What is the difference between these 2 pedals? They are both Shimano 105's but 1 set is a bit more expensive while the other one can be found on sale everywhere. I've googled and can't seem to find an answer.

Shimano 105 PD-5700
Shimano 105 SPD-SL

I'm relatively new to cycling and this would be my 1st set of clipless pedals.

Can you provide links?

As far as I'm concerned there's only 1 pair of pedals in the 105 groupset. The PD-5700.
https://cycle.shimano-eu.com/publish/content/global_cycle/en/nl/index/products/road/105_5700/product.-code-PD-5700-L.-type-..html

One is listed by the model number while the other is listed by model name. Aside from that... the price, apparently.

I don't use them but I'm pretty sure that the difference is in the materials that are used to make them (i.e. titanium shaft vs. steel and carbon fiber platform vs aluminum).

You can probably find 5600 series a little cheaper.

There are a bunch of places selling R540 pedals as 105 series.
As long as they aren't the R540s you'll be ok.

Does the SPD-SL model specify whether they are 5600 or 5700? the 5600 is the older model and the one i have. As UK said, SPD-SL is just the pedal style and the 5700 is the model number.

The SPD-SL is the type of cleat.

Got it. Thanks.

I am very new to biking and was going to wait on getting clipless pedals until a friend of mine told me that you burn more calories per hour with them since you are working more muscle groups than you are with standard pedals where you are just pushing down with your front leg. These will work with a Trek 2.1 correct? And will only Shimano shoes work with these?

They'll work with any bike and any shoe that is SPD-SL compatible...which is pretty much any road shoe

Pedals will fit onto any bike. Can be any brand of shoe as long as it has the 3 hole pattern.

this too

The series is 105
The pedal system is SPD-SL
The model numbers inlcude:
PD-5700L or PD-5700S. The letters "S" and "L" denote color (silver or black).
PD-5600, PD-5610S are the older model numbers in the 105 series.
PD-5500 and PD-6600 which was called SPD-R which uses a different cleat system with designators SM-SH90, SM-SH91, SM-SH92. I believe they were in the older 105 and Ultegra series.

The 105 series are made of the same material regardless of letter designation with variations in color.
The "series" name is what differentiates material and weight.

I'm using 5600 105 pedals right now and they work very well. Close to 4k miles on them so far and haven't had a single issue with them.

Thanks to you guys, I was able to get the pedals for $65. I just went to the local shop today and picked up my 1st bike shoes - https://www.performancebike.com/bikes...1592009_400097



Now I just need to learn how to clip and unclip into them.

Good buys! These are great shoes for the price. I have had hot spots with both of my Shimano shoes and the Sidi were too narrow for my feet. I bought the exact pair above after trying them on in the shop. By far the most comfortable yet for me. I am at about 150 miles this week with zero hot spots.

Berlun

Yeah, the guy at the shop said he preferred LG's but not if you have a wide foot. I have a normal foot and these felt more snug and comfy to me than the Shimano shoes I tried on.