Hello again
The previous owner sent me a link to the eccentric he installed on the bike: https://funecobikes.com/product/boitier-de-pedalier-excentrique-aluminium-pour-tandem.
The part is made of aluminium and my frame is made of steel. Isn't there a risk of corrosion.
I will try to remove the screws next week and tell you.
Thanks again
Dissimilar metal corrosion can be a problem with steel and aluminum, but the metals have to be in contact for that to be a problem.
For example, aluminum seatposts can bond to steel frames. But if you grease the seatpost, that not only solves that problem, but the grease reduces the amount of water from rain that gets inside the frame as the grease acts as a sealant.
My Nomad Mk II has paint (or powder coat or something like that) on the steel shell around the anodized aluminum eccentric, the anodizing and the paint do a good job of preventing dissimilar metal corrosion.
I do not read French, I do not know if that is anodized or not. But if the shell on the frame has a good layer of paint, it is unlikely that it would be a problem.
My Thorn Sherpa has an aluminum seatpost that I make sure is greased, but most of my other bikes have painted (or some other material) seatposts that prevent the metal to metal contact.
