I am responding to a previous question regarding IT band injuries, and the use of Speedplay pedal systems vs all other pedal systems....Yes! Any chiropracter knows that the body is very particular about proper alignment. Pain, muscle and joint strain and even potentially permanent damage can result from prolonged cleat misalignment. There are a couple of pedal systems that I would highly recommend, But first lets touch on a few things regarding why it is so important to choose the correct pedal system, and why it is also neccessary to make sure it is adjusted correctly.
There are many different types of pedals on the market. Not all of them will be Bio-mechanically advantages to triathletes in particular. The more popular systems that will require more adjustments are Look, Time, Ritchey Logic, Wellgo Road and Shimano SPD. These are traditionaly one-sided entry engagment clipless type and have a more tricky entry procedure that will require you to flip and hook the cleat tip mechanism before actually stepping down and engaging the pedal itself. They also require proper cleat alignment and a manual spring adjustment. Because they push your foot back to the manufacturer's idea of your neutral position, pedals like the Time road pedal are a problem if your natural neutral position is not manufacturer's neutral position. Easier said than done. Most folks will require a somewhat longer learning curve process before becoming efficient users. Nontheless, these are much more efficient than NO clipless pedals at all and are much better than the old style 'Cage and Strap' type pedal. Which you can still find on some new bikes as original OEM equipment? Other poor qualities in these types of pedals are a Fixed Cleat Position, Limited Side to Side Float (6-degrees), Poor Cornering Clearance, Heavier Weight and Difficult Engagement & Release. The most important of all the characteristics in these being "Cleat Positioning and Float".
Now, Two great pedal systems come to mind: SpeedPlay and Bebop pedal sytems. Most triathletes for years have found these systems to be clearly more desireable than any other. Both sytems offer between 15 & 19-degrees of side to side variable-float with "NO Fixed-Center" cleat positioning. Free float allows your knees and ankles to decide what position is best. They have dual sided entry w/ built-in internal spring mechanisms that don't require any adjustments-so stepping down without looking and engaging the pedals is made easy. I like the shorter cleat stack height on the Bebops. This is the distance between the bottom of the cleat and your shoe, which makes it considerably easier to run through a transition area w/ your bike in a triathlon. Both systems have the lowest centerline height(11mm), which is the distance between the pedal spindle and the ball of your foot. This feature translates to increased power transmission and less wasted energy between your foot, pedals, cranks and less bottom bracket torgue. Other differences to note are: SpeedPlay cleat will need replacing after about 6 months, depending on how much you may walk around on them (ie: LOOK cleats- 2-3/ year). I would recommend SpeedPlays "Coffee shop Caps" for an additional $ 9.95 to protect the bottom of the cleat for extended wear and life of your cleat. Replacement cleats retail for $ 39.95, Spring rebuild kits are $ 9.95, Speedy Luber Injection Kits $ 24.95. I do like the fact that these are completely rebuildable and have optional cleat mounting kits for a variety of shoe types. However, Bebops cleats contain no plastic and therefor last 4 times as long. The weight differences are minimal. If your looking for the lightest, then Speedplays Titanium X1's are about 150g +(50g or 96g for 4 or 3 hole adapter)cleats=$ 249.00, X2's have a Stainless steel spindle and are 198g +cleats=$ 165.00, X3's have a cromoly spindle and are 225g +cleats. (Note: All models supports 3 & 4 cleat mounting patterns.) Bebop's 8x pedals w/ an "Airomet" Hollow Stainless steel spindle weighing in at 195g +60g for cleats=$ 150.00-170.00, They offer a Cromo spindle model at 205g +60g cleats for $ 100.00-120.00 (Note: Most shoe types, ie: Carnac & SIDI offer optional SPD cleat mounting adaptor's.)
Other upgrades to your shoe system you might want to consider are "SuperFeet" Trim to fit Cycling Orthotic shoe inserts $ 29.95 (No prescription neccesary!) These will offer added fit, support and comfort for increased balance and stability. My Editor's Choice for "BEST UPGRADE" for dollar to performance value$$$. Another custom fit possibility would be "Big Meat" canted wedges to also help custom align your foot, ankle and knee problems. Manufactured by "A Gear Higher", This race proven spacer system can be used equally fitted under both left & right cleats between shoe to help align your foot for the most effective power delivery or built-up more on one side to compensat for any "Bio-Mechanical Leg length differences". Pro's that use the system: World Class-Time Trail Pro-Steve Hegg, Gold Medalist of the N.Y. GoodWill Games-Paul Swift plus many, many more!(Important: You must see your Doctor or Chiropracter before attempting the latter of the two!)
(Technical Note: All pedal sytems should be installed by a trained person. Pedal and or shoe types, use of orthotics, canted shim wedges & spacers and any cleat fore an aft adjustments will require the seat height positioning to change aswell (Seat clamp-height, angle and fore and aft adjustment can also vary.) Which will ultimately effect optimal alignment, balance and positioning on the bike overall.) So don't try to make adjustments to your own cleats unless you are absolutely sure you know what you are doing. Ask a fitting specialist at your local bike shop (Helen's?) for more details (ie: Individual rider size & weight, rider level & experience, training & racing needs, frame types & wheel sizes (650c vs 700c)will further determine proper frame size; aerobar type & size; stem type & size; fork-type, rake & clamp size & crank length and optimum front chainring...[38T & 39T/52/53/54/55/56] and rear cassette ratio's...[11/21, 11/23, 12/23, 12/25, 12/27]).
So that said, I always recommend carefully analyzing your individual needs first and then dicide what upgrade's will best suit you. Keep the rubber side down!