Brand-new pedal bearings are almost seized up, should I adjust them or try to "wear them in"?

Question

I bought a pair of brand new XLC PD-C03 pedals and noticed that the factory must have installed the bearing very tightly. While I still can turn the axle by hand, it takes a fair bit of force and I can feel some intense internal crunching.

Now I'm wondering if the factory was just incompetent and I should adjust the bearings, or if this was maybe done intentionally and is meant to take some time to "wear in". Any advice?

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Update: I just loosened the preload to an amount where the pedal, when slightly slapped in the vice, does about 1 full rotation. Thanks to a clever washer between the cone nut and the counter nut that blocked rotation, adjusting was much less annoying than I had expected.

I will mount them on my bicycle now and keep an eye on the bearing play, and if too much play develops too quickly I will give another update here.

Answer 1

Imho, you should adjust the bearing preload. You already found the nut and counter nut under the plastic cap. While you're at it, you might want to check if there's enough grease in the bearings.

Or, since you say they are brand new, you could return them, since those too-tight bearings might mean the bearing races could already be damaged.

Answer 2

Not applicable in your case, but future readers might have pedals which are based on Bushings, not Bearings. Adding for completeness, but your spec page clearly says bearings.

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Cheaper plastic pedals tend to have a shaft through a sintered metal sleeve with oil impregnated, and those can absolutely need bedding-in.

I had a set of these and ended up lightly gripping the threadded end in a drill and spinning it on high for 10 minutes before they loosened up tolerably.

Answer 3

The written description sounds like the bearing’s preload is too tight. That’s as if you took a cup and cone hub and you tightened it too much, or you took a Shimano or SRAM crankset and screwed the preload adjuster in too tightly. If I am correct and you rode a bearing in that state, you’d damage the balls or races.

The problem here is that there’s no obvious way to adjust the bearing preload. If the bearings are cartridge bearings, I am not sure the preload can be adjusted. You could disassemble the pedal to see if there’s any way to loosen the preload, but it may be better to just return the pedals.

In general, bearings do wear in. However, the effect isn't dramatic. The grease gets distributed throughout the bearing and the seals. If you spun the item by hand, you'd probably notice it spins a bit longer after break in. At a microscopic level, all surfaces are rough, and the steel balls and races might also polish themselves a bit smoother as part of that process. This does happen with chains. The difference there might not be perceivable by human eyes. Hence, what you feel is not attributable to a bearing that needs to wear in. For an example of something that breaks in that can be perceived, Campagnolo shifters often feel a bit stiff to start out, then they get smoother as they break in.