman centre pulls to Alloy dual pivot such as the Shimano Sora 3300.
All the brake callipers I can find on their web site have a "reach" of 49mm.
If this is the distance from the bracket shoe axis, to the line of the central bolt, that fixes it to the frame, then is too short for my frame which measures 60mm.
Does anyone know if there are dual pivot brake callipers that will fit?
Tektro R556 Long Reach Road Calipers Silver 55-73mm
 
Smelter said:
I have recently upgraded my gears with Shimano Sora STI levers, but I'm now looking to replace my ageing Weimman centre pulls to Alloy dual pivot such as the Shimano Sora 3300.
All the brake callipers I can find on their web site have a "reach" of 49mm.
If this is the distance from the bracket shoe axis, to the line of the central bolt, that fixes it to the frame, then is too short for my frame which measures 60mm.
Does anyone know if there are dual pivot brake callipers that will fit?
FWIW. The TEKTRO 521A might work for you, too, even though I think the maximum reach is 59mm (NB: Harris Cyclery specs it at 47mm-57mm) ... lengthening the slot by 1mm should not affect the integrity of the caliper.

Shimano makes a "long" reach, dual-pivot caliper, too -- about 2x the cost of a pair of TEKTRO 521A calipers -- and, I think the max reach is spec'd at 59mm.

Regardless, if you do get a set of dual-pivot calipers, you will need to ENLARGE the back-side of the fork's brake mounting hole & the mounting hole on the rear brake bridge to accept the recessed nut ... it is not difficult to do on the fork, but you may find it to be a little more tedious to do on the rear brake bridge because of the relatively tight space.

So, while there is SOME convenience in setting up either dual-pivot or single-pivot calipers which makes them slightly nicer to work with than centre-pull calipers, the only real reason to change your centre-pull calipers is for cosmetic reasons, IMO ...

Having said that, I will admit to having swapped out the centre-pull calipers on my old Raleigh to single-pivot calipers -- specifically, a 49mm-59mm Shimano 600 caliper in the front & a ~50mm-63mm 90s vintage, Star Chen (?) caliper in the rear ... the latter has a just-long-enough-reach for the 27" wheels. The change was mostly for "cosmetic" reasons ... AND/BUT, only because I already had them!

BTW. Dual-pivot calipers are really JUST a very clever (pure genius, really) variation on center-pull calipers, IMO (others may disagree); so, you won't be gaining any mechanical efficiency by updating your current centre-pull calipers to dual-pivot calipers.

For the time being, you MAY want to scuff any glaze off the braking surface of your current brake pads AND/OR buy new pads ...
 
Smelter said:
I have recently upgraded my gears with Shimano Sora STI levers, but I'm now looking to replace my ageing Weimman centre pulls to Alloy dual pivot such as the Shimano Sora 3300.
All the brake callipers I can find on their web site have a "reach" of 49mm.
If this is the distance from the bracket shoe axis, to the line of the central bolt, that fixes it to the frame, then is too short for my frame which measures 60mm.
Does anyone know if there are dual pivot brake callipers that will fit?

center of bolt to center of rim is the 'reach'. The Tektros that Dave mentions or shimano r600 if the reach is less than 57mm. BUT the bolts won't be long enough for your non recessed frame. You can drill out the place that the brake nut goes for the recessed nut, easy on the front, a challenge for the rear or get 2 front brakes, drill out the front and use the front on the rear w/o a recessed nut..remember to reverse the blocks tho!!
 
Alfeng,
The Shimano "long" reach ones I can find are the R600 & A550, both with a reach of 57mm requiring some 3mm of lengthening!
I can assure you my needs are not cosmetic but purely mechanical.
I currently have three stages of braking :-
1) Move the blocks to the rim.
2) Take up the lack in the pivots of which there are 3 in each "arm" from the cable saddle to the blocks.
3) apply friction!
By the time I've got to stage 3 the levers have moved through quite an angle and I really am not sure what my braking distance is!
New pads was my first move and the softer compound rubber has improved things.

Peter,
Drilling the frame out would be my last resort!
I have been reading up about "Drop bolts" http://sheldonbrown.com/home-drop.html and "Recessed Calliper nuts" http://sheldonbrown.com/harris/brake-calipers.html (2/3rds down the page)

Dave,
The Tektro R556 are the only ones that have the range to fit my frame.
The only details I can find on the web is that "They use modern recessed mounting holes".
One guy advocates buying "a cheap pair of Tektro 800 brakes that are designed for nutted mounting, and swap out the center pivot bolt into a Tektro R556/Riv Silver brake that's normally recessed mount, converting the R556 to nutted instead of allen"

Thanks for the replies.
 
Smelter said:
Alfeng,
The Shimano "long" reach ones I can find are the R600 & A550, both with a reach of 57mm requiring some 3mm of lengthening!
I can assure you my needs are not cosmetic but purely mechanical.
I currently have three stages of braking :-
1) Move the blocks to the rim.
2) Take up the lack in the pivots of which there are 3 in each "arm" from the cable saddle to the blocks.
3) apply friction!
By the time I've got to stage 3 the levers have moved through quite an angle and I really am not sure what my braking distance is!
New pads was my first move and the softer compound rubber has improved things.

Peter,
Drilling the frame out would be my last resort!
I have been reading up about "Drop bolts" http://sheldonbrown.com/home-drop.html and "Recessed Calliper nuts" http://sheldonbrown.com/harris/brake-calipers.html (2/3rds down the page)

Dave,
The Tektro R556 are the only ones that have the range to fit my frame.
The only details I can find on the web is that "They use modern recessed mounting holes".
One guy advocates buying "a cheap pair of Tektro 800 brakes that are designed for nutted mounting, and swap out the center pivot bolt into a Tektro R556/Riv Silver brake that's normally recessed mount, converting the R556 to nutted instead of allen"

Thanks for the replies.
Peter knows what he is talking about and if you went to his shop he could set you up with what you need. Careful and precise drilling in the correct places makes the solution work.
The only other shop I know is Yellow Jersey in Madison, WI that would set you up with what you need. 608.257.4737 is their phone. They would likely tell you the same thing as Peter did, but you can call them and find out. I would ask for Andrew Muzi there. Andrew's shop has done this so many times that they have their own OEM solution.

It really sounds like your old brakes are worn out and need a replacement to be safe.
 
Smelter said:
Alfeng,
The Shimano "long" reach ones I can find are the R600 & A550, both with a reach of 57mm requiring some 3mm of lengthening!
I can assure you my needs are not cosmetic but purely mechanical.
I currently have three stages of braking :-
1) Move the blocks to the rim.
2) Take up the lack in the pivots of which there are 3 in each "arm" from the cable saddle to the blocks.
3) apply friction!
By the time I've got to stage 3 the levers have moved through quite an angle and I really am not sure what my braking distance is!
New pads was my first move and the softer compound rubber has improved things.
Okay ... other than the brake pads, your Weinmann calipers should actually last forever ...

And, some simple (and, I mean SIMPLE) maintenance is probably all they need ...

You need some common HOUSEHOLD OIL (e.g., 3-in-1) ... oil the pivots. Let the brakes "rest" for a-few-hours-to-a-day AFTER oiling & squeezing the brake levers a few times ... repeat a day or two later. AND, repeat, again every 24 hours until the calipers move more freely. If you are ambitious or in a hurry, you can disassemble the calipers, clean them (i.e., polish the pivot shafts with an SOS/Brillo pad), grease them (grease is better than oil), and reassemble.

Now, it should be noted that the OLDER calipers, regardless of brand, had stiffer springs ... but, I only really notice it when I am closing the calipers by hand rather than with the cable & brake lever ...

You want to SHORTEN THE CONNECTING YOKE CABLE. Adjust the connecting yoke cable, when the brakes & levers are "open" whereby the yoke is about half the distance of whatever it currently is above the caliper arms -- yes, that's an arbitrary differential -- making the yoke's angle shallower will mean that the brake calipers will "respond better" than they currently do as they are currently adjusted ...

Now, I didn't realize that MOST people don't know how to adjust their brake cables regardless of whether or not they are centre pull, v-brake, cantilever, single pivot, or double-pivot ... same for cam-action calipers, of course ... until I was helping someone with his bike a few years ago and he asked me if I needed a THIRD-HAND tool ...

Just in case you are one of those people, with your centre-pull calipers (okay, a THIRD-HAND might make things a little easier with centre-pull brakes, but it isn't necessary), you can adjust the yoke's length when the caliper is NOT under tension. You don't need a "third hand" to do this ... just slip the cable off the YOKE CABLE off the metal yoke that is attached to the brake cable by squeezing the calipers with one hand to detension the yoke cable ... now, simply slip the un-anchored end out of the calilper arm ... loosen the anchor bolt on the other caliper arm ... shorten the effective length of the yoke cable by about 1/4" (to start) & re-anchor. Slip the dongle-end of the yoke cable back into its nesting notch on the "other" caliper arm. Slip the YOKE onto the yoke cable. Test your brake lever's pull ...

If it's too tight, then adjust the yoke cable's length accordingly.

If it's still too loose, adjust by a couple of more millimeters.

If your cable hangers don't have adjusting screws, then adjust accordingly by repeating the steps.

FWIW. I like to adjust the distance of the pads from the rim's brake surface so that it is probably about 2+ mm away from the rim ... I know some people who set them much closer.

BTW. The reach on the FRONT is usually several millimeters shorter than the rear ... so, while the reach on your rear may be 60mm, the front may be 57mm ... or, the reach on your front may be 60mm, and your rear may be 63mm.

ALSO. You want to lube the actual brake cable housing ... the ONLY cables & housing that probably don't benefit from a little lube are the "current" Campagnolo cables & housing ... put a dab of grease ("Vaseline" will be fine) between the tip of your thumb & index/middle finger & run the brake cable through the grease. While you just want a VERY THIN LAYER, feel free to add more grease to your fingers, if necessary. Lubing the derailleur cables is a good idea, too.