Is Galvanic corrosion a bigger problem with Generator bikes?
11-28-20, 12:17 PM
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Is Galvanic corrosion a bigger problem with Generator bikes?
I posted this in Electronics - but I figured the long distance crowd might have some experience with this if it is an issue. Just something that popped into my head.
I'm building a traditional Steel Rando bike. It will have an SON SL generator/light system where the current runs through the frame.
Does this worsen Galvanic Corrosion? Are Carbon Seatposts in Steel bikes a really bad idea with Generator Systems?
Thanks
I'm building a traditional Steel Rando bike. It will have an SON SL generator/light system where the current runs through the frame.
Does this worsen Galvanic Corrosion? Are Carbon Seatposts in Steel bikes a really bad idea with Generator Systems?
Thanks
11-28-20, 01:52 PM
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Been riding my generator bike through 20 years of salty winters with no obvious corrosion. They are much more durable than cars in my experience.
11-28-20, 01:56 PM
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Galvanic corrosion doesn't really work that way. And I'm not sure there is going to be any extra potential between the seat post and frame, and their certainly will not be current flowing through the interface.
Are you running the taillight ground through the frame?
Mark the seatpost and take it out once a year, at least. Re-grease/carbon assembly paste and put it back in. Probably wouldn't be a bad idea to run a ball hone through the seat tube. Repeat every year.
Are you running the taillight ground through the frame?
Mark the seatpost and take it out once a year, at least. Re-grease/carbon assembly paste and put it back in. Probably wouldn't be a bad idea to run a ball hone through the seat tube. Repeat every year.
11-28-20, 02:27 PM
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Dissimilar metals immersed in an electrolyte solution generate their own potential between them as long as they are electrically connected which can be as simple as just touching. I don't think running a current through the frame changes the situation. I've had aluminum deteriorate on my carbon bike without a generator, just due to sweat, but carbon and aluminum are much further apart on the galvanic scale than are aluminum and steel. That said, it might be a good idea just to keep an eye on aluminum small parts, just in case. If they're shiny, they're fine. If they go all chalky, they are not fine. I doubt very much that it's a problem or we would have heard about it.
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11-28-20, 02:38 PM
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Thanks - just wanted to make sure as the SON SL system actually uses the bicycle frame as part of the circuit.
11-28-20, 05:09 PM
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Rim dynamos used to have a grub screw on the frame clamp. There was no ground other than the frame, you screwed the grub screw through the paint into the tube. Many Shimano hub dynamo systems use the frame as ground too, the axle is ground. So using the frame as a conductor is nothing new, it's as old as dynamos. Which have been around longer than me.
