What replacement wheels for Scott CR1 or Italian Stallion?

Father Faff

I was changing my brake pads last night and notice the rims on my ancient CR1's Mavic Ksyrium Equipe wheels are looking a tad worn. The wheels have been excellent and have hardly ever needed attention despite my 87kg weight. I am thinking of getting a high end summer bike, perhaps something Italian around £3k, which would likely come with relatively cheap wheels like Ultegra 6800. I was thinking I could put those wheels on the CR1 and get some £1k wheels for the summer bike. So what (strong but light) wheels would you put on the CR1, and what for the Italian stallion?