I have one of Cannondales brainstorms on my bike with a four bolt disc rotor bolt pattern. I used an old Magura Clara disc rotor to make a new Avid mechanical disc brake set up work from an older Cannondale hub with the same 4 bolt design.

I would like to know if anyone knows where I can get one of these 4 bolt rotors for a spare either used or new.

I cannot use the 6 bolt rotor that came with the avid brakes obviously but the Magura is working perfectly. The Avid brakes were easy to set up and adjust. They really grab also.

The previous brake setup was CODA Expert disc which I intimately called the Cannondale No Brake system because they were useless. But I learned how to ride downhill fast thanks to these worthless brakes so it has worked out pretty good.

Thanks in advance to anyone who might offer advice.