What are the main differences between the speedplay x pedals and zero pedals? I know the cleats are different but what is the functional difference and what do people prefer?
Thanks
The zeros have adjustable float (thus the different cleat), and I believe some of the X models vary on q factor (or axle length.) It is pretty much personal pref. Do you want to have a lot of float? Or feel more fixed? Either way you get the benefits of speed play, like less weight, dual sided entry, minimal separation between pedal and shoe.
Plus there is no chance for your shoes to fall off your bike when you run through T1.
homegrown is right. the different q factor is on the ti model which is a bit shorter since it gets some flex when longer.
the zero’s are a slight bit heavier and the cleats cost a bit more.
speedplays are the most popular pedal we sell, you will be happy with them. that first ride seems like you are on a roller-coaster in that it has that bit of side to side shake that I find disconcerting. I am still a Look black cleat guy which explains this 
Not only is float adjustable, but it is independently adjustable for inward and outward float.
I used them for a year, but switched when I found that my cleats failed with no warning. The little c-clip that basically holds the cleat to the pedals split once it fatigued. You could either proactively replace them, or be warned that this could happen at a not so good time. It took less than 1 year for this to happen, but it depends on how much you ride. I ride much more frequently now than during that year where I was only riding a couple of times a week. Aside from this one risk/complaint, they were great pedals.
I don’t know about the shoes never fallling off the bike in transition. Actually after using and loving Speedplay X series for the past three years or so I switched to Shimano Ultegras this year specifically to address the problem of the shoes sometimes falling off. The main problem was when doing a running dismount. Standing with on just one foot as you coast the bike in ready to jump off, it’s a bit disconcerting knowing that just a minor twist will send you to the ground. I’ve seen it happen to a friend with Speedplays and it’s been a close call for myself a couple of times. I’ve also lost a shoe multiple times as I ran the bike back into T2 over bumpy ground.
I still use Speedplays on my road bike, but figure in tris I’m not unclipping much and the Shimanos are much more secure as you can really crank down that release tension.
Funny note on the stack height. In going from Shimano TR01/Nike Poggios with Speedplays to Shimano Ultegras with Sidi T1 Carbon shoes I had to raise the saddle an entire centimeter to make up for the greater stack height! That’s a big increase in a quantity that you usually try to keep to a minimum. I like the Ultegras though, and the Sidis fit great but my transitions suck as I can’t get in them nearly as quickly as the Shimano shoes.
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There’s nothing keeping you from using the Shimano shoes with the Shimano pedals though… right?
nothing technically, but the Shimano TR01s never fit me very well. they were too high volume and on the strap where it goes from fuzzy loop velcro to the hook velcro is about a quarter inch on the wrong side of what would be tight on my foot. Basically I pull the strap to get it tight and it gets stuck at the fuzzy to hook transition and won’t tighten down all the way. My roomate and a couple of other friends have the same problem. I had some neoprene padding taped under the strap to help solve the problem a bit. Compared to the Sidis though the fit seems so sloppy. The Sidi upper just grabs ahold of your foot and feels almost like a road shoe. The upper also always folds under when I try to get in though and causes some major problems. The Shimano problem has been fixed on the TR02 shoes but the overall support of the upper still doesn’t compare to the sidis.
If one is careful to inspect the cleats once a week this is not a problem. You would have replaced it long before it got this bad. The main problem is buying cleats alot if one follows Speedplay’s recommendations. This is true of any pedal system, however, as they have fairly conservative recommendations. Some other systems have handy gauges built into the cleats but that’s kind of difficult with Speedplay’s design.
That’s easy, the Zeros are availible in color.
I was refering to the zeros not coming off in the transition, not the X series. The zeros need tension to release from the pedal. Now if you have a problem with that, I think you need to look at your dismount technique. You shouldn’t be twisting your foot, you should be coming straight off the bike, CX style.
**If one is careful to inspect the cleats once a week this is not a problem. You would have replaced it long before it got this bad. **The main problem is buying cleats alot if one follows Speedplay’s recommendations. This is true of any pedal system, however, as they have fairly conservative recommendations. Some other systems have handy gauges built into the cleats but that’s kind of difficult with Speedplay’s design.
What would I have checked for? The C-clip split due to fatigue. I doubt a hairline crack would have time to form long enough to be caught before the clip just broke like mine did. There was no issue with the plastic body or metal plate, just the clip which is spring steel. Have you seen visible warning signs to this effect?
$40 for cleats is pretty pricy, and based on my current mileage, would potentially need to be done a couple of times a year. That’s $80/year in cleats.
I have put around 17,000km on my current zero cleats without any issues. Aside from the two times I fogot to lube the pedals at the beginning of the week, they have been great.
Everyone is lubing there pedals, right? I only do it once a week (should do it more).
The instructions specify that one should make sure that the c-clips are not developing a flat spot, off the top of my head. Yes, it does get expensive, and appears to be a major source of income for them, but you can buy just the springs by themselves since the entire cleat is pricey. I never defended this aspect of the system.