Creality 3D Printer POM Wheel Plastic Pulley Linear Bearing for Ender 3/Ender 3 ProEnder 3 V2,CR-7,CR-8,CR-10,CR10S,S4,S5 (Pack of 10)

They are not even across the diameter. Leads to the bed wobbling

These were garbage. Poor quality control. Only 3 out of the 10 were usable. The others were out of round. I knew better but tried them anyway and sure enough my print bed had a wavey motion and was impossible to level.

After replacing the wheels on my ender 3 v2, the bed wobbles so i cant even level it properly. 2/3 of the wheels I replaced on the right side arm dont even touch the rail, so all of the weight and pressure is on the bottom wheel. Im quite disappointed with these. Will have to look elsewhere.

these are good bearings took out a lot of noise and wobble in the Z axis.

Before buying these I saw the horrid reviews and was quite concerned about buying these. After looking around the only other options were much more expensive than these. So I played it safe and bought more than what I needed. I bought 20 of these and out of all of them I only had 5 that were unusable. The rest were perfectly fine and had good rolling movement and no side to side play. The 5 that were unusable either had side to side play or had rough / crunchy rolling movement. Just buy more than what you need and do the QC work yourself and you will be good to go.

Some of these may be OK, but after swapping the old wheels on my CR10 bed with these, I noticed a distinct catch in when moving the bed by hand (without the belt connected), and it repeats about every 70mm which is the approximate circumference of these 24mm wheels (where they contact the rails is less than 24mm). I winnowed the batch down to the best and the problem is reduced but it is still present. I have read that can be due to several factors, so I will update this review once I am sure of what the problem is.

Used on a robot arm. Works well

They are exactly what I expected. Havent used them, since they are spares.

Why so many packs of 10? Popular Ender series have 13 Bad reviews - obviously not quality

Several of the rollers have out of round side walls (the part that rides the guide). Doubled checked that the bearings were inserted correctly. The wobbly rollers made it impossible to level my bed. Ended up inspecting and comparing each until I found a straight set to install. 4 of the 10 were not usable. Had a similar issue with an off-brand set but that set had 8 of 10 unusable rollers.