This may be helpful to people that owns a BH Ultralight RC and thinking about "upgrading" to 25c tires.

I've recently got a set of Easton EA90 SLX wheels with 17.5mm internal width, pair with 25c Michelin Pro4 Endurance v2 tires.

The Ultralight RC frame has enough clearance for this setup. Even the brakes have even clearance to take the wheel on and off with the tires inflated to 95 psi, and with a slight tap to get the tires pass through the brakes.

This may be useful for people that wonder if this setup is going to work.