High speed instability
I have a Carbon Trek Domane (isospeed front and rear), purchased new, with about 8k miles. All those miles were on the stock alloy rear wheel plus front alloy rim with SP dynohub. I recently had new wheels built with carbon rims. Front with a brand new SP dynohub, rear with a White Industries hub from an unused wheel. Prior to the wheel upgrade the bike was rock solid descending at speed. On its inaugural ride with new wheels, I had a few descents at speed and it was terrifying. Above 30mph, it would start wandering. Not a shimmy, but just inexplicably jumping left and right. At 40 mph it felt like the bike would move a foot either direction. I'm running the same 32mm Hutchinson tires before and after. Alloy rim depth was 22mm vs 38mm carbon, which should be nothing. I checked for play in the hubs, and they feel solid. I checked the headset and it also feels fine. I'll take the question to my wheel guy, but at the moment I can't understand what it could be.
Any thoughts?
