Shimano's first entrance into the clipless pedal market was done by licensing the LOOK clipless pedal technology from LOOK, and building a pedal from scratch so that it would enclose the cleat system, look aesthetically pleasing, yet permit the cleat to operate and release correctly. The Shimano LOOK compatible pedals actually use a LOOK retention mechanism housed inside a Shimano body. The LOOK system is an amazingly simple device. The cleat itself has a rounded front nose that slides into the front of the pedal under a lip that is cast as a part of the body in aluminum. At the rear of the cleat is a locking lever that pivots backward under downward pressure. The lever is spring loaded, so once the cleat is pressed down it rotates back, permitting the cleat to seat in the pedal. It then moves forward to it's original position, with the top of the lever gripping the exposed recess, on the back of the cleat. The lever front is shaped like a blunt "V", and has a flat surface with two angled sides that center in the rear of the cleat holding it firmly. The cleat is shaped with inclines at the sides of the rear that slide against matching inclines in the lever, so that small movements in the foot obligate the cleat to center in the pedal again. But when there is a large movement by the cleat, it pushes past where the two inclines slide against each other to the flat front of the lever so the cleat and shoe slide laterally out, and away from the bike. The inclined surfaces on both the cleat and the pedal exaggerate the foot and cleat movement. Again, from a small movement the system will continue to retain the cleat but a sharp or large movement obligates it to go all the way to release the rider's foot. The question of how you individualize the pedal release point remains, because weight and riding style vary by rider. The rear lever pivots on a steel rod that acts as an axle, which is driven through one side of the pedal clamping lever and then into the far side of the pedal. At its base, coiled around the rod on each side, is a flat wound spring with it's ends sticking out. Toward the outer sides of the pedal, one spring end l iesagainst the bottom of the lever's inner shell. This spring end pushes the inside of the lever down pivoting the top of the lever forward, the top of the lever then grips the rear of the cleat from the top. The inner pair of spring ends stick out horizontally, in the center, pointing in the forward direction of the pedal. These two ends are held down by a tiny steel plate that has a threaded bolt passing through the middle. The bolt itself comes up through the bottom of the pedal body and into this interior plate. As the bolt on the bottom of the pedal is turned clockwise from the bottom, it pulls the plate down, increasing the tension on these two spring arms and therefore exerting more pressure to the rear clamping lever, holding your pedal more firmly to make cleat release more difficult. Loosening this bottom screw, would cause the plate to move up, applying less tension on the spring, making release more likely, with less pressure. Shimano makes three pair of LOOK compatible pedals all with slightly different features. They all come with a pair of SM-SH24 cleats and the necessary mounting hardware. With the Black cleats come soft plastic inserts into the cleat that give the hard plastic cleat traction for walking. These anti- skid points are Grey and helpful for those riders that take breaks while on a ride. The Shimano implementation of the LOOK mechanism is physically smaller than the version LOOK itself uses.
The 7401 pedals were the first use of the LOOK license. They have been used by Road riders desiring the best for many seasons now. From the outset, the Dura-Ace 7401 pedal design was recognized as innovative, because Shimano stripped all the excess metal away in the body's shape leaving a light aerodynamic shape that has now been copied. The pedal's spindle length was reduced considerably as they narrowed the body width. The shorter spindle reduced the amount of steel necessary to support the pedal. The body of the 7401 is made of cast aluminum, with a cavity for the LOOK mechanism to penetrate from the back, and has a removable plate to clean and lubricate the mechanism. The body's shape permits the bike to lean up to 34 degrees from vertical without pedal to ground contact, or it is said to have a "34 degree lean angle". The interior of the body is tapped with threads for the spindle to seat. The spindle is made of machined nickel Cro-moly steel that is chrome plated, then has the bearing surfaces ground to a fine smooth finish.
The spindle rests on three sets of bearings. At the outer end are eight 3mm steel ball bearings that rotate, supporting the end of the spindle in a pressed-in steel cup. A bearing with eight roller bearings supports the spindle in the middle. At the inner spindle end are fourteen of the same 3mm ball bearings which rotate in the steel cup/lock nut that threads into the body holding the spindle and bearing assembly in place. This inner end bearing cup, has a second set of threads on the outside for a dust seal and a lockring, which cinch against the body holding the cup positively in place. The lockring is chrome plated with eight rounded facets that require a special tool to adjust. This TL-PD30 tool is made of steel and also has a 15mm open end wrench for tightening the pedal into the arm. The TL-PD30 is included with the pedal set. To open and clean or lubricate the retention system you will need a T-10 Torx wrench which is not included. This bearing system is well conceived and permits tiny, yet permanent adjustments of the internal bearing tension. The adjustment screw for spring release tension is located on the bottom of the pedal and is adjusted with a 4mm allen wrench. The 7401 body is painted in a Silver color with the cast aluminum rear locking lever in anthracite Grey. The pedals weigh 417 grams per pair, without cleats. The cleat set weighs 93 g with the necessary mounting hardware for use on any shoe intended for cleat use. $ Price in Catalog
The 6402 pedal set was introduced for the 1992 cycling season, and is Shimano's most recent incarnation of the LOOK compatible series of pedals. They use styling similar to the 7401 pedals, with one added feature and a less dynamic bearing assembly. The body of the 6402 is made of cast aluminum with a cavity for the LOOK retention system. The 6402 pedal is cast to permit the bike to lean 34¡ before there is pedal to ground contact. The interior of the body is tapped with threads for the spindle/bearing cartridge to thread in.
The spindle system is very much the same as the one used in both the M525 pedals and the 1056 pedals, this, however, has a chrome plated spindle. The spindle is covered, at the thread end, with a plastic sleeve that threads into the body. This plastic material makes it less likely to oxidize or "seize" inside the pedal body. At the end of the plastic sleeve is the inner steel bearing race with twelve 2.2mm steel ball bearings. The bearing cup for the balls is in the form of a steel tube with a bearing cup fashioned at each end. The outer end of this tube then creates the outer bearing cup. It has twelve 2.2mm steel ball bearings between it and a thread onto- the-spindle, steel cone race held in place by another steel nut. The steel tube itself is what the pedal body revolves on and the bearing tension is adjustable. The assembly is tightened or removed using a Shimano TL-PD40 tool that is included with each pedal set. At the bottom of the body is the adjustment screw for the spring release tension. It's adjusted with a 4mm allen wrench not included with the pedals. The unique feature this of pedal set is what Shimano calls "Dual Function" or "Multiple Mode", Shimano's reply to a feature that Time pedals have had for some while. With the Multimode setting in the Fixed position, your cleats are held firmly with lateral movement applying pressure on the release mechanism. In the "Self-aligning Mode", put simply, your foot can, while in the cleat, rotate up to 4 degrees laterally in either direction, without in anyway exerting pressure on the rear locking lever or it's spring. Shimano achieves this by giving the upper piece of the rear lever, that contacts the cleat, deliberate, lateral freedom. In the Fixed mode a centering cam revolves up and applies pressure against this movable piece, preventing any movement. This mode setting is at the rear of the pedal. To open and clean or lubricate the retention system you will need a T-10 Torx wrench that is not included. The adjustment screw for spring release tension is located on the bottom of the pedal and is adjusted with a 4mm allen wrench. The 6402 body is painted in a Grey color with the cast aluminum rear locking lever in Black. The pedals weigh 451 grams per pair, without cleats. The cleat set with the necessary mounting hardware for use on any shoe, intended for cleat use weighs 93 grams. $ Price in Catalog
This is Shimano's most affordable set of LOOK compatible clipless pedals. They share some things in common with the other sets but have something special of their own. The body is made of cast aluminum alloy with a cavity for the LOOK mechanism to be installed at the rear. The pedals' bodys are cast with a 34 degree outside lean, so the bike can be tipped at 34¡ from vertical without pedal to ground contact. The interior of the body is threaded for the spindle and bearing cartridge assembly.
The spindle is a Black steel version of the one used in the 6402 pedals and is the same assembly used in the M525 pedals. The plastic sleeve, bearing races, ball bearings, and bearing tube are the same ones used in the 6402 pedals with the body revolving on the rotating bearing tube. It is again inserted and removed using the TL- PD40 tool which is included. The unique feature of this pedal set is it's Multiple Release mode. At the rear of the pedal is an adjuster that permits either a single release mode, allowing your foot to release only laterally with outward lateral pressure, or a multiple release mode which permits your foot to release laterally (with lateral pressure), vertically with vertical pressure or diagonally outward if you pull your foot in that direction. The multiple release mode is achieved by using rear locking lever made in two pieces that are joined horizontally by a steel pin driven through them. In the multiple release mode, the upper section is allowed to pivot in place with some independence from the lower section, which still pivots, with the tension adjusting spring controlling both of them. This is how it's can release vertically or diagonally. The mode adjuster is at the rear of the pedal and uses a flat blade screwdriver to revolve a plate internally upward, which stops the upper pivot in the single release mode. To open and clean or lubricate the retention system you will need a T-10 Torx wrench which is not included. The adjustment screw for spring release tension is located on the bottom of the pedal and is adjusted with a flat bladed screwdriver. The 1056 body is painted in a pearl Silver color with the cast aluminum rear locking lever in Silver and a Grey upper pivot. The pedals weigh 455 grams per pair, without cleats. The cleat set with the necessary mounting hardware for use on any shoe, intended for cleat use, weighs 93 grams. $ Price in Catalog
