• Well, the saddle needs to be where the saddle is ... that said, the bike was drawn up with a 100mm stem, right now it's got a 110mm on it because I haven't got a spare 100 ... The saddle would be shifted a tad to account for the diff.

    Shimmy usually starts with the front wheel and then oscillates through the frame. I think the weight and stiffness of the bars and stem combo can have an influence here.

    It wouldn't be the first steel frame that shimmies with hands off, and it's not something you can preemptively design against, really. I wonder whether I could take some vibration out of the system by inserting some foam somewhere? Also I'll double check the front wheel tomorrow to see if it's true and all that.