Originally Posted by evictionsurplus
I have been turning an old Schwinn World Sport into a real machine, maiinly because I am in love with the frame, not the hardware. I just upgraded to some old Shimano 105 brake levers which are fantastic.
I was curious to see if I could use old Shimano Ultegra or 105 brake calpiers on 27" wheels. Everything else on the bike was decent Shimano except for some crappo calipers. Will the new/used (that means cheap ebay) calipers correspond with the wheels? Will I run into issues with brake pad alignment issues with the wheels?
You need to measure the reach as explained at: http://sheldonbrown.com/reach
It is unlikely that any current Shimano calipers will work on this bike.
A caliper brake system consists of 4 parts:
•The brake shoes
All of these parts are upgradable. Many people think first of replacing the calipers, but, in fact, this is the least likely part to make any real difference. A caliper is a simple leverage unit, and there's not all that much to one.
In the case of older bikes, it can be difficult to find a new caliper that will even fit.
The other 3 parts are much more likely to yield real improvement.
Older designs had the cables exit up from the front of the brake levers, arching over the
handlebars. The newer style, where the cable exits out the back of the lever and runs under the handlebar tape is referred to as "aero" because it eliminates the wind drag of the exposed cables.
Aero levers are generally a major improvement over the older type. The pivots are located differently, making it possible to get fairly serious braking from the position where the rider's hand is on top of the lever hood. Traditional levers would permit the use of this position for gentle deceleration only.
Additionally, the better aero levers have better internal cable routing, so there's less cable friction. I particularly recommend the Shimano Tiagra units we sell for $39.95, including cables. See: http://sheldonbrown.com/harris/brakes.html#leversdrop
Older cables used metal-to-metal contact as the inner cable slid through the spiral-wound steel housing. Lubricant was by grease, if the mechanic was conscientious.
Modern cable housings have a Teflon or similar lining. The better inner cables are stainless steel, and are "die drawn" to make them smoother. The result is greatly reduced cable friction, so more of your finger strength is transmitted to the caliper, rather than wasted overcoming cable friction.
•The brake shoes
Modern high-performance brake shoes also make a considerable difference. The very best is the ugly salmon-colored material originated by Scott-Mathauser, and now sold under the Kool Stop name. See: http://sheldonbrown.com/harris/brakeshoes.html
Sheldon "Calipers Last" Brown