Use rust inhibitor in aluminum bikes? Yes Dorothy, aluminum corrodes...

Per the periodic table, aluminum is a more reactive metal than iron yet most people are more concerned with corrosion (rust) with steel frames.

Here's a lengthy analysis of an aluminum bicycle frame which failed.  The key takeaway IMHO is that corrosion inside of the bottom bracket area was a major contributor to the failure.  

The key components (again IMHO) for the corrosion were:
1. The bike was used in a humid SALINE environment. 
2. The inside of the tubes were not treated/protected.

Also note there were no signs of corrosion on the exterior of the tubes.

There's also a bunch of manufacturing details which are highlighted as contributing factors to the failure, but I would bet that if the bottom bracket area of the frame had been treated with a rust inhibitor (Frame Saver, LPS-3, Boe Shield, WD-40 or other) then the failure would not have occurred or at least would have taken much longer. 

Here's the link...
https://www.researchgate.net/publication/232410562_Analysis_of_the_cracking_causes_in_an_aluminium_alloy_bike_frame

so do what? spray WD-40 in the water bottle boss holes?

I smiled at the picture of the two polished pucks in the first photograph (aka fig7).  reminds me of making those when doing metallurgical analysis for the welds on the space shuttle.  Lots of polishing to get the metal that shiny.  ;-)

I've witnessed similar corrosion in old aluminum framed mountain bikes but never a failure.  We use this at the shop and both work great for general corrosion protection.  I've coated the inside of the bearing bracket on all of my bikes when I've gotten around to crank work.  A little anal on my part, but the cans are free to use.

Sprayon Outdoor Metal Protectant, #LU777    and    Sprayon Insulating Varnish, #EL601 (used on motor windings)

NoCoGreg wrote:Per the periodic table, aluminum is a more reactive metal than iron yet most people are more concerned with corrosion (rust) with steel frames.

Here's a lengthy analysis of an aluminum bicycle frame which failed.  The key takeaway IMHO is that corrosion inside of the bottom bracket area was a major contributor to the failure.  

The key components (again IMHO) for the corrosion were:
1. The bike was used in a humid SALINE environment. 
2. The inside of the tubes were not treated/protected.

Also note there were no signs of corrosion on the exterior of the tubes.

There's also a bunch of manufacturing details which are highlighted as contributing factors to the failure, but I would bet that if the bottom bracket area of the frame had been treated with a rust inhibitor (Frame Saver, LPS-3, Boe Shield, WD-40 or other) then the failure would not have occurred or at least would have taken much longer. 

Here's the link...
https://www.researchgate.net/publication/232410562_Analysis_of_the_cracking_causes_in_an_aluminium_alloy_bike_frame

NoCoGreg I plan on getting my Tamland stripped down over the winter and get some kind of frame saver put on the inside. I think I would rule out WD-40 of the other three I have heard of frame saver and Boe shield but not LPS-3. Of these 3 is one better than the other two?

Thanks
Zman

Zurichman wrote:

NoCoGreg I plan on getting my Tamland stripped down over the winter and get some kind of frame saver put on the inside. I think I would rule out WD-40 of the other three I have heard of frame saver and Boe shield but not LPS-3. Of these 3 is one better than the other two?

Thanks
Zman

I don't know that there is a significant difference in the various products as I haven't seen any tests. All of these products have followers.  Regarding WD40, there are two products. The WD40 Specialist Rust Inhibitor and the widely used standard "WD40".  Standard WD40 does provide protection against corrosion as it will displace any existing water and dry to a thin tacky finish.  Of the products, Boeshield T9 and Weigles Frame Saver are by far the most widely discussed in the bicycle forums I frequent and you should be able to find one or the other a LBS.

Doesn't aluminum only corrode on the surface?  Whereas iron(steel) keeps corroding through?