Is Nexus 7 supposed to be silent?

Question

I almost bought an e-bike with a belt drive and a Nexus 7 hub today (link to bike). It's my first experience with gear hubs, I've chosen it (over derailleur) for the sake of easy switching in the city and to have a belt drive (less maintenance). An added value for me is the quietness of the belt drive, mentioned in most articles. During the test drive, I noticed that the hub is slightly "ticking" when pedaling. I thought these hubs are quiet, and asked the sales and worksop people in the store. They told me that not only these hubs are not silent, but that it will get louder with time. And that the only silent gear hub is Enviolo.

Ah, also that the bicycle frame acts as a guitar body and amplifies the sound.

Switching gears worked fine.

I wonder:

• How much is it true; should Nexus 7 be making any noise (when pedaling)?
• Is it true that they will get noisier with time?
• Can it be a poorly tuned?
• Can the noise be explained by a faulty hub that I shouldn't accept?

Answer 1

All the Shimano IGH units make noise when pedaling (except in the direct drive gear) and coasting. Nothing you're describing is abnormal. (Your shop does have it right also that if a near-silent IGH was needed, Enviolo is an answer due to the lack of planetary gears inside).

Shimano hubs will tend to be quieter after receiving their regular lubrication service, and then get a little more audible. It's true in that sense that it will probably get louder as time goes on, or at least you wouldn't want to set someone up to expect otherwise. There can be a level of break-in with the gears that may make it sound or feel smoother, but it's not necessarily going to be a major effect.