Description
The 6201 DDU shares its dimensions with the more common 6201 ZZ — 12mm bore, 32mm outer diameter, 10mm wide — but swaps the metal shields for rubber contact seals. The DDU seal type keeps more out, which matters for trainers that live in warm, humid pain caves where sweat-spray and dust find their way into every gap.
If your trainer originally came with a 6201 DDU, this is the direct replacement. If you’re upgrading from a 6201 ZZ (the shielded variant) and want better contamination resistance, the dimensions are identical — it’ll drop in without issue. Spec is otherwise the same: chrome steel races, NSK-branded, pre-greased.
Worn bearings of any kind cause the same symptoms — increased noise, vibration through the pedals, and inconsistent power readings. If you’re already in there replacing one, do them all in one go. Use our compatibility checker to see the full list for your model, or get in touch if you’re unsure.
