Cutting/Shortening Seatmast on Speedvagen

[Cloudofheaven]

I appreciate the feedback and advice from everyone. I’m deciding to hold onto the bike until Speedvagen responds back, hopefully within this year. Luckily, I have other bikes in the stable to ride in the meantime.

I will post Speedvagen’s response once I receive it in case there is anyone out there who is in the same situation as I am.

[bahyow]

Whether you use a shim or not, is going to be up to you, your mechanic, and Speedvagen.

However, my advice would not to use aluminum (soda can) if possible. Aluminum and carbon galvanically interact and at the very least need a barrier ply of fiberglass to keep everything copacetic.

The aluminum and carbon create an electric potential (think battery) with an electrolyte. That electrolyte can just be inpure water, salty sweat, or ion infused sports drinks. The aluminum just gets corrosively eaten away.

I had a Specialized Allez Epic back in the day that had an aluminum lug to carbon tube fail. Was apparently quite common, before the bike industry changed manufacturing techniques.

Stainless, titanium, or simple fiberglass all would be better options from a galvanic corrosion perspective.