I trust everything on a racing bike to hold my weight (250) except for 2 components:
Carbon Seatpost
Low Spoke-count Wheels
Now, I'm setting myself up with the seatpost comment, because plenty of big dudes ride on them without issue. I just prefer to have a metal post under my butt.
The low count wheels, however... Trade 'em for something a little bit more substantial. Not that they won't hold you; because most of those sets are very strong, considering the abuse that lighter riders put on them when they stand and hammer. It's just that the continuous stress of a bigger rider on those high tension spokes can lead to quick fatigue of the material, and when one of those spokes goes, the wheel is out of commission until you replace it.
The higher the spoke count, the more forgiving the wheel is if one spoke breaks.
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"I feel like my world was classier before I found cyclocross."
- Mandi M.