I have a brand new Seven ID8 with full Campy Record. I'm using the 2007 Campagnolo Record Ultra Torque Compact Carbon Crankset 50/34. I have about 700 miles on the bike since I got it in the Spring. This week I started to notice a suptle "gyroscopic" type feel which has gotten a little worse with each ride. I spent my entire ride today trying to trouble shoot the cause. I cannot feel when I'm coasting at any speed so I think that eliminates the tires, wheels, etc. I've narowed it down to when I'm putting a significant torque on the cranks. Maybe 200+ watts or so I begin feeling a "gyroscopic" whine from the cranks as I turn the pedals. I do not get this when I am just spinning at low watts, only with some significant force on the pedals.

Any idea what could be causing this???? I have a 135 mile event this Wednesday and I'm concerned I could have a mechanical problem. Any input would be greatly appreciated. Thanks!

I begin feeling a "gyroscopic" whine from the cranks as I turn the pedals

I'm guessing you feel a wobble and there's no whine. If that's so, the Hirth joint fixing bolt might be loosening. 10mm hex bit on a torque wrench, 42 Nm/31 ft-lb torque, which is very tight.

The weird thing is it was rock solid for the first 400-500 miles. Then over the past 100 miles or so I started feeling this gyro-scopic feel when putting some significant torque on the crank. It is really not a sound as much as a whinning type vibration from the crankset.

What would cause loosening in such a short period of time?

What would cause loosening in such a short period of time?

Improper installation of the crank, in particular not tightening the fixing bolt enough. Retorque the fixing bolt to specs and see if the vibration disappears. Instructions are on the Campagnolo website.