Crankbrothers Stamp 7 vs Shimano PD-M520

Buy the Crankbrothers Stamp 7 Small in purple, model 16281, when you want an aluminum platform pedal with 10 adjustable pins per side, for shoe sizes 3 to 10. Buy the Shimano PD-M520, model PDM520L, when you want the black SPD pedal with a chromoly spindle, a sealed cartridge axle, and an open binding. One is a flat pedal. The other is a clip-in. They do not share shoes.

Short version. A helmet still goes on your head. A headlight does not hold your foot. A floor pump fills the tire the pedal is trying to turn. A bottle is the drink, not the interface. Match the pedal to the shoe you already own, or buy the shoe with the pedal.

The Stamp card is model 16281, UPC 641300162816, titled Stamp 7 Small, purple, aluminum platform. The bullets say small pedals are for shoe sizes 3 to 10, or 37 to 43, and a later line says 37 to 43.5. Ten adjustable pins per side. A minimal concave profile. Igus II glide bearings, inboard and outboard, and a double seal. A bullet says a 5-year warranty. The details table says a 12-year manufacturer warranty. Those are not the same promise. Ask which one is on the paperwork in the box, and keep that paper. The material field says aluminum. The highlight repeats Stamp 7, platform, aluminum, purple, small. This is not a Stamp 1, and it is not the large size. If your shoe is an 11, the same bullets point you at the large, not at this model.

The Shimano card is model PDM520L, black, UPC 689228060470. The bullets call it an SPD pedal for enthusiast mountain or road riders, with a compact body, an open binding, mud shedding, adjustable tension, a chromoly spindle, and a sealed bearing cartridge axle. The material field says chromium-molybdenum steel. Dimensions print 4.65 inches long by 4.09 inches wide. Included components says no. Shimano's own model page often ships SM-SH51 cleats with a PD-M520. This Amazon table says the included components are no. Open the box before you tell someone the cleats are there. If they are missing, the cleats are a second purchase, and the shoes still have to be two-bolt SPD shoes. A road three-bolt shoe will not clip into this pedal. The product-style field says flat, which fights the SPD bullets. The bullets and the model name are the pedal. The style cell looks like a bad label.

Crankbrothers model 16281 is the small purple Stamp 7. Shimano model PDM520L is the PD-M520. A large Stamp is a different pedal.

Who should buy the Stamp 7, and who should buy the PD-M520?

Buy the Stamp 7 Small, model 16281, if you ride in the shoes you already walk in, or in flat-pedal shoes, and your size is inside 3 to 10. The platform and the ten pins are the grip. Concave means your foot sits in the pedal instead of on a bar. Pins only work if they meet rubber. A leather dress sole will skate off a pinned pedal the first time the trail points down. Pins also bite shins. That is the trade. The purple small pedal is this card. A large Stamp 7 for sizes 10 to 15 is the other line in the same bullets. Buying the small because it was the color you wanted, then standing a size-12 shoe on a pedal that is too narrow, is how your foot hangs off the outside and the pins catch the middle of the sole.

Buy the PD-M520, model PDM520L, if you already own SPD shoes or you are willing to. The open binding is the mud claim. Adjustable tension is how you make the exit easier while you learn, then tighter when you trust the twist. A chromoly spindle and a sealed cartridge are the durability lines. This pedal does nothing for a sneaker. You will stand on the body, slip, and blame the trail. Cleats are the interface. If this box really includes none, buy SM-SH51 or the multi-release cleat Shimano sells for easier twist-outs, and install them before the ride, not in a parking lot with one tool. Grease the threads. Pedals are left- and right-specific. The left pedal is reverse threaded. Forcing it the wrong way ruins the crank.

Do not buy both and swap them every Saturday unless you enjoy a pedal wrench. Pick the shoe system you will use for the season. A rider who clips in on the climbs and wants a platform for the town errands is looking at a dual-sided pedal, which is neither of these cards. The Stamp is pins on both sides. The M520 is SPD on both sides. There is no flat face hiding on the back of this Shimano.

What the Stamp 7 Small is actually for

Model 16281 is a small aluminum platform in purple, ten adjustable pins per side, Igus II bearings, a double seal, and a shoe-size window the bullets set at 3 to 10 US, with the European line printed as 37 to 43 and also 37 to 43.5. Use the US line if that is how you buy shoes, and try the pedal if you are a 10 and the European numbers disagree with your foot. Pins are adjustable. They ship at a height that may be too sharp for a thin sole or too short for a thick lugged sole. Start lower if you are new. You can raise them when your foot starts to shift. A pin that is a spike against a soft shoe is a hole in the shoe and a bruise on the shin when you miss the pedal.

The warranty cells disagree: 5 years in a bullet, 12 years in the details table. Write down what the insert in the box says. A pedal that creaks in the first month is a bearing or a spindle problem, not a warranty debate. The double seal is there so water and grit stay out of the Igus bushings. It is not a promise you can pressure-wash the pedal from an inch away. Rinse mud off. Do not aim a jet at the seal. The body is aluminum on this card. It will scar when you hit a rock. That scar is cosmetic until a pin hole strips. Replace pins when they bend. Riding on bent pins is how one side grips and the other dumps your foot.

Do: match the small size to the shoe, grease the spindle threads, and tighten to the crank maker's spec. Don't: install the left pedal clockwise. Don't: expect this platform to clip into anything. It will not. Helmet on before you test the pins on a descent. A foot that slips is a shin, and a shin is how people discover they wanted fewer pins or a thicker shoe.

What the PD-M520 is actually for

Model PDM520L is the black SPD pedal with the open binding the bullets credit for mud. Tension is adjustable. The spindle is chromoly. The axle is a sealed cartridge. Dimensions on the card are 4.65 by 4.09 inches. That is a compact body, which is the point: less to hit a rock, less platform under a shoe that is supposed to be clipped, not standing. If you miss the cleat, you are standing on a small body and you will know it. That is why people practice clipping in on grass before they practice it in traffic.

Included components on this table says no. Do not plan the first ride on a cleat that might not be in the carton. SPD shoes have two bolts. The cleat position changes how your knee tracks. Set them, ride a short loop, then move them a couple of millimeters if the knee complains. A cleat that is too far forward or too twisted is a pain you will blame on the pedal. The style cell that says flat is not a second pedal hiding in the listing. The model is PDM520L. The bullets say SPD. Believe the model. The UPC 689228060470 is the reorder check. A silver or a different SPD model is a different box.

Do: set the release tension light while you learn the twist, then raise it if you pull out of the pedal on climbs. Don't: ride SPD shoes on a long walk. The cleat is a marble under your foot. Don't: grease the cleat pocket until the bolt will not hold. A little grease on the threads, thread locker if Shimano asks for it on that bolt, and a torque you can feel without stripping the shoe. Air in the tires matters more than a new pedal if the tire is soft. Fix the tire first.

How to install either pedal so the crank survives

Pedal threads are not the same on both sides. The right pedal, drive side, tightens clockwise. The left pedal tightens counterclockwise. Both stamps usually show the direction. Grease the threads unless the pedal maker says the spindle is already prepared. A dry steel spindle in an aluminum crank is how the pedal seizes and then takes the crank threads with it when you finally remove it. Snug is not a gorilla. A pedal wrench or an 8-millimeter hex, depending on the spindle this pair actually has, beats a pair of pliers on the body.

For the Stamp, check that the pins are even before the first ride. Spin the pedal. A grind means a bearing is dry or a seal is packed with grit from the factory grease migrating. A short spin in the workstand tells you. For the M520, clip in and out twenty times on the stand or on grass. Learn which way your heel twists. Most SPD releases outward. Confirm on these pedals rather than on a memory of a different brand. Adjust tension with the screw the manual points at, a little at a time. A tension set to maximum on day one is how people fall at a stop sign.

Shoes are the other half of the install. Flat shoes for the Stamp can be the cycling shoes with a sticky sole or a skate shoe you accept will get pin holes. SPD shoes for the M520 need the cleat bolts that match the shoe. Tighten them, ride, retighten after the first hour. Cleats settle. A loose cleat is a sloppy release and a lost bolt on the trail. Carry a small hex if those bolts are hex. The multi-tool you already ride with may be enough.

What actually fails on a pedal

Pins fail by bending and by falling out. Replace them in sets so one side is not taller. Bearings fail when a seal is blasted with a pressure washer or when the pedal is ridden loose on the crank and the spindle wobbles. A click once per revolution is often a loose pedal, not a bottom bracket. Check the thread before you replace the crank. Cleats fail by wearing the tips until the pedal will not hold. SPD cleats are a wear item. If you twist and nothing happens, or you twist and you come out when you did not mean to, look at the cleat before you condemn the pedal.

The size fails the Stamp buyer who ignored 3 to 10. A small platform under a large shoe feels nervous because it is. The warranty number fails anyone who lost the insert and then argues 5 versus 12 from memory. Keep the card. The included-components cell fails the Shimano buyer who left the shop without cleats. Look in the box in the parking lot. A road cleat in the bottom of a drawer will not bolt to an SPD shoe.

The other failure is the wrong Stamp or the wrong SPD. Stamp 7 Small, model 16281, purple, is this platform. A Stamp 1 composite pedal is a different body. PD-M520, model PDM520L, is this clip-in. A PD-M540, an EH500 with a platform on one side, or a road SPD-SL pedal is a different mechanism. Read the model on the axle end. If it does not say the model you ordered, it will not match this card's shoe story.

What this comparison is not

It is not a shoe review, a helmet review, or a light review. Helmets and lights are how you stay upright and seen. The pedal is how the foot meets the crank. It is not a power meter. It is not a clipless pedal you can also use in sneakers. The M520 will punish that experiment. It is not a flat pedal you can clip into. The Stamp has pins and no binding.

It is not a reason to change pedals the night before a race or a long ride. Install them, clip or stand, and ride a short loop first. A new cleat position is a knee experiment. Give it a week of easy spinning before you decide the pedal is wrong. Water and air still decide whether the ride is any good. The purple small Stamp and the black M520 are only the interface. Pick the one your shoes can use tomorrow morning.

So which pedal should you buy?

Buy the Crankbrothers Stamp 7 Small, model 16281, when your shoe size is 3 to 10 and you want a purple aluminum platform with ten pins a side. Confirm the warranty paper, because the bullet says 5 years and the table says 12. Buy the Shimano PD-M520, model PDM520L, when you want a black SPD pedal with a chromoly spindle and an open binding, and you will check the box for cleats because this table says included components are no. Grease the threads. The left pedal is reverse threaded. Do not mix a sneaker with the Shimano or a cleat with the Stamp.