AMuzi wrote:
On 4/26/2018 4:03 AM, Tanguy Ortolo wrote:
Frank Krygowski, 2018-04-25 17:43+0200:
On 4/25/2018 4:54 AM, Tanguy Ortolo wrote:
One other thing, I have seen suggestions of lubricating only the chain,
and not the sprockets and derailleur. However, I think the derailleur
sprockets still need some lubrication to roll with few friction, do they
not?

No. The friction between the chain's rollers and the sprocket teeth is
negligible. And if you add any lubricant to those surfaces, the
lubricant will soon be filled with abrasive grime. That will accelerate
wear and probably increase the friction.

I was more thinking about the friction between the derailleur sprockets
and their axles, actually.

Indeed those squeak when run dry and the steel ones show
bright red oxide from heat. Yes, do lubricate them, which
for most models means slacking the bolt to get your
lubricant inside.

But Tanguy has so little time! When damaged more than the rest of the
deraileur has aged, just get cheap sealed bearing jockey wheels, fit and
"forget"
https://tacx.com/fr/products/galets-de-derailleurs/