Question 1

What is the difference between SPD, SPD-SL, and Look Keo pedals?

Accepted Answer

SPD is Shimano's two-bolt MTB and commuter clipless system — small recessed cleats that let you walk normally and work in both sides of a double-sided pedal. SPD-SL is Shimano's three-bolt road system, with a larger plastic cleat, wider pedal platform, and single-sided entry for a stiffer power transfer and lower stack height. Look Keo is a direct competitor to SPD-SL and uses a similar three-bolt cleat; Keo and SPD-SL cleats are not interchangeable. In short: SPD for trails, gravel, and commuting; SPD-SL or Keo for road and race.

Question 2

Do all bike pedals use the same thread size?

Accepted Answer

Almost every modern adult bike uses 9/16"-20 TPI pedal threads — the same size across road, MTB, ebike, and most commuter bikes. Older or kids bikes with one-piece cranks (Ashtabula style) use 1/2"-20 threads and a different pedal. The right-hand (drive side) pedal has a normal right-hand thread; the left-hand pedal is always reverse-threaded to prevent it from unscrewing while pedalling.

Question 3

Should I ride flat pedals or clip in?

Accepted Answer

Flat pedals offer instant bail-out and let you reposition your foot — ideal for beginners, technical MTB, commuting in street shoes, and anyone prioritising confidence. Clipless pedals (SPD / SPD-SL / Look / Time) attach your shoe to the pedal via a spring-loaded cleat, giving a more efficient pedal stroke, consistent foot position, and better power transfer. Most road racers, serious triathletes, and XC mountain bikers use clipless; downhill and dirt-jump riders overwhelmingly use flats with grippy shoes.

Question 4

What does "clipless" pedal actually mean?

Accepted Answer

Confusingly, "clipless" refers to the absence of old-school toe clips and straps — the "clips" the pedal no longer needs. Modern clipless systems use a cleat bolted to the shoe that snaps into a sprung mechanism on the pedal. So clipless pedals do clip you in; the name is a historical quirk from the mid-1980s.

Question 5

How much should I spend on my first pair of clipless pedals?

Accepted Answer

Entry-level Shimano SPD (PD-M520, PD-M540, or the PD-EH500 dual-sided model) runs about $45–70 and lasts years. Entry-level Shimano SPD-SL (PD-R540 / R550 / R7000) runs $60–110 and performs very close to flagship Dura-Ace PD-R9100 at a quarter of the price. Don't forget cleats ($15–20) and compatible shoes ($80+). It is almost never worth spending over $200 on pedals until your wheels, tyres, and fit are already dialled.

Question 6

Can I use MTB clipless pedals on a road bike?

Accepted Answer

Yes — plenty of commuter, gravel, and touring cyclists run Shimano SPD or Crankbrothers Eggbeater pedals on a drop-bar bike so they can walk into a coffee shop in normal-looking cycling shoes. You lose some pedal platform area versus SPD-SL or Look Keo, so in a 3-hour-plus effort you'll feel hot spots sooner, but for everyday riding and gravel racing it's a very common and sensible choice.

Bike Pedals Buying Guide — Flat, Clipless & Hybrid

Sizing & fit guidance

What to look for when buying

Top pedals picks

Shimano XT M8100 (SPD)

Crankbrothers Eggbeater 3

Look Keo 2 Max

Race Face Chester

MKS Sylvan Pedal

HT Components ME-03 (Flat)

Time ATAC MX 8 (MTB)

Wahoo Speedplay Aero

Frequently Asked Questions

Keep planning your build

Sizing calculators

Sizing guides by rider

Buying guide

Browse bike size charts

Pedals by rider type

Sizing your bike first?