I didn't invent this experiment; I rode across it by accident.
Most towns and cities have a constant hum of background noise which makes it difficult to distinguish other low-level noises about you. But last Sunday morning I was riding just at dawn and on the busiest road in town at that, a fast stretch out of town, which at this time of the morning was totally empty except for me and my bike.
We've several times here discussed the question of whether a Rohloff gearbox is noisier than a set of derailleurs. My own opinion has always been that the Rohloff makes some noise in all gears but that it is low in the top seven and more irritating because of the psychological impact of its sighing quality in the bottom seven than actually loud. This turns out to be half wrong.
Here's the experiment. Ride out on a Sunday morning around dawn or before. Stop. Wait. Observe the special quality of the ambient silence. Observe that there is still a very low level of background hum.
Find the smoothest road you can. That will normally be a main road. Ride along it at whatever speed you like. Observe the sound your bike makes. Ask yourself what it consists of.
Now, put your Rohloff box in 11th gear (or 14th, any from 8-14 will do) and ride along that stippled yellow line that marks the hard shoulder. Eh, what's this? The sound switches on and off! Check that it's safe, then ride in the middle of the road on the solid white line. Now the sound is gone!
My bike rides on monstrous 622-60mm Big Apple Liteskins at pressures normally under 2 bar. Even on apparently smooth roads they are not silent tyres, though they're not very loud. The white line of smooth paint silenced them altogether.
Whatever sound remains must be the sound of the mechanicals, including the Rohloff. My chainline is straight to within fractions of a millimetre and I use KMC's excellently overbuilt longlife X8 chain with Rohloff's own oil inside a fully enclosing chaincase; the chain is effectively silent. That leave the Rohloff.
I had always assumed that the low noise I heard in the top seven gears was the Rohloff doing its thing. It wasn't. It was the tyres.
The Rohloff in the top seven gears is silent. Period.
My Rohloff, incidentally, hasn't done the thousands of miles that's commonly said to be required to run it in; it's only done just over 3000km.
Andre Jute
