I've got an '07 Orca and am having a horrible front end shimmy problem with it. It happens pretty much any time I go over 35mph. It feels like it's starting around the fork or head tube. I do the "lock your knees on the top tube" trick, and it does help, but I want it to not happen at all. I've done a bunch of research on the archives of RBR , and also read Zinn's stuff on Velo News. I am aware of all the riding form stuff, and have been very careful about that-keeping my hands loose in the drops, weight forward enough (I just had a professional fitting done). I don't think it's road surface or wind related. I've experienced it on really smooth roads and bad ones too, and windy and calm days. I'm becoming convinced it's the bike. On Zinn's Velo News site, he quoted Craig Calfee as saying that the fork can be the culprit if it's not perfectly straight (as in; the dropouts are not aligned perfectly). The other typical equipment suspects such as the front wheel hub and spoke tension, and headset have been checked. Anybody have any advice? I love the bike, but I didn't buy it to keep it under 35mph. This is really stressing me out-any help would be great.